compass
DESCRIPTION
dTRANSCRIPT
COMPASS, Release 2003.5
Training Manual
© 2001, 2002, 2003 by Landmark Graphics Corporation
Part No. 157605 Rev D 2003.5 July 2003
ii COMPASS Training Manual Landmark
© 2001, 2002, 2003 Landmark Graphics Corporation
All Rights Reserved Worldwide
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Landmark Graphics Corporation
Building 1, Suite 200, 2101 CityWest, Houston, Texas 77042, USA
P.O. Box 42806, Houston, Texas 77242, USA
Phone:713-839-2000
Help desk: 713-839-2200
FAX: 713-839-2401
Internet: www.lgc.com
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Note
The information contained in this document is subject to change without notice and should not be construed as a
commitment by Landmark Graphics Corporation. Landmark Graphics Corporation assumes no responsibility for any
error that may appear in this manual. Some states or jurisdictions do not allow disclaimer of expressed or implied
warranties in certain transactions; therefore, this statement may not apply to you.
Landmark COMPASS Training Manual iii
Contacting Support
Landmark operates a number of Technical Assistance Centers (TACs).
Additional support is provided through district support offices around the world.
If problems cannot be resolved at the district level, Landmark’s escalation team
is called to resolve your incidents quickly.
Support information is always available on the Landmark Graphics Support
internet page.
Technical Assistance Centers
North America (Houston, Texas)
713-839-2200 or toll-free 1-877-HELP-LGC
7:30 am - 5:30 pm CST/CDT
Monday - Friday, excluding holidays
Fax: 713-839-2168
Email: [email protected]
South America (Houston, Texas)
713-839-3405
7 am - 5:00 pm Local Time
Monday - Friday, excluding holidays
Fax: 713-839-3646
Email: [email protected]
United Kingdom (Leatherhead)
44-1372-868686
8 am - 5:30 pm Local Time
Monday - Friday, excluding holidays
Fax: 44-1372 868601
Email: [email protected]
Europe and Africa
44-1224-778500
24 hour support including weekends and holidays
**NOTE: 24 hour support is for DIMS only. WellPlan,
Compass, and Profile are supported business hours: 8 a.m. - 6
p.m. Local Time, Monday - Friday, excluding holidays.
Telephone: +44-1224-778500
Email: [email protected]
Middle East and North Africa
9712-676-1745
Fax: 9712-672-5924
Support Mobile Phone: 971-50-551-7273
Email: [email protected]
iv COMPASS Training Manual Landmark
Asia Pacific International
61-8-9481-4488 or
toll-free 1-800-448-488
8:30 am - 5:30 pm Local Time
Monday-Friday, excluding holidays
Toll-Free Numbers:
10-800-6100-253 (China)
001-803-61284 (Indonesia)
00531-61-0021 (Japan)
1800-803-687 (Malaysia)
0800-400-555 (New Zealand)
1800-1611-0207 (Philippines)
00308-61-0046 (South Korea)
0080-61-1350 (Taiwan)
001-800-611-2784 (Thailand)
Email: [email protected]
Bangladesh, Brunei, India, Pakistan, Vietnam
61-8-9481-4488
Email: [email protected]
District Support Offices
Argentina (Buenos Aires)
54-11-4812-5888 or toll free 1-800-800-5263
8:30 am - 5:30 pm Local Time
Monday-Friday, excluding holidays
Fax: 54-11-4812-9777
Email: [email protected]
Australia
1800-448-488
Email: [email protected]
Australia (Melbourne)
61-3-9820-2486
8:30 am - 5:30 pm Local Time
Monday - Friday, excluding holidays
Fax: 61-3-9828-5365
Email: [email protected]
Australia (Perth)
61-8-9481-4488 or toll free 1800-448-488
8:30 am - 5:30 pm Local Time
Monday - Friday, excluding holidays
Fax: 61-8-9481-1580
Email: [email protected]
Brazil (Rio de Janeiro)
55-21-3974-4000 or toll free 000-814-550-3785
8 am - 5 pm Local Time
Monday - Friday, excluding holidays
Email: [email protected]
Chile (LAO TAC, Houston, Texas)
800-201-898
7 am - 5 pm CST/CDT
Monday - Friday, excluding holidays
Fax: 1-713-839-3405
Email: [email protected]
Landmark COMPASS Training Manual v
China
10-800-6100-253
Email: [email protected]
Colombia (Bogota)
571-326-4000 and 571-326-6710
or toll free 1-800-915-4743
8 am - 5 pm Local Time
Monday - Friday, excluding holidays
57-1-326-4000 or 57-1-326-6710
Fax: 57-1-326-6717
Email: [email protected]
Ecuador (Quito)- Halliburton Office
593-2261-844 ext 146
8 am - 5 pm Local Time
Monday - Friday, excluding holidays
Fax: 593-2246-1835
Email: [email protected]
Egypt (Cairo)
20-2-517-3095
(ask for Landmark Technical Support)
9:30 am - 7:30 pm Local Time
Local Business Days, excluding holidays
Fax: 20-2-353-2608
Email: [email protected]
India (New Delhi)
91-11-622-1885
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Local Business Days, excluding holidays
(c/o Samit Enterprises)
Fax: 91-11-647-9246
Indonesia
001-803-61284
Email: [email protected]
Indonesia (Jakarta)
62-21-526-5555 or
toll-free 001-803-61284
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Monday - Friday, excluding holidays
Fax: 62-21-526-6555
Email: [email protected]
Malaysia
1800-803-687
Email: [email protected]
Malaysia (Kuala Lumpur)
60-3-2164-1121 or toll free 1800-803-687
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Monday - Friday, excluding holidays
Fax: 603-2164-1135
Email: [email protected]
Mexico (LAO TAC, Houston, Texas)
52-52083533 and 52-52083868
or toll free 011-888-438-1296
8 am - 6 pm CST/CDT
Monday - Friday, excluding holidays
Fax: 52-55147646
Email: [email protected]
vi COMPASS Training Manual Landmark
New Zealand
0800-400-555
Email: [email protected]
Nigeria (Lagos)
234-1-262-0765
(ask for Landmark Technical Support)
8 am - 5 pm Local Time
Monday - Friday, excluding holidays
Fax: 234-1-262-0769
People's Republic of China (Beijing)
86-10-6465-4501 or toll free 10-800-6100-253
8:30 am - 5:30 pm Local Time
Monday - Friday, excluding holidays
86-10-6465-4502 or 86-10-6465-4503
Email: [email protected]
Peru (Lima)- Halliburton Office
0800-51634
9 am - 6 pm Local Time
Monday - Friday, excluding holidays
Email: [email protected]
Russia (Moscow)
(ask for Landmark Technical Support)
7-095-755-8300
7 am - 5 pm CST/CDT
Local Business Days, excluding holidays
Fax: 7-095-755-8301
Trinidad (LAO TAC, Houston, Texas)
1-888-438-1296
7 am - 5 pm CST/CDT
Monday - Friday, excluding holidays
Fax: 1-713-839-3405
Email: [email protected]
United Arab Emirates (Abu Dhabi)
9712 676 1745
Fax. 9712 672 5924
Email: [email protected]
Support Mobile is 97150 551 72 73
8:30am - 5pm Local Time, Saturday-Wednesday,
excluding holidays
Out of office hours support provided for DIMS only,
call Support mobile number.
United Arab Emirates (Dubai)
+971-4-331-3142
(ask for Landmark Technical Support)
7 am - 5 pm Local Time
Local Business Days, excluding holidays
Fax: 971-4-331-5837
Email: [email protected]
United Kingdom (Aberdeen)
44 (0)1224 778500
8:30am - 5pm Local Time, Monday-Friday, excluding
holidays
Fax. 44 (0)1224 778555
Email: [email protected]
Out of office hours support provided for DIMS only,
call above number and request Oncall Support.
Landmark COMPASS Training Manual vii
Helpful internet links are shown below.
Venezuela (Caracas)
58-212-9530774 or toll free 0-800-526-3627
8 am - 5 pm Local Time
Monday - Friday, excluding holidays
Fax:58-212-9523845
Email: [email protected]
Vietnam (Ho Chi Minh City)
84-8-910-1901
8 am - 5 pm Local Time
Monday - Friday, excluding holidays
Fax: 84-8-910-1902
Name Website Address
Landmark Graphics home page http://www.lgc.com
Landmark Graphics FTP Site ftp://ftp.lgc.com
Oracle home page http://www.oracle.com
FLEXlm license management software
home page
http://www.globetrotter.com/flexlm.htm
Microsoft SQL Server home page http://www.microsoft.com/sql/default.asp
Adobe Acrobat Reader http://www.adobe.com
Microsoft MSDE http://www.microsoft.com/sql/default.asp
viii COMPASS Training Manual Landmark
Landmark COMPASS Training Manual
July 2003 Contents ix
Contents
Contacting Support ............................................................................................................. iii
Introduction ....................................................................................................................... 19
What is COMPASS? .................................................................................................... 19
Modules ................................................................................................................. 21
Who Should Use COMPASS ...................................................................................... 23
Licensing and Installation ............................................................................................ 25
Licensing ................................................................................................................ 26
The Engineer’s Data Model (EDM) Database .................................................. 27
Overview............................................................................................................................. 27
Logging In To the Database................................................................................................ 28
Starting COMPASS ..................................................................................................... 28
Describing the Data Structure............................................................................................. 29
Associated Components ............................................................................................... 31
Associated with Designs: ....................................................................................... 32
Associated with Cases: .......................................................................................... 32
Copying and Pasting Associated Items .................................................................. 33
Rules for Associating Components ........................................................................ 33
Common Data ..................................................................................................................... 35
Data Locking....................................................................................................................... 36
How Locking Works .............................................................................................. 36
Concurrent Use of Same Data By Multiple Users .............................................................. 38
How the Well Explorer Handles Concurrent Users ..................................................... 38
Same User on Same Computer .............................................................................. 39
Multiple Users, Different Computers .................................................................... 39
Reload Notification ...................................................................................................... 39
Simultaneous Activity Monitor (SAM) .............................................................................. 41
Importing and Exporting Data ............................................................................................ 42
Importing Data into the EDM Database ...................................................................... 42
Importing EDM Well Data from Another Database .............................................. 42
Importing a DEX File Into the Database ............................................................... 43
Exporting Data From the EDM Database .................................................................... 44
Exporting Data in XML Format ............................................................................ 44
Exporting Well Data in DEX Format .................................................................... 45
Wellbore Planner Import / Export ............................................................................... 46
Wellbore Planner Import ....................................................................................... 47
Wellbore Planner Export ....................................................................................... 48
DIMS for Windows Survey Import ............................................................................. 48
Well ........................................................................................................................ 48
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x Contents July 2003
Sidetrack ................................................................................................................ 48
Tool Mappings ....................................................................................................... 48
Using Datums in EDM ....................................................................................................... 50
Definition of Terms Associated With Datums ............................................................ 50
Project Properties ................................................................................................... 50
Well Properties ...................................................................................................... 50
Design Properties ................................................................................................... 52
Setting Up Datums for Your Design ............................................................................ 52
Changing the Datum .................................................................................................... 53
Using the Well Explorer .............................................................................................. 57
Overview............................................................................................................................. 57
Introducing the Well Explorer ............................................................................................ 58
Well Explorer Components ......................................................................................... 59
The Tree ................................................................................................................. 59
Associated Data Components ................................................................................ 60
The Recent Bar ............................................................................................................ 60
Displaying/Sizing the Well Explorer and Recent Bar ................................................. 60
Positioning the Well Explorer ...................................................................................... 61
Tracking Data Modifications ....................................................................................... 61
Drag and Drop Rules ................................................................................................... 62
Well Explorer Right-Click Menus ............................................................................... 63
Working at the Database Level .................................................................................... 63
New Company (Database Level) ........................................................................... 64
Instant Plan (Database Level) ................................................................................ 64
Instant Survey (Database Level) ............................................................................ 64
Well Name (Database Level) ................................................................................. 65
Wellbore Name (Database Level) .......................................................................... 65
Lithologies (Database Level) ................................................................................. 66
Import (Database Level) ........................................................................................ 67
Search (Database Level) ........................................................................................ 67
Refresh (Database Level) ....................................................................................... 68
Expand All (Database Level) ................................................................................. 68
Collapse All (Database Level) ............................................................................... 68
Working at the Company Level ................................................................................... 68
Open (Company Level) ......................................................................................... 69
New Project (Company Level) .............................................................................. 69
New Attachment (Company Level) ....................................................................... 69
Paste (Company Level) .......................................................................................... 69
Rename (Company Level) ..................................................................................... 70
Delete (Company Level) ........................................................................................ 70
Export (Company Level) ....................................................................................... 70
Search (Company Level) ....................................................................................... 70
Survey Tools (Company Level) ............................................................................. 70
Properties (Company Level) .................................................................................. 81
Landmark COMPASS Training Manual
July 2003 Contents xi
Using the Company Properties > Wellbore Types Tab ......................................... 88
Expand All (Company Level) ................................................................................ 89
Collapse All (Company Level) .............................................................................. 89
Working at the Project Level ....................................................................................... 89
Open (Project Level) .............................................................................................. 90
New Site (Project Level) ........................................................................................ 90
New Attachment (Project Level) ........................................................................... 90
Copy (Project Level) .............................................................................................. 91
Paste (Project Level) .............................................................................................. 91
Rename (Project Level) ......................................................................................... 91
Delete (Project Level) ............................................................................................ 91
Export (Project Level) ........................................................................................... 91
Search (Project Level) ........................................................................................... 91
Targets (Project Level) .......................................................................................... 91
Lease Lines (Project Level) .................................................................................. 92
Properties (Project Level) ...................................................................................... 92
Expand All (Project Level) .................................................................................... 96
Collapse All (Project Level) .................................................................................. 96
Working at the Site Level ............................................................................................ 96
Open (Site Level) ................................................................................................... 97
New Well (Site Level) ........................................................................................... 98
New Attachment (Site Level) ................................................................................ 98
Copy (Site Level) ................................................................................................... 98
Paste (Site Level) ................................................................................................... 98
Rename (Site Level) .............................................................................................. 98
Delete (Site Level) ................................................................................................. 98
Export (Site Level) ................................................................................................. 99
Search (Site Level) ................................................................................................. 99
Unlock (Site Level) ................................................................................................ 99
Templates (Site Level) ........................................................................................... 99
Properties (Site Level) ........................................................................................... 104
Expand All (Site Level) ......................................................................................... 107
Collapse All (Site Level) ....................................................................................... 107
Working at the Well Level ........................................................................................... 108
Open (Well Level) ................................................................................................. 109
New Wellbore (Well Level) .................................................................................. 109
New Attachment (Well Level) ............................................................................... 110
Copy (Well Level) ................................................................................................. 110
Paste (Well Level) ................................................................................................. 110
Rename (Well Level) ............................................................................................. 110
Delete (Well Level) ............................................................................................... 110
Export (Well Level) ............................................................................................... 110
Search (Well Level) ............................................................................................... 110
Properties (Well Level) .......................................................................................... 111
Expand All (Well Level) ........................................................................................ 115
Collapse All (Well Level) ...................................................................................... 115
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xii Contents July 2003
Working at the Wellbore Level ................................................................................... 115
Open (Wellbore Level) .......................................................................................... 116
New Plan (Wellbore Level) ................................................................................... 116
New Actual Design (Wellbore Level) ................................................................... 116
New Survey (New Wellbore) ................................................................................ 117
New Attachment (Wellbore Level) ........................................................................ 117
Copy (Wellbore Level) .......................................................................................... 117
Paste (Wellbore Level) .......................................................................................... 117
Rename (Wellbore Level) ...................................................................................... 117
Delete (Wellbore Level) ........................................................................................ 117
Export (Wellbore Level) ........................................................................................ 117
Import DIMS Surveys (Wellbore Level) ............................................................... 118
Targets (Wellbore Level) ....................................................................................... 118
Properties (Wellbore Level) ................................................................................... 118
Working at the Design Level ....................................................................................... 120
Open (Design Level) .............................................................................................. 122
Edit (Design Level) ................................................................................................ 123
View (Design Level) .............................................................................................. 123
New Survey (Design Level) .................................................................................. 123
New Attachment (Design Level) ........................................................................... 123
Paste (Design Level) .............................................................................................. 124
Rename (Design Level) ......................................................................................... 124
Delete (Design Level) ............................................................................................ 124
Export (Design Level) ........................................................................................... 124
Import (Design Level) ........................................................................................... 124
Casings (Design Level) .......................................................................................... 124
Formations (Design Level) .................................................................................... 125
Reports (Design Level) .......................................................................................... 126
Properties (Design Level) ...................................................................................... 126
Concepts ............................................................................................................................. 133Overview............................................................................................................................. 133
Accessing Online Documentation ...................................................................................... 134
Using the Main Window..................................................................................................... 135
Using the Well Explorer .............................................................................................. 135
Status Window ....................................................................................................... 136
Viewing Preferences .............................................................................................. 137
Browser Window ................................................................................................... 137
Locked Data Items ................................................................................................. 138
Concurrency Control .............................................................................................. 138
Data Viewer ........................................................................................................... 139
Recent Bar or Recent Selections List .................................................................... 139
Using the Menu Bar ............................................................................................................ 140
Using Toolbars.................................................................................................................... 142
Using Status Bar ................................................................................................................. 143
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July 2003 Contents xiii
Accessing the Online Help ................................................................................................. 144
Finding Information in Help ........................................................................................ 145
Frequently Asked Questions ........................................................................................ 145
Configuring Units ............................................................................................................... 146
Planning Module ............................................................................................................. 149Overview............................................................................................................................. 149
Defining Targets ................................................................................................................ 150
Using Targets ............................................................................................................... 150
Target Geometry .......................................................................................................... 150
Accessing the Target Editor ......................................................................................... 151
Using the Target Editor ................................................................................................ 152
Using the Target List ............................................................................................. 152
Defining the Target Geometry ............................................................................... 153
Defining Drilling Targets ....................................................................................... 158
Using the Target Viewer .............................................................................................. 159
Target Landing Point Adjust ................................................................................. 159
Creating a Plan.................................................................................................................... 160
Naming the Plan and Defining the Depth Reference Point ......................................... 160
Specifying the Tie-On Point ........................................................................................ 160
Defining the Survey Tool Program .............................................................................. 162
Specifying the Vertical Section ................................................................................... 163
Using the Plan Editor .......................................................................................................... 164
Accessing the Plan Editor ............................................................................................ 164
Plan Grid ...................................................................................................................... 166
Selecting the Planning Method .................................................................................... 166
Using the Plan Method Window .................................................................................. 166
Using the Plan Editor Toolbar ..................................................................................... 167
Adding a Plan Section .................................................................................................. 168
Deleting a Plan Section ................................................................................................ 168
Editing the Plan Grid ................................................................................................... 168
To Highlight Plan Sections in Views (plots): ........................................................ 169
Incremental Measured Depths ............................................................................... 169
Viewing the Planned Surveys ...................................................................................... 170
Planning Methods ............................................................................................................... 171
2D Directional Well Planning ...................................................................................... 172
Slant Well Design .................................................................................................. 172
S-Well Design ........................................................................................................ 173
3D Well Planning ......................................................................................................... 176
Build/Turn Curves ................................................................................................. 176
Dogleg/Toolface Curves ........................................................................................ 178
Build-Turn vs. Dogleg-Toolface ............................................................................ 181
Optimum Align ...................................................................................................... 182
Hold Tool ............................................................................................................... 187
Thread Targets ....................................................................................................... 188
COMPASS Training Manual Landmark
xiv Contents July 2003
Nudge ..................................................................................................................... 192
Project Ahead ......................................................................................................... 192
Applied Walk Rates .............................................................................................. 193
Using the Plan Optimiser .................................................................................................... 195
Torque and Drag Calculations ..................................................................................... 196
Load Cases ............................................................................................................. 197
Plan Optimizer Editor .................................................................................................. 198
Using the Optimizer Tabs ...................................................................................... 199
Buttons and other Features .................................................................................... 205
Grid Manipulations ...................................................................................................... 207
Grid Columns ......................................................................................................... 207
Tubular Catalog ..................................................................................................... 208
Plan Optimizer Viewer ................................................................................................ 209
The Graphs ............................................................................................................. 209
Planning and Anti-Collision ............................................................................................... 212
Planning Reports................................................................................................................. 213
Planning Report Options ........................................................................................ 214
Anti-Collision Module................................................................................................... 215Overview............................................................................................................................. 215
Specifying AntiCollision Analysis Parameters................................................................... 216
Error Systems ............................................................................................................... 217
ISCWSA ................................................................................................................ 217
Cone or Error ......................................................................................................... 219
Scan Methods ............................................................................................................... 219
3D Closest Approach ............................................................................................. 220
Traveling Cylinder ................................................................................................. 220
Trav Cylinder North ............................................................................................... 221
Horizontal Plane .................................................................................................... 221
Comparing the Scan Methods ................................................................................ 222
Traveling Cylinder Scan and Near-Perpendicular Intersections ............................ 223
Warning Types ............................................................................................................. 224
Error Ratio ............................................................................................................. 224
Depth Ratio ............................................................................................................ 225
Rules Based ............................................................................................................ 225
Error Surfaces .............................................................................................................. 225
Elliptical Conic ...................................................................................................... 226
Circular Conic ........................................................................................................ 226
Combined Covariance ............................................................................................ 227
Including Casings ........................................................................................................ 228
Selecting Offset Designs for Anticollision Analysis .......................................................... 229
Anti-Collision Offset Designs ..................................................................................... 229
Specifying Anticollision Interpolation Intervals and Other Settings ........................... 231
Analyzing Results ............................................................................................................... 232
Using Live Graphs ....................................................................................................... 232
Landmark COMPASS Training Manual
July 2003 Contents xv
Using the Live Graph Toolbar Buttons .................................................................. 232
Example Anti-Collision Analysis ................................................................................ 235
Spider View ................................................................................................................. 236
Viewing Casing Tunnels ........................................................................................ 237
Ladder View ................................................................................................................ 238
To set up a Ladder Plot: ......................................................................................... 239
Optionally .............................................................................................................. 239
Equivalent Magnetic Distance .............................................................................. 242
Separation Factor View ............................................................................................... 242
Reduced Error Bars with Depth ............................................................................. 243
Traveling Cylinder View ............................................................................................. 244
To set up a Traveling Cylinder Plot ....................................................................... 245
Optionally .............................................................................................................. 245
3D Proximity View ...................................................................................................... 251
To set up a 3D Proximity graph: ............................................................................ 251
Interactive Scroll Bar ............................................................................................. 251
Reports ................................................................................................................................ 254
Ellipse Separation Report ............................................................................................ 254
To set up a data scan report: .................................................................................. 255
Definition of sections: ............................................................................................ 255
Error Ellipse Report ..................................................................................................... 257
To set up an ellipse survey report: ......................................................................... 258
Survey Module ................................................................................................................. 263Overview............................................................................................................................. 263
Defining New Survey Properties ........................................................................................ 264
Naming and Specifying General Information About the Survey ................................ 264
Specifying the Tie-On Point ........................................................................................ 266
Specifying User Defined Tie-On Points ................................................................ 267
Specifying Tie-On Points From Wellhead ............................................................. 267
Specifying Tie-On Points From Survey ................................................................. 267
Validating Survey Data ................................................................................................ 268
Managing Survey Data ....................................................................................................... 269
Using the Survey Editor ............................................................................................... 269
Using the Survey Editor Tool Bar ............................................................................... 271
Interpolating Surveys ............................................................................................. 271
Project Ahead ......................................................................................................... 273
Survey Data Quality ............................................................................................... 280
Input Validation ..................................................................................................... 281
Importing Survey Data ................................................................................................. 282
Survey Types ......................................................................................................... 283
Analyzing Survey Data ....................................................................................................... 285
Using Varying Curvature ............................................................................................. 285
Using the 2D Varying Curvature Graph ................................................................ 286
3D Varying Curvature graph ................................................................................. 287
COMPASS Training Manual Landmark
xvi Contents July 2003
Using Graphs to Analyze Survey Data ........................................................................ 288
Max / Min View ..................................................................................................... 289
Analysis Graphs ..................................................................................................... 289
Plotting Multiple Surveys ...................................................................................... 290
Relative Instrument Performance .......................................................................... 292
Survey Reports.................................................................................................................... 294
Survey Export ..................................................................................................................... 295
Export File Format ................................................................................................. 295
Plots ....................................................................................................................................... 299Overview............................................................................................................................. 299
Comparing Live Graphs and Wall Plots ...................................................................... 299
Live Graphs ............................................................................................................ 299
Wall Plots ............................................................................................................... 300
Using Live Graphs .............................................................................................................. 301
Accessing Live Graphs ................................................................................................ 301
Live Graphs Common to All Modules .................................................................. 301
Live Graphs in the Survey Module ........................................................................ 301
Live Graphs in the Anticollision Module .............................................................. 301
Customizing Live Graphs ............................................................................................ 302
Using the Live Graph Toolbar Icons ..................................................................... 305
Legend Box ............................................................................................................ 306
Using the 3D View ............................................................................................... 306
Using the Vertical Section View .......................................................................... 307
Using the Plan View ............................................................................................. 308
Using the Wall Plot Composer ........................................................................................... 309
What is the Wall Plot Composer? ................................................................................ 309
Accessing the Wall Plot Composer ............................................................................. 309
Examining the Wall Plot Composer Components ....................................................... 310
What is an Object? ................................................................................................. 310
What is a Sub-Object? ........................................................................................... 311
Setting Up the Wall Plot Composer Page .................................................................... 311
Using the Toolbars ....................................................................................................... 312
Using the General Toolbar ..................................................................................... 313
Using the Object Toolbar ....................................................................................... 314
Using the Layout Toolbar ...................................................................................... 316
Working With Wall Plot Composer Objects and Sub-Objects .................................... 318
Adding an Object to the Wall Plot ......................................................................... 318
Adding an Art Object to the Wall Plot .................................................................. 318
Selecting an Object(s) on the Wall Plot ................................................................. 319
Selecting a Sub-Object(s) Within an Object on the Wall Plot ............................... 319
Moving an Object(s) or Sub-Object(s) on the Wall Plot ....................................... 319
Deleting Object(s) or Sub-Object(s) ...................................................................... 320
Resizing an Object(s) or Sub-Objects(s) ............................................................... 320
Placing Object(s) and Sub-Object(s) Relative to Each Other ................................ 321
Landmark COMPASS Training Manual
July 2003 Contents xvii
Aligning Object(s) and Sub-Object(s) on the Page ............................................... 321
Editing Style, Thickness, and Color ...................................................................... 321
Exporting Selected Objects .................................................................................... 321
Designating an Object’s Properties as the Default Setting .................................... 322
Setting an Exact Graph Size .................................................................................. 322
Embedding Images on a Plot ................................................................................. 322
Changing Object Properties ......................................................................................... 322
Changing XY Graph Properties ............................................................................. 323
Changing Traveling Cylinder Graph Options ........................................................ 324
Changing 3D Graph Options ................................................................................. 325
Changing Data Boxes Graph Options .................................................................... 326
Changing Geological Columns Graph Options ..................................................... 326
Changing North Arrow Options ............................................................................ 326
Changing Legend Options ..................................................................................... 327
Changing Text Box Options .................................................................................. 327
Changing Picture Options ...................................................................................... 327
Changing Rectangle, Polygon, or Ellipse Options ................................................ 328
Changing Line, Segmented Line, Curved Line, or Arrow Options ....................... 328
Using Wall Plot Composer Right-Click Menus .......................................................... 328
Wall Plot Composer Files ............................................................................................ 329
Tools ...................................................................................................................................... 331Overview............................................................................................................................. 331
Geodetic Calculator ........................................................................................................... 332
The Calculator .............................................................................................................. 332
Geodetic System, Datum and Map Zone ............................................................... 332
Results .................................................................................................................... 333
Geomagnetic Calculator ..................................................................................................... 334
Using the Site Optimizer..................................................................................................... 337
Site Optimizer .............................................................................................................. 339
Targets ................................................................................................................... 339
Design Constraints ................................................................................................. 339
Site Centre .............................................................................................................. 340
Optimiser Viewer ......................................................................................................... 341
Results .................................................................................................................... 341
Theory ................................................................................................................................... 343Overview............................................................................................................................. 343
Introducing Directional Drilling ......................................................................................... 344
Origins ......................................................................................................................... 344
Early Means of Directional Control ............................................................................. 346
Oriented Drilling .................................................................................................... 346
Survey Measurement ............................................................................................. 347
Modern Directional Drilling ........................................................................................ 348
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xviii Contents July 2003
Mud Motor ................................................................................................................... 350
Measurement Systems ................................................................................................. 352
Measurement While Drilling ....................................................................................... 353
Emerging Technologies ............................................................................................... 356
Coiled Tubing/Underbalanced Drilling ................................................................. 356
Multi-Laterals ........................................................................................................ 357
Rotary Steerable Systems ...................................................................................... 359
Geo-Steering ................................................................................................................ 361
Survey Calculation Methods............................................................................................... 364
Calculation Methods .............................................................................................. 366
Geodesy .............................................................................................................................. 368
System .......................................................................................................................... 368
Datum ........................................................................................................................... 368
Map Zone ..................................................................................................................... 369
US Stateplane Coordinate System 1983 ................................................................ 369
Universal Transverse Mercator .............................................................................. 369
UK National Grid ................................................................................................... 371
Geomagnetism .................................................................................................................... 372
Geomagnetic Main Field Models ................................................................................ 373
Factors that Influence Declination ......................................................................... 374
True, Grid, and Magnetic North ......................................................................................... 377
True north .................................................................................................................... 377
Grid north ..................................................................................................................... 377
Magnetic North ............................................................................................................ 377
Drillers Target Algorithm ................................................................................................... 380
References ......................................................................................................................... 383
Landmark COMPASS Training Manual 19
Chapter
Introduction
What is COMPASS?
The Computerized Planning and Analysis Survey System (COMPASS)
is a comprehensive software tool designed for use in directional well
design by either oil companies or directional contractors. COMPASS
for Windows is a tool that enables you to quickly and accurately plan
wells and identify potential problems at the earliest possible stage.
All of the features for complex well trajectory design, monitoring and
analysis are included. The list of features include survey & planning
methods, torque-drag optimization, anti-collision plotting with traveling
cylinder and ellipse of uncertainty.
COMPASS is designed to increase the efficiency and cost-effectiveness
of directional well planning and wellbore monitoring by providing an
easy-to-use interface and numerous other features. COMPASS enables
fast and accurate well planning and identification of potential directional
drilling problems at the earliest possible stage.
COMPASS enables you to:
� Design the shape of wellbores using the Planning Module.
� Calculate the shape of wellbores using the Survey Module.
� Calculate positional uncertainty and wellbore separation using the
Anti-Collision Module.
� Create hardcopy plots using the Wallplot Composer Module.
� Display results using various online graphics and hardcopy reports.
� Construct a data repository for storing deviation data that can be
linked to other data models.
The following technical features ensure that COMPASS is the most
comprehensive software of its kind available today:
1
Chapter 1: Introduction
20 COMPASS Training Manual Landmark
� Based on Landmark’s EDM database to provide seamless
integration with other Landmark Drilling software products such as
WELLPLAN, DIMS for Windows, StressCheck, and CasingSeat.
� Integration with Landmark’s OpenWorks applications, including
Wellbore Planner
� ODBC-compliant databases
� A logical, context-designed data model
� A consistent, easy-to-use interface
� Flexible units handling
� Comprehensive, context-sensitive online help written by engineers
� Comprehensive live graphical output
� Multi-component, customizeable plots with Wallplot Composer
� Formatted customizeable reports with ASCII file options
� Integrated planning and analysis work flow complemented by live
graphic updates
� Support for multiple depth datums per site
� Integration with industry-accepted Geodetic, Geomagnetic, and
Survey Tool Error models
� Customizeable survey tool error models
� Definition of targets with different geometry types
� Project Ahead and Varying Curvature Survey Analysis tools
� An easy-to-use planning tool with numerous 2D and 3D planning
solutions
� Improved horizontal well support with multiple target threading
� Curved Conductor/Slant rig support with configurable well
reference point.
� Multiple Anti-Collision Scan Methods and Graphical Outputs
Landmark COMPASS Training Manual 21
Chapter 1: Introduction
� Detailed Positional Uncertainty Error Surface Geometry calculation
and reporting
Modules
COMPASS consists of three main modules integrated by a host of
supporting features and an underlying data structure.
Survey
The Survey module calculates a Wellbore’s trajectory. Compass
considers a survey to be a set of observations made with a single survey
tool in the same tool run. Data can be entered in a spreadsheet or
imported and processed using industry-standard calculation methods.
The resulting survey files can be edited, printed or analyzed. Surveys
may be spliced together to form a definitive 'best path' using a tool
interval editor. Special provisions are made for Inertial and Inclination
only surveys. Survey provides an advanced "project ahead" from survey
station to target, formation or well plan.
Two methods enable you to assess survey data for incorrectly entered
survey data or bad readings from the survey tool. Input Validation will
isolate bad survey data as soon as it is entered. Varying Curvature
isolates incorrect survey station data by highlighting their inconsistency.
Survey analysis graphs are available that produce comparison plots of
survey and plan data for a number of different variables.
COMPASS survey data can be referenced to any number of user-
defined datums and can include a number of canned or custom formatted
report layouts that you can send to an ASCII file. You can also export
survey data to a raw survey file or output it to a number of canned or
custom export file formats.
Chapter 1: Introduction
22 COMPASS Training Manual Landmark
After you enter data, you can do the following:
� Perform point interpolations for any number of Measured or True
Vertical Depths, Inclination or Azimuths.
� Use the Project Ahead tool to compare the wellpath’s current
trajectory against a proposed target or plan.
� Perform Free Projections to a proposed MD or TVD using an
entered Build & Turn rate, Dogleg & Toolface, or by constructing a
trend using a number of existing survey observations.
Planning
Use the Plan Editor to design the shape of proposed wellbores. The
Planning environment has an interactive editing worksheet allowing the
user to build up the well trajectory in sections. There are many different
plan sections available for each section and they can be based on 2 or 3
dimensional Slant or S Shaped profiles or 3 dimensional dogleg/toolface
or build/turn curves. Alternatively the plan can be imported or entered
directly into the spreadsheet line by line. At each stage of well planning,
the user can see the Wellbore graphics dynamically update as changes
are made. The user may re-visit, insert or delete any section of a plan and
the whole plan will be recomputed.
The Wellbore optimizer integrates torque drag analysis into the
planning module. It will determine the best combination of trajectory
design parameters that lead to the minimum cost, anti-collision or torque
and drag solution. Planned designs which are 'un-drillable' by colliding
with other Wellbores or exceeding the drill strings tension, torque,
buckling, side force or fatigue limits are indicated.
Different plan methods are supported:
� Slant Well and S-Well designs are available to plan a well within a
vertical section.
� In 3D, you can construct plans using Build & Turn curves for
rotary-drilled sections or Dogleg/Toolface curves for steering tool-
drilled sections.
� You can also use additional tools such as Optimum Align, which
enables steering to be minimized to certain user-selected parts of
the well; Thread Targets, which automatically constructs a plan
through two or more targets using various plan types; and the
Landmark COMPASS Training Manual 23
Chapter 1: Introduction
Landing Calculator, which enables a plan to intersect a target plane
along a given azimuth.
� For long hold sections, a plan can be corrected for anticipated Walk
Rates through certain formations.
Anti-Collision
Anticollision can be used to check the separation of surveyed and
planned Wellbores from offset wells. Anticollision provides spider
plots, ladder plots, traveling cylinder, and printouts of well proximity
scans. Any anticollision scans may be run interactively with planning,
surveying or projecting ahead. All anticollision calculations are
integrated with Wellbore uncertainties that are shown on graphs or
reported as separation ratios. Warnings may be configured to alert the
user when the Wellbores converge within a minimum ratio or distance
specified by company policy.
Available Plots:
� Travelling Cylinder View: Wellpath separation referenced from
either high side of the well or high side + current well azimuth.
� Ladder View: MD vs. wellpath separation
� Separation Factor View: MD vs. Separation Factor
� 3D Proximity View: 3d presentation of all wells included in the
scan
� Spider Plot: Plan view of all wellpaths included in the scan.
� An Error Ellipse report that describes the geometry of the
uncertainty ellipsoid at all depths down the reference wellpath.
Who Should Use COMPASS
COMPASS is designed for engineers with different responsibilities and
for different types of organizations such as Oil Companies,
Directional/Survey Contractors, and Engineering Consultants. Different
users use COMPASS in different ways and work with different modules
within COMPASS according to their jobs requirements.
COMPASS enables an engineer to track a well through the following
stages:
Chapter 1: Introduction
24 COMPASS Training Manual Landmark
� The initial data-gathering stage, determining required geological
targets, surface drilling locations, planning constraints.
� The various phases of directional well design, including collision
avoidance, target analysis, operational stages of recording surveys,
checking for anti-collision risks, doing look-aheads, and
performing survey quality assessments.
� The compilation of a final definitive survey.
Within an Oil Company, a Well Planner plans a well to intersect one or
more targets provided by their Geoscience department. Targets are
analyzed and sized in conjunction with the design of the survey
program. The plan can be 2D or 3D and may require the use of rotary or
steerable bottom hole assemblies for it to be drilled. The plan is
communicated to and agreed upon by all concerned parties.
While drilling, the Rigsite Company Representative uses COMPASS to
enter and collate Survey data, report the Wellpath trajectory back to
town, and perform quality control checks on the data to ensure the
survey contractor obtains and records data correctly. In town, the
Operations Engineer in the Drilling Office receives the Survey data,
adds it to their COMPASS database, and shares it with other parts of
their organization or with partners.
Both engineers may perform Anti-Collision scans down the active well
to assess the collision risk. Also, they may compare the actual wellpath
trajectory with the directional well plan to ensure the well is on track. If
the well veers away from the Plan, they can do Back-On track
calculations to steer the wellpath back to its planned trajectory.
When the well is completed, the final Definitive Survey is composed,
locked, and made available for use with Anti-Collision scanning or
Sidetrack planning on future wells.
A Directional Contractor may use COMPASS to plan a well on behalf
of an Oil Company. At the rigsite, contract Surveyors and Directional
Drillers use COMPASS to enter Survey data as it is received at surface
or read on the drill floor, and a comparison is made with the planned
trajectory. The data is checked for errors and then reported to the Oil
Company representative in the form of reports, graphs, or wallplots.
The contractor can also provide the data electronically on floppy disk or
send it across a network. If their client also uses COMPASS, they can
send a transfer file to the Company Representative or Drilling Office.
Landmark COMPASS Training Manual 25
Chapter 1: Introduction
Directional Well Planners specialize in designing and assessing
wellpaths for a number of conditions.
In addition to planning wells through various targets and assessing the
plan for a collision risk, they use Geologic targets provided by the
Geoscience group to construct Drilling Targets. This is achieved using
survey tool error models applied down the planned wellpath to reduce
the size of the target surface. This enables the planner to design a cost
effective survey program applied to the given geological target sizes.
� A Survey Focal Point is responsible for maintaining an accessible
quality-checked survey database for an oil company. They can also
be involved in analyzing positional uncertainty error models
associated with different types of survey tools. Based on the
accuracy and reliability of different tools, they can recommend the
use of certain tools to the Well Planning group.
Licensing and Installation
There are three types of installations available for EDM applications:
� Local (Standalone) Installation: This type of installation is
appropriate for engineers needing to install EDM locally on a single
computer to be used by one person. This installation will copy the
product software, database, and all required support files to the
designated directory on the computer’s local hard drive. For more
information, please refer to the EDM Common Installation guide.
� Server (Network Server) Installation: This installation should be
used when the EDM applications will be installed centrally on a
server to be shared by a number of users. This installation will copy
the product software, database, and all required support files to the
designated shared directory on the network server. These files must
be accessible tot he network client computers. For more
information, please refer to the EDM Common Installation guide.
� Client (Network Client) Installation: This installation is used
when EDM applications will be run from the network. The client
installation will copy only the required system files to the local
computer’s hard drive and then create shortcuts to the shared
application executable files located in a designated directory on the
network server. For more information, please refer to the EDM
Common Installation guide.
Chapter 1: Introduction
26 COMPASS Training Manual Landmark
Licensing
FLEXlm is a licensing method common to all Landmark products. It
provides a single licensing system that integrates across PC and network
environments. FLEXlm Licensing files and FLEXlm Bitlocks are
supported for Landmark Drilling and Well Services applications. Please
refer to the EDM Common Installation guide for more information.
Landmark COMPASS Training Manual 27
Chapter
The Engineer’s Data Model (EDM)Database
Overview
Many of Landmark’s drilling applications use a common database and
data structure—the Engineer’s Data Model (EDM) database—to
support the different levels of data that are required to use Landmark’s
drilling and production software.
This is a significant advantage while using the software because of
improved integration between drilling software products. Currently
OpenWells, WELLPLAN, COMPASS, StressCheck, and CasingSeat use
the common database and data structure. Although the common
database improves integration between products, those products that
don’t use the common database can still share data using DEX.
In this chapter, you will be introduced to:
� Logging in to the database
� Data structure
� Common data
� Data locking
� Importing and exporting data
2
Chapter 2: The Engineer’s Data Model (EDM) Database
28 COMPASS Training Manual Landmark
Logging In To the Database
Any Landmark drilling software using the Engineer’s Data Model
(EDM) will require you to login. This dialog is used to select the
database and to provide a user id and password.
Starting COMPASS
You can start COMPASS in two ways:
� Use the Start Menu. Select COMPASS using Landmark EDM >
COMPASS.
� Double-click any desktop shortcut you have configured.
The following login screen appears when you launch COMPASS:
Select the database you want
to use from the drop-down
list.User will default to the
last user name entered.
Landmark COMPASS Training Manual 29
Chapter 2: The Engineer’s Data Model (EDM) Database
Describing the Data Structure
The EDM database has a hierarchical data structure to support the
different levels of data that are required by different drilling suite
applications. EDM uses the following hierarchical levels.
Hierarchical Level Description
Database The Database is the highest level in the Well
Explorer hierarchy. You can only work in one
database at a time. Refer to “Working at the
Database Level” on page 63 for more
information.
Company Company is the second highest data level in
the hierarchy. You can define several
companies within the database you are using.
Each company must have a unique name. If
you work for an operator, most likely you
may have only one company. If you work for
a service company, you may have several
companies. Refer to “Working at the
Company Level” on page 68 for more
information.
Company
Project
Site
Well
Design
Case
Wellbore
Company
Database
Hierarchical database structure of the
EDM database.
Chapter 2: The Engineer’s Data Model (EDM) Database
30 COMPASS Training Manual Landmark
Project Project is the data level directly beneath
company and each project within a company
must have a unique name. A project can be
thought of as a field or as a group of sites. A
project has one system datum (mean sea level,
lowest astronomical tide, etc.) that is used to
define 0 TVD for the project. Within the
project, wellbores can be referenced to the
project level system datum or to additional
datums specified at the well level. Refer
to“Using Datums in EDM” on page 50 or
“Working at the Project Level” on page 89 for
more information.
Site Site is the data level directly beneath the
Project level and each site within a project
must have a unique name. A site is a
collection of one or more wells that are all
referenced from a local coordinated system
centered on the site location. A site can be a
single land well, an offshore sub-sea well, a
group of well drilled from an onshore pad, or
a group of wells drilled from an offshore
platform. Refer to “Working at the Site Level”
on page 96 for more information.
Well Well is the data level directly beneath the Site
level and each well within a site must have a
unique name. A well is simply a surface
location. A well can have more than one
wellbore associated with it. For example,
there may be the original wellbore with one or
more sidetracks tied on to it at different kick-
off depths. Refer to “Working at the Well
Level” on page 108 for more information.
Wellbore Wellbore is the data level directly beneath the
Well level and each wellbore within a well
must have a unique name. A wellbore is a
compilation of one or more sections
originating at the surface and continuing to a
depth. A wellbore can be the original well
drilled from the surface or a sidetrack drilled
from a parent wellbore. If a well has an
original hole and two sidetracks, the well has
three wellbores. Refer to “Working at the
Wellbore Level” on page 115 for more
information.
Hierarchical Level Description
Landmark COMPASS Training Manual 31
Chapter 2: The Engineer’s Data Model (EDM) Database
Associated Components
There are several additional data components that are associated with
Designs or Cases. These are:
Design Design is the data level directly beneath the
Wellbore level and each design within a
wellbore must have a unique name. A design
can be thought of as a design phase.
Associated with each design are a pore
pressure group, a fracture pressure group, a
temperature gradient and a survey. A design
may have several cases associated with it, but
each case will use the same pore pressure
group, fracture pressure group, temperature
gradient and survey. A design can be
categorized as prototype, planned or actual.
You may have several different versions of
prototype designs. For example, assume the
geologist wants to analyze two different
formation fracture gradients. This could
easily be accomplished by having two
prototype designs that are identical except for
the fracture gradient group. Landmark’s
StressCheck and COMPASS applications
routinely use designs. Refer to “Working at
the Design Level” on page 120 for more
information.
Case (WELLPLAN only) Case is the data level directly beneath the
Design level and each case within a design
must have a unique name. A case can be
thought of as a snapshot of the state of the
well. For example, you may use two cases to
analyze the affects of varying the mud weight
or changing the BHA. Associated with each
case are an assembly, a hole section and one
or more fluids. Cases are commonly used in
Landmark’s WELLPLAN application.
StressCheck and COMPASS do not use cases.
Hierarchical Level Description
Chapter 2: The Engineer’s Data Model (EDM) Database
32 COMPASS Training Manual Landmark
Associated with Designs:
Wellpaths
A wellpath is a series of survey tool readings that have been observed in
the same wellbore and increase with measured depth. All Cases within
the same design use the same wellpath.
Pore Pressure Groups
A Pore Pressure group is a set of pore pressures that define the pore
pressure regime over a depth range from surface to some vertical depth.
All Cases within the same design use the same pore pressure.
Fracture Gradient Groups
A Fracture Gradient is a set of fracture pressures that define the fracture
gradient regime over a depth range from surface to some vertical depth.
All Cases within the same design use the same fracture gradient.
Geothermal Gradient Groups
A Geothermal Gradient is a set of undisturbed earth temperatures that
define the temperatures over a depth range from the surface to some
vertical depth. All Cases within the same design use the same
geothermal gradient.
Associated with Cases:
Hole Section Groups
A Hole Section defines the wellbore as the workstring would see it. For
example, a hole section may contain a riser, a casing section, and an
open hole section. A hole section can also have a tubing section or a drill
pipe section depending on the situation. Multiple cases may use the
same hole section.
Assemblies
An Assembly defines the workstring. There are several types of
workstrings, including coiled tubing, casing, drillstrings, liners, and
tubing strings. Multiple cases may use the same assembly.
Landmark COMPASS Training Manual 33
Chapter 2: The Engineer’s Data Model (EDM) Database
Fluids
A Fluid defines a drilling, cementing, or spacer fluid. A Fluid is linked
to a Case and a Case can have more than one fluid linked to it. One fluid
can be linked to multiple cases.
Copying and Pasting Associated Items
All of these associated items, with the exception of fluids, are
automatically created and associated ("linked") by Well Explorer to the
design or case. (You cannot manually create or link these items.) Fluids
can be created/linked in WELLPLAN only, using the Fluid Editor.
However, all these items are visible in Well Explorer so that you can
copy and paste them using the right-click menu. For example, when you
copy a wellpath and paste it into a different design, the wellpath that
currently exists for the target design is deleted. Well Explorer replaces
the old wellpath with the copy of the new one.
Again, fluids are the exception. Only the WELLPLAN Fluid Editor can
delete fluids, so after pasting a fluid, the original fluid still exists. The
original fluid is no longer linked to anything. This can’t be seen in Well
Explorer, but WELLPLAN can access this. Note that if the destination
case, or the fluid you are trying to replace, is locked, a message appears
and the paste is not completed.
Rules for Associating Components
The rules for associating components are listed below.
For Definitive Surveys, Pore Pressure Groups, Fracture Gradient
Groups, Geothermal Gradient Groups, Assemblies, and Hole Sections:
� Each component can only be associated with one Design or Case.
� When one component is copied and pasted, an actual copy is made.
� When one component is pasted, the component is replaces will be
deleted (unless it is locked).
� If the destination for the paste is locked (Design or Case) or the
item to be replaced is locked, a message appears and the paste is not
completed.
� If the design is locked, all it’s associated items are also locked.
Chapter 2: The Engineer’s Data Model (EDM) Database
34 COMPASS Training Manual Landmark
For Fluids:
� When a fluid is copied and pasted, an actual copy is made.
� When a fluid is pasted, the one is replaces will NOT be deleted.
� Fluids can only be deleted using the Fluid Editor in WELLPLAN.
� If the destination case is locked or the fluid to be replaced is locked,
a message appears and the paste is not completed.
Landmark COMPASS Training Manual 35
Chapter 2: The Engineer’s Data Model (EDM) Database
Common Data
Common data stored in the EDM database and available for use by
StressCheck, CasingSeat, WELLPLAN, Openwells, and COMPASS in
database mode include:
• Unit system
• Pipe catalog
• Connections catalog
• Pore pressure
• Fracture Gradient
• Temperature Gradient
• Surveys
• All fields in Well Explorer Properties dialogs
• General data, such as Well Name, Well Depth, Vertical Section
information
Note: Several additional fields are common to two or more applications, but not all.
Drilling applications may share other data not listed.
Chapter 2: The Engineer’s Data Model (EDM) Database
36 COMPASS Training Manual Landmark
Data Locking
You can prevent other people from making changes to data by locking
data at various levels and setting passwords. Users can only open the
data item in read-only mode; to keep changes, they will have to use
Save As or Export.
How Locking Works
You can lock Company properties only, or you can lock properties for
all levels below Company (Project, Site, Well, Wellbore, Design, and
Case). Passwords can be set to prevent unlocking.
By default, no passwords are set, and the "locked" check box on all
Properties dialogs can be toggled on and off at will with no security to
prevent users from doing something they shouldn’t.
In the Well Explorer, if a data item is locked a small blue "key" appears
in the corner of its icon. When you open a locked data item, you will see
the message "This Design is locked and therefore Read-Only. Changes
to this Design will not be saved to the database. To keep your changes,
use the Save As or Export options."
Locking Company Properties
In the Properties dialog for the company whose data you want to protect,
there are two buttons, Company Level and Locked Data, and a
checkbox, Company is locked.
When you click the Company Level button, you are prompted to set a
password to protect Company properties (and only the Company
properties). This password will then be required if a user wants to
"unlock" company properties and make changes.
Once the password is set, toggle the Company is locked checkbox on to
lock the company properties and prevent unauthorized changes to the
data.
Locking Levels Below Company
When you click the Locked Data button on the Company Properties
dialog, you are prompted to set a password. This password will then be
Landmark COMPASS Training Manual 37
Chapter 2: The Engineer’s Data Model (EDM) Database
required if a user wants to "unlock" any level below the company
(projects, sites, wells, wellbores, designs, and cases).
All levels are locked individually—that is, you can lock a Well, but this
doesn’t mean that anything below it is locked.
Once the Locked Data password is set, you can lock properties for any
data level below Company and prevent unauthorized changes to the
data. Open the Properties dialog for the data level you want to lock and
toggle the "locked" checkbox on. (For example, to lock a Wellbore,
open the Wellbore Properties dialog and toggle Wellbore is locked on.)
Note: Locked Designs...
When a design is locked, all associated items (Pore Pressure, Fracture Gradient,
Geothermal Gradient, and Wellpath) are locked with it.
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Concurrent Use of Same Data By Multiple Users
The 2003.5 release of EDM supports concurrency for multiple users on
the same data set. The Simultaneous Activity Monitor (SAM) is the
service used to regulate concurrent access to the EDM database. For in-
depth information on SAM, refer to the EDM Administration Utility
help.
� By default, the SAM server is enabled and connected and you will
see a green "SAM" icon in the status bar of your application.
� If the SAM service is configured but not connected, the "SAM"
icon will appear with a red "X" drawn through it. Consult your
System Administrator.
� If the SAM service is not configured, there will be no SAM icon in
the status bar.
A good practice for any multi-user environment is to frequently use the
F5 refresh key to refresh the Well Explorer contents. Data updates (e.g.,
inserts, updates, deletions) are not always automatically recognized in
other EDM sessions and simultaneously run EDM applications.
How the Well Explorer Handles Concurrent Users
Basically, the Well Explorer and the Simultaneous Activity Monitor
handle concurrency like this: If a user on a different machine has a
Design open (first one to open the Design gets it in Read/Write mode),
then all other users can only open that Design in Read-Only mode. If no
one on any other machine has Read/Write access to the Design, then you
get Read/Write access.
This is the SAM icon:
The red "SAM" icon indicates that one or more users have this item open
and you are restricted to opening it in Read-Only mode. You cannot save
any changes to the database, but you can use Save As and rename the
item.
The blue "SAM" icon indicates that one or more users have this item
open, but you can still open it in Read/Write mode. You can save
changes to the database.
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Chapter 2: The Engineer’s Data Model (EDM) Database
These SAM icons will appear on a Design (COMPASS, WELLPLAN,
StressCheck, CasingSeat) or a Well (OpenWells) in the Well Explorer.
Same User on Same Computer
If the same user has a Design open in one EDM application and then
opens the same Design in another EDM application on the same
machine, the blue "SAM" icon will appear in the Well Explorer of the
second application. This indicates that this user has the Design "locked
for use in Read-Write mode", and has it open in more than one
application. However, because it IS the same user, he/she can Save
changes to the database made from either application.
Multiple Users, Different Computers
The first user to open a Design or Case in that well gets control, and the
Design or Case is then "locked for use in Read/Write mode." A red
"SAM" icon indicates that more than one user is working with the
Design or Case at the same time. However, only the first user can make
changes; all other users open the Design or Case in Read-Only mode.
They can Save As, but not Save.
After the user who had access to the Design or Case in Read/Write mode
closes the Design or Case, the red "SAM" icon goes away, and the
Design or Case is available again. Read-only users will have to close the
Design or Case and re-open to gain control.
(WELLPLAN only) A user can save Cases under a Design that is
currently "locked for Read/Write use" by someone else.
Reload Notification
If you are working with any of the data in the following list, and a user
with read/write privileges saves changes to the database, you will
receive a notification indicating that another user has changed the data
you are working with.
You will have the opportunity to use the changes saved to the database
by the other user. You will also have the opportunity to save the data you
are working with using the Save As option. If you do not save your data
using Save As, your changes will be overwritten by those made by the
other user. (Your changes will only be overwritten if the other user saves
his changes, and you indicate you want to use those changes when you
receive notification.) Keep in mind that if you have read privileges, any
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40 COMPASS Training Manual Landmark
changes you make are only stored in memory and are not written to the
database unless you save your data using Save As.
Items that are refreshed in this manner are: Design, Definitive Survey
(Wellpath), Pore Pressure, Fracture Gradient, Geothermal Gradient,
Assemblies (Casing Scheme)
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Chapter 2: The Engineer’s Data Model (EDM) Database
Simultaneous Activity Monitor (SAM)
The 2003.5 release of EDM (the Engineer's Data Model) supports full
concurrency for multiple applications using the same data set through
the Simultaneous Activity Monitor (SAM).
If the Simultaneous Activity Monitor has not been configured, the
following message will appear: "WELLPLAN could not connect to the
SAM server. Please verify that the settings are configured correctly in
the administration utility, and that the SAM server is running."
The Simultaneous Activity Monitor consists of a Messaging Server that
notifies the user with an open application of all data currently open in
other applications. The SAM icon appears in the application Status Bar
as follows:
If a data item is open, an icon will appear as follows:
� A red SAM icon indicates that one or more users on other PC’s
have this item open and the current user is restricted to read-only
access.
� A blue SAM icon indicates that one or more users on the current PC
have this item open but the current user still has full read-write
access. A user must be careful when making changes to the date
though this method enables data to automatically flow between
applications.
Icon Message Description
A green SAM icon in the status bar indicates that the
Messenger service is active.
A blue SAM icon with a red X on it indicates that the
Messenger Service is not currently active.
No Icon When no icon appears in the application status bar this
indicates that the Simultaneous Activity Monitor has not
been configured for the application.
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Importing and Exporting Data
COMPASS provides you with EDM database import and export
functionality, as well as DEX file import and export functionality.
Importing Data into the EDM Database
You can import data from one EDM database into another EDM
database, or you can import a DEX file.
Importing EDM Well Data from Another Database
To import well data from one EDM database to another, follow these
steps:
1. In the Well Explorer, select the EDM database canister.
2. From the Well Explorer right-click menu, select Import. The
following dialog box opens:
3. Select the .XML file containing the well data you want to import,
and click Open. (Well data can be saved in .XML format using the
Export command in the Well Explorer; see page 44 for details.)
4. The well data will be imported into the database.
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Chapter 2: The Engineer’s Data Model (EDM) Database
Importing a DEX File Into the Database
To import a DEX file into the EDM database, follow these steps:
1. Select File > Data Exchange > Import. The following dialog box
opens:
2. Specify the filename for the well information in DEX format you
want to import, and click Open. The following dialog appears.
3. Use the arrow buttons to move the desired data items into the lower
list box. Single arrow buttons move the highlighted file(s). Double
arrow buttons move all files. (Use the upward facing arrows to
remove items from the desired selection.)
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4. Click OK to start the import.
5. The data will be imported into memory and displayed in the main
window. The data has not yet been saved to the database. You may
make changes now, if you wish.
6. When you are ready to save the changes to the database, select
File > Save. The Save As dialog opens, allowing you to specify
where in the hierarchy to place the newly imported design, and to
name the design. Click Save. The newly created design will appear
in the Well Explorer tree.
Exporting Data From the EDM Database
You can export well data from the EDM database in .XML format; this
data can then be imported directly into another EDM database. You can
also export data in DEX format.
Exporting Data in XML Format
To export well data for import into another database, follow these steps:
1. In the Well Explorer, select the company, project, site, well,
wellbore, design, or case whose data you want to export and right-
click to open the pop-up menu. Select Export. The following
dialog box opens:
2. Specify a filename for the information you want to export, and click
Save. The parent and child data, and any linked pore pressures,
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Chapter 2: The Engineer’s Data Model (EDM) Database
fracture gradients, etc. will be saved to the .XML file you
specified.
Exporting Well Data in DEX Format
To export well data as a DEX (.DXD) file, follow these steps:
1. Select File > Data Exchange > Export from the main menu. The
following dialog box opens:
2. Specify a filename for the well information you want to export in
DEX format, and click Save. If this is the first time you have saved
DEX data using the specified filename, the export is complete at
Note: Exporting a Large Number of Wells
There may be problems when exporting a company with a large number of wells.
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46 COMPASS Training Manual Landmark
this point. If the specified file already existed, the following dialog
opens to allow you to specify which objects you want to export.
3. Use the arrow buttons to move the desired data items into the lower
list box. Single arrow buttons move the highlighted file(s). Double
arrow buttons move all files. (Use the upward facing arrows to
remove items from the desired selection.)
4. Click OK to start the export. The data will be saved to the .dxd file
you specified.
Wellbore Planner Import / Export
Wellbore Planner is a well planning application integrated into
Landmark’s Geological and Geophysical visualization UNIX
applications. Links with COMPASS enable Wellbore Planner users
(Geologists/Geophysicists) to quickly construct well trajectories with
COMPASS users (drillers), with both using their own data sets. This
reduces planning time by eliminating the paper stage in which
geologist’s targets details are written down, passed to the driller, and
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Chapter 2: The Engineer’s Data Model (EDM) Database
their resultant wellpath trajectory is then copied back and forth until a
final trajectory is agreed upon.
COMPASS can import and export data directly to Wellbore Planner.
This route also enables selective import of Openworks well trajectories.
This type of tool enables Planned Trajectory or Actual Trajectory data
to be easily shared between the Engineering and Geoscience disciplines.
Wellbore Planner Import
This feature allow you to import ‘*.WBP’ files from the Wellbore
Planner application. The file has to be moved to the Windows
COMPASS computer by FTP link.
These are the import rules:
• If you are moving the data to an existing Company, Field, or Site,
open them before the import.
• If you don’t want the import to interfere with existing data, open a
new company. To open the File Open dialog, from the COMPASS
main menu click File, Import, then Wellbore Planner. Select the
file to import (*.WBP).
If you are importing to an existing site, a message box appears
displaying the following:
If you have already chosen a site, the following message appears:
Importing file xxxx.wbp to site yyyy, click OK to
continue.
If the Map coordinates contained in the Wellbore Planner file disagree
with the current site, or disagree within itself, the message ‘Well xxxx
has strange starting coordinates’appears. The data is still imported, but
you must check it.
Click this... To import this...
All Data All data
WP Plans Wellbore Planner plans only
OW Wells OpenWorks wells surveys
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Wellbore Planner Export
This feature exports a file in the Wellbore Planner format for import to
a geological application like OpenVision. The file has to be moved from
the COMPASS for Windows PC via FTP. In COMPASS, open the
Customer, Field, and Site of interest. Then, from the COMPASS main
menu, select File, Export, then Wellbore Planner. COMPASS then
asks the name and destined location of the export file.
DIMS for Windows Survey Import
DIMS for Windows (DIMS) is Landmark’s Drilling and Well Services
Daily Drilling and Completions Reporting System. Typically DIMS is
used at the rigsite as part of a client’s daily drilling reporting procedure.
Built-in links between COMPASS and DIMS for Windows enables easy
transfer of survey information from DIMS to COMPASS to reduce
survey data-entry duplication.
To access the DIMS survey import tool, you must open a wellpath in
COMPASS to import surveys into. The DIMS survey import also
requires an ODBC data source that you use to access the DIMS for
Windows database. A database connection is the PC’s mappings of how
software applications should open a database. Both COMPASS and
DIMS for Windows require defined ODBC connections before the
applications run. Consult your systems administrator to build a DIMS
for Windows ODBC data source if one is not available.
Well
Select a DIMS well from the drop-down list. COMPASS populates the
SideTrack list box with the sidetracks for that well defined within
DIMS.
Sidetrack
Select a DIMS sidetrack for COMPASS to import Surveys from. Each
unique survey tool within DIMS for the sidetrack will be displayed in
the Tool Mappings grid.
Tool Mappings
The DIMS survey tools must be mapped to equivalent COMPASS
survey tools. This is necessary because there is no connection between
them, and COMPASS requires a correct tool mapping to calculate
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Chapter 2: The Engineer’s Data Model (EDM) Database
positional uncertainty. You must do this for all DIMS tools before
starting the import. COMPASS remembers survey tool mappings for
future use.
When mappings are complete, press OK, and COMPASS imports the
DIMS for Windows data, creating a separate survey for each one of the
mappings.
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Using Datums in EDM
Definition of Terms Associated With Datums
Datum terms are defined below, and are grouped by the Properties
dialog in which they are found.
Project Properties
System Datum:
The System Datum is set in the Project Properties/General dialog, and
represents absolute zero. It is the surface depth datum from which all
well depths are measured, and all well depths are stored in the database
relative to this datum. Usually the System Datum is Mean Sea Level,
Mean Ground Level, or Lowest Astronomical Tide, but it can also be the
wellhead, rigfloor, RKB, etc.
Elevation:
The Elevation is set in the Project Properties/General dialog, and
represents the elevation above Mean Sea Level. (If Mean Sea Level is
selected as the System datum, Elevation is grayed out.)
Well Properties
Depth Reference Datum(s):
The Depth Reference Datum represents zero MD. It is sometimes
known as the local datum, and is measured as an elevation from the
System Datum. You can define one or more Depth Reference Datums
for a well in the Depth Reference Tab (Well Properties Dialog). For each
Depth Reference Datum, you must specify the elevation above or below
the System Datum.
The selected default Depth Reference datum in the list box will be the
viewing datum in all applications (the viewing datum can be changed
‘on the fly’ only in OpenWells and COMPASS.)
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Chapter 2: The Engineer’s Data Model (EDM) Database
You can’t delete or change the elevation of a Depth Reference datum
once it is referenced by a Design.
Offshore check box:
Check to indicate that this is an offshore well; leave unchecked to
indicate a land well.
Subsea check box: (offshore well)
Check to indicate that this offshore well is subsea.
Ground Elevation: (land well)
This is the elevation of the ground above the System Datum; it is set in
the Depth Reference Tab (Well Properties Dialog).
Water Depth: (offshore well)
This is the total depth of the column of water (MSL to mudline); it is
referenced to Mean Sea Level.
Mudline Depth: (only for offshore subsea well)
This is the depth below system datum (MSL/LAT etc.) of the wellhead
flange.
Wellhead Depth: (subsea well)
This is the distance from the wellhead to the system datum, and is used
in some calculations where this is the hanging depth for casing leads
when set. To determine wellhead depth:
Wellhead Depth (to rig floor) = Depth Reference Datum + Wellhead
Depth
Wellhead Depth (set in the Well Properties/General dialog) is positive
for offshore subsea and negative for wellheads above MSL (i.e., onshore
or offshore platform). So, it does not matter in the above calculation
whether it is offshore or subsea. Depth Reference Datum is always
positive. Both wellhead depth and wellhead elevation are distances from
the system datum to the flange.
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Wellhead Elevation: (platform and land wells)
This is the height above system datum (MSL/LAT) of the wellhead
flange (surface casing). It may happen that for some land wells using
ground level as the system datum that the user may have to enter a
negative value because the wellhead 'cellar' is often below the ground.
Air Gap (calculated)
This is the distance from the system datum to the rig floor, and is used
in some calculations for hydrostatic head. Air Gap is always positive. To
calculate air gap, the application uses:
� Air Gap (offshore wells) = Depth Reference Datum – Elevation
� Air Gap (land wells) = Depth Reference Datum – Ground Level
Elevation is set in the Project Properties/General dialog. Ground Level
is set in the Well Properties/ Depth Reference dialog.
Design Properties
Depth Reference Information:
From the drop-down list of defined Depth Reference datums, select the
datum you want to reference for this Design. Once you select a datum,
the Datum Elevation, Air Gap, current System Datum, Mudline Depth,
and Mudline TVD are all updated/calculated and displayed adjacent to
the rig elevation drawing on the Design Properties box,
Setting Up Datums for Your Design
1. Project Properties > General dialog - Select the System Datum you
want to use.
2. Project Properties > General dialog - In the Elevation field, enter
the value the System Datum is above Mean Sea Level. If your
System Datum is below Mean Sea Level, this number will be
negative. If your System Datum is Mean Sea Level, Elevation is
grayed out.
3. Well Properties > Depth Reference dialog - If the well is offshore:
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Chapter 2: The Engineer’s Data Model (EDM) Database
a) Check Offshore, and enter the Water Depth below the System
Datum.
b) If the well is subsea, check Subsea and enter the Wellhead Depth
below the System Datum.
4. Well Properties dialog, Depth Reference tab - If the well is a land
well, make sure Offshore is unchecked, and enter the Ground Level
elevation above the System Datum.
5. Well Properties dialog, Depth Reference tab - Define the Depth
Reference Datum (s) you want to use, such as RKB or Rigfloor.
Type the elevation above the System Datum in the Elevation field,
and specify the effective Date for the datum.
6. Import or create a design for this well.
7. In the Design Properties dialog, General tab, select the Depth
Reference Datum you want to use for this design from the drop-
down list of datums you defined in Step 5.
Changing the Datum
(WELLPLAN Only) If a Design was created using one Depth Reference
datum, and the Depth Reference datum is changed, then when the
Design is opened any depths that become negative will be changed to
zero, and all depth-related properties will be adjusted accordingly.
(StressCheck and CasingSeat Only) When you create a design and save
it for the first time, the EDM database keeps track of the Depth
Reference Datum that was set at the time. This "original" Depth
Reference Datum is not displayed; however, if you or someone else
changes the Depth Reference Datum in the Well Properties dialog, and
you then attempt to open that design, a warning message will appear.
You are warned that you are trying to change to a datum that is different
from the datum in which you originally saved the data, and any
calculations will be invalid unless you change your inputs (see details
here). You are given the choice to open the design/case in the original
datum, or to convert to the new datum. If you choose to convert your
data, the data will be adjusted. However, the change is NOT saved to
the database until you save the design, at which time the new datum
becomes the "original" datum.
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How this works:
If datum is same as original datum:
If you open a design or case where the Depth Reference Datum (set at
the Design level) is the same as the datum the data was originally saved
in, the design/case will open normally.
If datum is different than the original datum:
If you open a design or case where the Depth Reference Datum (set at
the Design level) is different from the original datum, the following
occurs:
1. The application checks to see if the well is a slant hole. If positive
inclination exists in wellpaths whose depths would become negative
after the datum shift, the program cannot make the adjustments; a
message pops up to inform you of this. Click Open to open the
design in the original datum; if you click Cancel, the design will not
open at all.
2. For wells other than slant holes, the program will issue this
message: "The currently selected design datum is different to the
datum with which the design was created. The application will then
attempt to adjust the data, but some data might be shifted or
removed. If you open the design, we strongly suggest that you
review your input data; any changes will not be saved to the
database until you explicitly save your data. Please select "Open" to
review the design using the datum with which it was created."
If you want to open the Design with the original elevation, select
Open. If you want to convert the data to the new elevation, select
Adjust. Open is the default.
• If you enter "Open": Data is loaded to the original design datum,
but the Depth Reference Datum set in the Design will NOT
change to match the original datum.
• If you enter "Adjust": Well Explorer loads the data to the new
Wellbore datum and attempts to adjust the data; however, some
data may be shifted or removed. The program will resolve the
deltas in the first depths of column data (strings, wellpaths,
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Chapter 2: The Engineer’s Data Model (EDM) Database
columns, etc.) to adjust for the new gap and read zero depth on
the first line.
Note: After Opening a Design...
Once you open the design you should review your input data; remember that the
changes will not be saved to the database until you explicitly save your data.
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Landmark COMPASS Training Manual 57
Chapter
Using the Well Explorer
Overview
In this chapter, you will become familiar with using the Well Explorer.
You will expand your knowledge of the hierarchical levels of the EDM
database discussed in the last chapter.
In this section of the course, you will:
� Become familiar with the components of the Well Explorer
� Become familiar with the data levels accessible using the Well
Explorer
� Become familiar with the items associated with each data level
3
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58 COMPASS Training Manual Landmark
Introducing the Well Explorer
In COMPASS, the Well Explorer is located in the right pane area of the
application window (this differs from other drilling applications, such
as WELLPLAN, where it is located by default on the left side of the
application window). Well Explorer functions much like the Microsoft
Windows Explorer. It is organized as a hierarchical data tree. You can
browse the EDM database at five hierarchical levels: Companies,
Projects, Sites, Wells, Wellbores, and Designs.
Well Explorer
Currently selected data
item (a prototype design)
Database
Canister
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Chapter 3: Using the Well Explorer
Use the Well Explorer to:
• Browse, open, copy, delete, create, and otherwise manipulate the
main data items. The currently open item is highlighted. Details of
the data hierarchy are discussed in “Describing the Data Structure”
on page 29.
• "Drag and drop" data between hierarchical levels. For example,
you can select a Project associated with one Company, and copy it
to another Company. When you copy the Project, all the data
(Sites, Wellbores, etc.) associated with the Project are also copied.
Well Explorer Components
The Tree
The hierarchical tree functions much like the Microsoft Windows
Explorer. You can view and manipulate different levels within the
EDM data model hierarchy, in a fashion similar to a directory tree.
Operations are:
• Left mouse button is used to expand or contract branches of the
data tree and to select. Click the + sign to expand the hierarchy and
click the - sign to contract it.
• The right mouse button has a context-sensitive menu. Depending
on the hierarchical level you have highlighted (Company, Project,
Sites, Wells, Wellbores, Wells, Design, Cases, Wellpaths, Pore
Pressure Groups, Fracture Gradient Groups, Geothermal Gradient
Groups, Hole Section Groups, Assemblies, Fluids and Catalogs)
the menu will populate with the relevant options. (New data item,
New Attachment, Copy, Paste, Delete, Properties, etc).
Note: The Well Explorer display will vary slightly from one
application to another.
Applications that do not use Cases (such as StressCheck and COMPASS) will not
display Cases in their Well Explorer.
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Associated Data Components
Data components that can be associated with a design or case are
displayed in the Associated Data Viewer at the base of the Well
Explorer.
Data Components Associated with a Design
Data components that can be associated with a design are: Attached
Documents, Fracture Gradient Groups, Pore Pressure Groups,
Geothermal Gradient Groups, and the Wellpath associated with the
design. Refer to “Associated Components” on page 31 for more
information.
The Recent Bar
To save time, you can use the Recent bar to select a recently used
Design instead of browsing for the desired item in the Well Explorer.
Displaying/Sizing the Well Explorer and Recent Bar
In Compass, the components of the Well Explorer are always
displayed. However, you can customize the size of the Well Explorer
two ways. To change the size of the Well Explorer:
� Maximize or minimize the Well Explorer by clicking the
Maximize/Minimize button
� Resize the Well Explorer by using your mouse. To do this, use the
mouse to position the cursor over a Well Explorer border. The
To display the list of recently used designs, wellbores, or
projects, etc., click on the drop-down list. Select the item
you want to use from the list, and it will be displayed in the
main window.
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Chapter 3: Using the Well Explorer
cursor changes from a singe arrow to a horizontal double-arrow.
Left-click and drag to alter the size of the Well Explorer.
Positioning the Well Explorer
If the Well Explorer is in the restored state, you can reposition it with
your mouse. Move the cursor to the top blue border, left-click, then
drag the Well Explorer to the area you prefer.
Tracking Data Modifications
In COMPASS, you can track modification of data using the Audit
Information tab (on the Properties dialog for each data type).
Using the Well Explorer, right click on a data type icon to display the
right-click menu items. Select the Properties to display the Properties
dialog, then click the Audit Information tab to display it. This tab
provides information on the data modifications for this item.
This information indicates who created the
company, project, site, well, wellbore,
design, etc. Also displayed is the date the
item was created as well as the application
that was used to create the item. This information indicates
who modified the company,
project, site, well, wellbore,
design, etc. Also displayed
is the date the item was
modified as well as the
application that was used to
modify the item.
Type comments as
desired to assist with
tracking the use of the
software. New
comments are
appended to existing
comments.
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Drag and Drop Rules
"Drag and drop" in the Well Explorer functions somewhat like the
Microsoft Windows Explorer. You can use drag and drop to copy
Companies, Projects, Sites, Wells, Wellbores, Designs, Cases, as well as
associated data items and attached documents.
All drag and drop operations copy the data; data is never cut or moved.
� To copy - Drag and drop the item to copy it from one location and
paste it into another. The item and all associated data will be copied
and pasted.
You can drag and drop associated items (Wellpaths, Pore Pressures,
Fracture Gradients, Geothermal Gradients, Hole Sections, Assemblies,
etc.) into open Designs or Cases from the Associated Data Viewer at the
base of the Well Explorer. The application will automatically update
itself with the copied data.
Some rules:
� You cannot drag and drop an Actual Design. However, if you copy
a Wellbore, any Actual Designs under that Wellbore are copied.
This is also true for copying done at the Well, Site, Project, and
Company level.
� You cannot drag a Wellpath from the Associated Data Viewer into
an Actual Design.
� If you drag a Planned or Prototype Design to a different Project,
targets will not be copied with the Design. As a result, the plan will
no longer have any targets associated with it.
� Depending where a Design sidetrack Wellbore is dropped, Plan and
Survey tie-on information may be lost, and as a result, survey
program may be missing information.
� (COMPASS only) If a Survey is dropped onto a Wellbore or Actual
Design in another Company, the Survey will lose its tool
information.
� You cannot drag and drop Catalogs. Instead, you must use the right-
click menu Copy and Paste functions
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Chapter 3: Using the Well Explorer
Well Explorer Right-Click Menus
When you click on something in the Well Explorer (a Well, Design,
etc.), right-clicking brings up a menu of options pertinent to that
hierarchical level. The options on each hierarchical level are discussed
below.
Working at the Database Level
When a Database is selected on the Well Explorer, the following right-
click menu items are available:
Command Description
Open Opens the selected database.
New Company Choosing this option displays the Company Properties dialog.
(page 64)
Instant Plan Use Instant Plan to quickly create a new plan. Choosing this
command displays the Instant Plan dialog box, which allows you
to quickly select the hierarchy you want -
Company, Project, Site, Well, Wellbore, and Plan - from drop-
down lists of existing database entries. After making your selec-
tions, click OK to create the Plan. (page 64)
Instant Survey Use Instant Survey to quickly create a new survey. Choosing this
command displays the Instant Survey dialog box, which allows
you to quickly select the hierarchy you want - Company, Project,
Site, Well, Wellbore, and Survey - from drop-down lists of exist-
ing database entries. After making your selections, click OK to
create the survey. (page 64)
Well Name Choosing this option displays a sub menu from which you can
select how to name the wells in your project. (page 65)
Wellbore Name Choosing this option displays a sub menu from which you can
select how to name the wellbores in your project. (page 65)
Lithologies Choosing this option displays the Lithologies Editor. Use the
Lithology Editor to configure bitmaps to Lithology names that
may then be used in formation columns for section views.
(page 66)
Import The Import command allows you to import a Well into the data-
base that was exported using the Export command. See “Import
(Database Level)” on page 67 for more information. (page 67)
Search Use this command to display a dialog that enables you to search
for a particular data component in the EDM database. (page 67)
Refresh Use this command to refresh (update) the Well Explorer tree
with any changed information. Pressing the F5 key is another
way to refresh. (page 68)
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64 COMPASS Training Manual Landmark
New Company (Database Level)
To create a new company, select the database canister and right-click;
select New Company. The Company Properties dialog opens. Refer to
“Properties (Company Level)” on page 81 for more information on
using the Company Properties dialog.
Instant Plan (Database Level)
Use this dialog to quickly and easily create the hierarchy required to
start a plan, from the company all the way down to the wellbore. This
allows you to enter minimal information and the effort of going through
the individual property dialogs at each level of the hierarchy.
Instant Survey (Database Level)
Use this dialog to quickly and easily create the hierarchy required to
start a survey, from the company all the way down to the wellbore. This
Expand All To expand all levels below the Database level. (page 68)
Collapse All Use this command to collapse all levels below the Database
level. (page 68)
Select the Company, Project, and Site from
the drop-down list of existing companies,
projects, or sites. You can also enter a new
name for the data level.
Enter the name of the Well,
Wellbore, and Plan.
Use the pull-down menu to select a
Geodetic System. This is the general
mapping system, e.g. "Universal
Transverse Mercator."
If available, use the pull down menu
to select the Geodetic Datum. This
defines the center and radii of the
projection in this location, e.g.
"ED50". Use the pull down menu to
select the zone within the
system, e.g. "UTM Zone
31, North 0 to 6 E".
Enter the map co-
ordinates of the site center
location based on the
Geodetic System selected
above.
Landmark COMPASS Training Manual 65
Chapter 3: Using the Well Explorer
allows the user to enter minimal information and saves them from
having to go through the individual property dialogs at each level of the
hierarchy.
Well Name (Database Level)
Choosing this option displays a sub menu from which you can select
how to name the wells in your project. The options are:
� Common Name - Short/abbreviated well name given to well for
day-to-day reference.
� Legal Name - Formal well name assigned for documentation
purposes.
� Universal Identifier - A coded well name that varies from region to
region.
� Slot Name – Post-fixes the chosen well name with the slot name if
available.
Note: You can choose only one of the naming options Common Name,
Legal Name, or Universal Identifier. You can use Slot Name in
conjunction with the other naming conventions.
Wellbore Name (Database Level)
Choosing this option displays a sub menu from which you can select
how to name the wellbores in your project. The options are:
Refer to “Instant Plan (Database Level)” on
page 64 for information on dialog entry.
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66 COMPASS Training Manual Landmark
� Common Name - Short/abbreviated well name given to well for
day-to-day reference.
� Legal Name - Formal well name assigned for documentation
purposes.
� Universal Identifier - A coded well name that varies from region to
region.
Note: You can choose only one of the naming options Common Name,
Legal Name, or Universal Identifier.
Lithologies (Database Level)
The Lithologies command displays the Lithology Editor dialog. Use this
dialog to configure bitmaps to Lithology names that may then be used
in formation columns for section views.
To define a lithology using the Lithology Editor
1. Enter a Lithology Name in the left column grid. This name must be
unique.
2. Select a lithology texture by pressing the browse button (labelled
‘:’) and then choosing a bitmap file using the File > Open dialog.
You may observe the selected texture in the area below the grid.
3. Repeat steps 1-2 until the required set is complete.
4. Click OK and the lithology list will be saved.
The texture sample
for the selected item
is shown here.
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Chapter 3: Using the Well Explorer
Import (Database Level)
The Import command allows you to import a Well into the database that
was exported using the Export command. The import file is in .XML
format, and contains the entire hierarchy of the Well (Company,
Project, and Site, and well as any child data, such as Wellbore, Design,
etc.)
When you select Import, the Import well dialog opens, prompting for
the .XML filename to import. Type the filename, or browse for the file.
Click Open. The Well hierarchical data will be imported into the EDM
database.
Search (Database Level)
Use this command to display a dialog that enables you to search for a
particular data component in the EDM database.
Select the data level you
are searching for from the
drop-down list.
Specify the search criteria using this grid.
Refer to the online help for a description of
the operators.
Check the box
associated with
the field you
want to base the
search criteria
on. Notice that
the checked
items are
displayed in the
grid.
Search results are displayed here.
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68 COMPASS Training Manual Landmark
Refresh (Database Level)
Use this command to update the Well Explorer tree to show any
additions, changes, and deletions. F5 will also refresh the Well
Explorer.
Expand All (Database Level)
This command expands all nodes below the selected level in the Well
Explorer tree.
Collapse All (Database Level)
This command collapses all nodes below the selected level in the Well
Explorer tree.
Working at the Company Level
In the Well Explorer, when you right click on a company, the right click
menu displays the following choices:
Command Description
Open Opens the selected item.
New Project Create a new project for the selected company (page 69).
New Attachment Displays the Attachment Properties dialog. (page 69)
Paste Paste copied company information from the Clipboard
(page 69).
Rename Activates the selected data item in the Tree, enabling you to
edit the name. (page 70)
Delete Delete the selected company and all associated child infor-
mation (page 70).
Export Export the selected company’s hierarchical information to
an XML file (page 70).
Search Choosing this option displays the Search dialog. (page 70)
Survey Tools Displays the Survey Tools dialog. (page 70)
Properties View or edit the selected company’s properties (page 70).
Expand All To expand all levels below the company level in the Well
Explorer. (page 89)
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Chapter 3: Using the Well Explorer
Open (Company Level)
Opens the selected company.
New Project (Company Level)
To create a new project, select a Company and right-click; select New
Project. The Project Properties dialog opens.
The fields and controls on the Project Properties dialog are explained in
detail on page 92.
New Attachment (Company Level)
Use this dialog to associate a document or picture (Word, Excel, text
file, JPG, etc.). Document can be of any type with a recognized
extension.
Paste (Company Level)
Use this command to paste (insert) the contents of the Clipboard at the
location currently selected in the Well Explorer.
Collapse All Collapses all levels below the company level in the Well
Explorer. (page 89)
Check the Save attachment as a link/shortcut only box if you want to save the attachment
as a link only. If you check this box, only the link to the disk file is stored in the database. Any
edits you make are saved to the original disk file. You can edit the document directly from the
Well Explorer, or you can edit the disk file from its disk location; the changes are reflected in
both places. In the Associated Data Viewer, the icon representing a Linked document is shown
as a paperclip with a small arrow in the lower left corner.
Use the Browse
button to navigate
to the location of
the file. If you
know the path,
you can enter it
without using the
Browse button.
Enter text that
provides detailed
descriptive
information about
this attachment.
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70 COMPASS Training Manual Landmark
In order for this function to be effective you must have Copied (saved)
company data to the Clipboard.
Rename (Company Level)
Use this command to rename the item. You can also rename the data
hierarchy item by highlighting it and the clicking once on it. Type the
new name in the box that appears around the current name.
Delete (Company Level)
Use this command to remove the selected Company from the database.
A confirmation box will open, asking if you are sure you want to delete
the company and all its associated data. Click Yes or No, as
appropriate.
Export (Company Level)
Use this command to export the selected Company’s data in XML
format. Includes any child information associated with the Company. A
dialog will open, allowing you to supply a directory and filename for
the XML file.
Search (Company Level)
Refer to “Search (Database Level)” on page 67 for information on using
the Search dialog.
Survey Tools (Company Level)
Displays the Survey Tools dialog. A survey tool is an instrument that is
used to measure the wellbore’s position using inclination and azimuth
measurements, followed by survey computation or by directly
integrating inertial positions.
Survey tools are used in COMPASS to describe the error characteristics
associated with the tool. The tool’s error characteristics are used to
calculate the magnitude of measurement uncertainty about the wellbore.
COMPASS enables you to define different survey tools with different
error models. Generally, every survey tool operated at one or more
different conditions should have an error model defined. The tools
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Chapter 3: Using the Well Explorer
should have logical names so they can be intuitively selected from the
Survey or Planning modules.
Survey Tool Error Models
A survey tool error model describes how wellpath positional uncertainty
is calculated. When you run Anti-collision, COMPASS uses the error
calculated around each wellpath based on the error model defined and
the survey tools used.
For a particular tool, you only need to enter parameters for the error
model selected. For example, if the model is error cone, you do not need
to enter error values for the Systematic Error, ISCWSA, or Inclination
Cone of Error Grid.
The three supported error models are:
� Cone of Error - For a range of inclinations, you may enter a
different error cone expansion rate.
Hide Survey
Tools that are no
longer used by
Company but
need for
historical
calculations.
Import enables
new survey tool
error models to be
imported from a
transfer file.List of Survey Tool
Names and
Descriptions.
Default Survey
Type defines the
survey
mechanism. This
is a useful feature
for filtering from a
large selection of
tools.
Assign a particular tool
to be the default.
Toggles enable
Tool Error Type to
be selected.
Delete unused Survey Tools
from Company List.
Save new tool or apply changes to
existing tool. This may update error
surfaces of wellpaths with definitive
paths using this tool.
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72 COMPASS Training Manual Landmark
� Systematic Error - Enter six coefficients for the survey instrument
components of error.
� ISCWSA - An extensible survey error modeling system with
configurable error terms and weighting functions.
You must assign a survey tool to the most appropriate error model with
accurate parameters. This information is most commonly provided by
the survey contractor. You should be able to email, phone, or fax any
survey contractor and request precise details of the error model for a
particular tool. Otherwise, you can find descriptions of many survey tool
error models on the Internet on websites for Sperry Sun, SDC, Anadrill,
etc.
In contrast, some operators (e.g. BPA, Shell) decide what the error
model and parameter values are for a tool. This assumes some form of
testing or statistical treatment of available survey data measured by that
tool.
Regardless of where the information is obtained, definition of a survey
tool error model is critical. A COMPASS anti-collision scan is only as
good as the survey tool error model itself.
Cone of Error
For a range of inclinations you can enter different error cone expansion
rates. The example below shows that from 15 to 35 degrees inclination
the cone of error expands at 5.0/1000ft (or 5m/1000m) of measured
depth.
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Chapter 3: Using the Well Explorer
The following depicts the Survey Tool Editor for a tool using the Cone
of Error model:
Systematic Error Ellipse
This is based on SPE paper 9223 by C.J.M. Wolff and J.P. de Wardt,
first published in the Journal of Petroleum Technology in December,
1981. The model is a statistical treatment of the distribution of errors
caused by internal and external influences. The paper demonstrates that
the major causes of error are systematic (that is, they happen
consistently in one vector direction) from one survey reading to the next.
There are error sources that are random, but they are assumed to be small
and tend to cancel out over a number of survey readings. The
mathematical methods applied by the paper have become industry
standard, but some of the example coefficient values and weightings are
not capable of modelling modern directional survey instruments (i.e.
MWD and Rate Gyroscopes).
Enter end of range for
the error term. Note:
grid starts at 0 deg.
Enter the expansion rate
per 1000 units.
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74 COMPASS Training Manual Landmark
The following depicts the Survey Tool Editor for a tool using the
Systematic Ellipse error model.
The Systematic Ellipse error model has six coefficients:
� Relative Depth Error - This is the amount of error in depth
reading per 1000 (ft or m) of measured depth. Depth error is
derived from pipe tally measurement and stretch for pipe run tools
and wireline measurement error for cable run tools.
� Misalignment Error - This is the error due to misalignment of the
survey tool in the borehole. Misalignment affects both inclination
and azimuth and is derived from sensor axis and tool centralizer
misalignment.
� True inclination error - Inclination error may be derived from
weight-induced effects on pipe running gear and is itself, sensitive
to inclination.
� Compass Reference Error - The error in referencing North. For
magnetic surveys this is the error in declination reading for the
locality. For gyro surveys this is the error in surface azimuth
orientation - foresight.
Six Wolff & de Wardt
Error Terms:
Inclination/Azimuth Error Grid. If
populated, overrides inclination and
azimuth errors.
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Chapter 3: Using the Well Explorer
� Drillstring Magnetization - Magnetization Error is the error in
magnetic azimuth readings caused by drillstring magnetization. The
error increases at higher inclinations and east / west azimuth.
� Gyrocompass Azimuth - The error in gimballed gyro azimuth
readings caused by gyro drift. Note that the Wolff & deWardt
weighting for this term is 1/cos(inclination). This means that the
derived error results will ‘explode’ at higher inclinations. The term
is meant to describe film read level rotor gyroscopes, that should
only be used at lower angles. Should you wish to describe a modern
rate/continuous gyro in the systematic error model, you need to use
the Inclination Azimuth error grid, which allows constant weighted
terms.
Because of the variation of error parameters along the X, Y, Z vectors,
the resultant shape of the error surface is an ellipse as projected in 2D,
an ellipsoid as plotted in 3D. The orientation of the ellipsoid with respect
to the wellpath is dependent on the relative change of Wellpath
Inclination and Azimuth.
The systematic error model coefficients and their weighting factors are
recognized as being inadequate for modern solid state magnetic
instruments and for rate gyroscopes. COMPASS provides the
inclination/azimuth error grid to help define error models for more
complex instruments. Again, the inclination and azimuth error
characteristics for each inclination angle range can be provided by the
manufacturers and inserted into the tables.
These error characteristics are substituted for the respective inclination
and azimuth error of the Wolff & de Wardt coefficients, therefore the
True Inclination Error, Drillstring Magnetization, and Gyrocompass
Azimuth coefficients are grayed-out. The inclination weighting factors
would not be applied, because of the relationship defined in the table.
The Interpolate toggle enables error values to be determined for
intermediate inclinations between the ranges entered.
ISCWSA
The Industry Steering Committee for Wellbore Survey Accuracy has
built a survey instrument error model specifically for solid state
magnetic instruments (e.g. MWD & EMS). The model is based on a
paper published by H.Williamson "Accuracy Prediction for Directional
MWD" as SPE56702. The model vastly extends the work started with
the systematic error model and incorporates the experience of the many
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76 COMPASS Training Manual Landmark
participating parties. COMPASS has extended the model by including a
format for defining error terms.
The error terms for this type of survey instrument should be entered in
the grid. The error value and weighting formula is be entered as well as
the vector direction and treatment at survey tie-on.
A row in the grid may be for an individual source of error that can be
from instrument reading, depth measurement, instrument barrel-
hole/collar alignment and external reference and interference terms.
The columns in the grid are as follows:
Name
Give the error source a unique name unless you want it added on to
the same source of error from another or the same tool. See Tie-on
definition to clarify what is in individual error term.Vector
This sets the vector direction for the error source. Select one from
the drop down list:
• A - Azimuth error (WdW).
• B - Azimuth bias
• D - Depth error (WdW)
• E - Depth error (ISCWSA)
• F - Depth bias (e.g. Wireline stretch outrun)
• I - Inclination error (highside)
Landmark COMPASS Training Manual 77
Chapter 3: Using the Well Explorer
• J - Inclination bias (uncorrected sag)
• L - Lateral error (error at 90/270 toolface equivalent to azimuth
error/sin(inclination))
• M - Misalignment – forms a disc about the wellpath.
• N - Inertial error – forms a sphere about the wellpath.
Value
The error value for the source of error: i.e. 1.0-degree reference.
Care must be specified to what confidence level and unit type for
the error value. The confidence level for the uncertainty is stated in
the Customer Properties. To get extra precision for this column
data, change the ‘Coefficient of Friction’ unit type in the Units
Editor.Tie-on
This determines how an error source is tied onto sources of the
same name from other tools. Select one from the drop down list:
• R - Random, error is added by RSS (Root Sum Squares) from
station to station.(e.g. Misalignment for rotating MWD)
• S - Systematic, error is added directly from station to station run
but added randomly at tie-on.
• W - Well, error is systematic throughout the well (e.g. Reference
error)
• G - Global, error is systematic across a number of wells. (E.g.
Crustal Declination error)
• N - Not used in error accumulation, (this term is used as an
intermediate calculation)
Units
The following unit selections are available, Select one from the
drop down list:
• N - No unit conversion.
• M – Meters to feet conversion, equivalent to MTF in the
formula.
• IM – Inverse feet to meters conversion, equivalent to 1/MTF in
the formula.
• D – Degrees to radians conversion equivalent to DTR in the
formula.
• T – Error per thousand feet. It is equivalent to a conversion of
0.001.
Other unit types may be given but are not interpreted.Formula
The formula is the weighting for each error term and is given as a
formula that can be parsed like Excel. Typical arithmetic
conventions can be used like: * / - +, power: X^Y,trigonometry:
Chapter 3: Using the Well Explorer
78 COMPASS Training Manual Landmark
SIN(), COS(), TAN(), ABS() etc. The capabilities of the parser are
better shown by the examples below.
The following names may be substituted in the formula:
• AZI - Azimuth of current station
• AZM - Azimuth from magnetic north (used for magnetic tools)
• AZT - Azimuth from true north (used for gyro tools)
• AZE - Azimuth error for tie on from previous tools (used to
determine reference error)
• INC - Inclination of current station
• TFO - Toolface angle - The instrument rotation (i.e. alignment of
Y accelerometer with highside)
• TMD - Measured depth from init point.
• TVD - Vertical depth from init point.
The program loads Magnetic Field Data:
• MTOT - Total magnetic field strength given in nanoTeslas (i.e.
50000). Note: Magnetometer bias errors must be same units
• DIP - Magnetic field dip angle from vertical.
• LAT - Current latitude.
• Gyro continuous values:
• AZE - Azimuth error before tie-on
• INX - Inclination error before tie-on
• DMD - Measured depth from start of this survey tool (i.e.
continuous mode drift terms)
• EROT - Earth’s rotation rate = DTR * 15.041 * Cos(Latitude)
• Gyro bias drift values should be entered in degrees/hour.
Constants:
• MTF - Meters to feet - the model evaluates in feet.
• DTR - Degrees to radians - use this when Error is given in
degrees
• GTOT - Gravity total (9.81 m/s^2)
• THO - Thousandths (=0.001)
Range
Check this box to specify an inclination range for this error term.
This term will only be included when the survey station inclination
is between the Min Inc and Max Inc – inclusive.
Example #1
# Model for Wolff &deWardt, Poor Magnetic. This example shows use
# of a bias error term MAGB.
#Name Vector Tie-On Value Formula
DEPTH D S 2 THO
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Chapter 3: Using the Well Explorer
MISAL M S 0.3 DTR
TINC I S 1 DTR*SIN(INC)
REF A S 1.5 DTR
MAGE A S 5 DTR*SIN(INC)*ABS(SIN(AZM))
MAGB B S 5 DTR*SIN(INC)*ABS(SIN(AZM))
Example #2
# Model for Gyro Continuous Tool (GCT)
# This model assumes changeover at 15 degrees
#Name Vector Tie-On Value Formula Min Inc Max Inc
DEPTH D S 2 THO
MISAL M R 0.1 DTR
TINC I S 0.06 DTR
ASFO I S 0.0016 ABS(TAN(INC-20*DTR))
# two reference errors one for each tool mode
REFA S 0.51DTR*COS(60*DTR)/COS(LAT) 0 14.999
REFA S 1.0 AZE 15 99.999
# two gyro bias errors one for each tool mode
GBLL S 0.8 DTR*DMD*TAN(INC)/4800 0 14.999
GBHL S 0.15 DTR*DMD/4800 15 99.999
To create a new tool:
1. Click the New button, to prepare the editor for a new survey tool.
2. Enter a unique name for this survey tool (you may use the same
name to identify the same tool in a different company).
3. If desired, you can enter a description of the tool.
4. Select the button next to the desired model type to enter the errors
you expect from this survey tool.
5. Click the Save button to add this tool to the list.
To edit an existing tool:
1. In the Survey Tools list, click on the tool you want to edit. This will
highlight the tool, and the Tool Properties will be displayed for the
selected tool.
2. Make the required changes.
3. Click the Save button to update the tool.
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80 COMPASS Training Manual Landmark
To delete a survey tool:
1. Click the tool you want to delete.
2. Click Delete. You can only delete tools that are not used by
COMPASS. If a tool you want to delete is used by any Definitive
Path, COMPASS displays a warning message that provides
instructions for removing any links to the tool defined in Surveys or
Plans. It can be difficult to locate all references for a tool.
To export a survey tool:
Export survey tools allows you to transfer tool data between companies
and systems.
1. Select a tool from the Survey Tools list by clicking on it.
2. Click the Export button.
3. Enter the filename to create. The default filename is Toolname.ipm
in the COMPASS/Output directory.
To import a survey tool:
Import Survey Tools allows you to have a common set of tools sites
within a company.
1. Make sure you don't have a tool selected in the Survey Tools list.
2. Click the Import button.
3. Enter the directory and select the filename to import. These file
names should have an extension of .IPM.
Note: Using the Save Button
Once the Save button is clicked you may see a message box with "A number of
Wellbores use this tool…Do you want to rebuild them now?". Choosing Yes will
rebuild the definitive surveys with the new error data. The update process can take
some time.
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Chapter 3: Using the Well Explorer
Properties (Company Level)
Selecting this command allows you to view or edit Company
properties. The Company Properties dialog opens. The Company
Properties dialog is used to create a new company and to provide
information regarding creation and modification of the company. In
COMPASS, the Company controls policy and settings for a number of
operating projects or sites. The Company is either an operating group
within your exploration company or for a contractor it is the operating
company for which the services are provided. The company unit should
have common directional drilling operating practices and policies. The
Company Properties tabs are used to specify the specific survey and
anti-collision policy for the group.
Using the Company Properties > General Tab
A Company Logo can be
selected to appear consistently
in Reports and Wallplots
A Company Level
password enables
settings to be
applied
consistently within
an organization.
Locked Data
passwords enable
Field, Sites, Wells
and Wellpaths to
be locked to
prevent changes.
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Using the Company Properties > Anticollision Tab
Survey Error Model
Error System
Use the drop-down list to select the error system. The options are:
ISCWSA and Cone of Error. For more information about the
ISCWA Survey Error Model, see “ISCWSA” on page 75. Output Errors are at_sigma
Enter a numeric value. This value states the confidence level for the
survey errors in number of standard deviations. The errors defined
in the survey instrument error models have to be defined at a known
standard. Error terms are expressed in standard deviations from the
mean (or sigma). One standard deviation implies that roughly 65%
of readings will be within the stated error. Two standard deviations
require that 95% of readings will be within the stated error.
Confidence levels are required to make risk based decisions on
collision and target intercept calculations.
Anticollision Settings
Scan Method
When selecting a scan method you define how wellbore separation
is computed. There are a number of different methods for
computing the distance from the current wellbore to other wells.
Four Scan Methods are available in COMPASS, including:
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Chapter 3: Using the Well Explorer
• Closest Approach 3D: At each MD interval on the reference
wellpath, COMPASS computes the distance to the closest point
on the offset wellpath. At the scan depth on our reference
wellpath, imagine an expanding bubble or spheroid. The
minimum distance occurs when the surface of the spheroid just
touches the offset wellpath. Because the offset wellpath is now
at a tangent to our spherical bubble, the line of closest approach
is perpendicular to our offset wellpath.
The following graphic depicts the 3D Closest Approach Scan
Method (left), and the traveling Cylinder method (right):
• Traveling Cylinder: This scan method uses a plane
perpendicular to the reference wellpath and intercepting offset
wellpaths as they cut through the plane. The surface resembles a
cylinder with the size of the maximum scan radius. The traveling
cylinder method computes distance from the offset wellpath
stations back to the reference wellpath. The benefit of this
method is that intercepts are detected even when the wellpaths
are approaching at a perpendicular. In this case, there may be
more than one point in the TC plane for the same depth on the
reference. Depths are interpolated on the offset wellpaths,
resulting in irregular depths on the reference wellpath.
Therefore, the 3D anticollision view and traveling cylinders
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84 COMPASS Training Manual Landmark
depth slice option are not possible with this method, because
they rely on regular depths on the reference.
• Horizontal Plane: This method is the horizontal distance from
the reference wellpath to the offset wellpath.
The following graphic depicts the Horizontal Scan Method:
• Trav Cylinder North: This scan method uses the same
perpendicular plane as the traveling Cylinder scan method, but
toolface orientation from reference to offset is added to current
Wellbore direction. The traveling cylinder plot is oriented to
Map North when the reference well is at low angles. Toolface
angle to an offset well is then reported as the angle from the
high-side of your current Wellbore + the azimuth of your current
Wellbore. This method avoids the confusion in the traveling
Cylinders plot caused by large changes in toolface angle when
kicking-off from vertical.
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Error Surface
When selecting an error surface you define the shape of the
uncertainty envelope about the wellbore. The error surface choice
allows the user to override the standard ellipse to ellipse (default)
ratio calculations in anti-collision, and instead uses the largest
dimension of error at a point to define a cone about the Wellbore. In
most cases, this will be major axis of the ellipsoid. Using the
circular conic method is more conservative and produces lower
ratio values and hence more warnings. The choices are as follows:
• Elliptical Conic: The elliptical method interpolates the error
surface in each wellbore by assuming the surface is an ellipse
with major and minor axis perpendicular to the Wellbore.
Because the center to center plane can intersect the error
ellipsoid at any direction from the Wellbore, the resulting radius
used in the separation factor calculation ranges from the
minimum dimension of the ellipse (minor axis) to a maximum
dimension (major axis). The ellipse also has an intermediate axis
with a magnitude somewhere between the minor and major axis
dimensions.
• Circular Conic: The circular conic method uses the largest
dimension (major axis) of the error ellipsoid at a point to define
a spheroid about the Wellbore. Projected down the Wellbore, this
becomes a cone. Using the circular conic method is always most
conservative because it uses the largest dimension of the ellipse
and therefore produces lower ratio values and hence more
warnings.
• Combined Covariance: This method combines the errors on
the reference and offset by covariance addition before any
distance calculations are performed. The error distance is then
computed by the ‘elliptical conic’ method on the resulting single
ellipsoid. Where Casings are included the radii are subtracted
from the center- to - center distance. The separation factor
derived from the combined covariance technique can be directly
correlated to collision risk as it represents the standard deviation
value for the ‘tail of the probability distribution’.
Casings
Choose one of three options:
• No - Casing diameters are not applied.
• Add - Casing diameters are added to the error ellipse
dimensions. The calculation is:
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Separation Factor Ratio = Center to Center Distance /
(Reference Error Radius + Offset Error Radius + Offset
Casing Radius + Reference Hole Radius)
• Subtract - Casing diameters are subtracted from the center-to-
center distance. The calculation is:
Separation Factor Ratio = (Center-to-Center Distance -
Offset Casing Radius - Reference Hole Radius) / (Reference
Error Radius + Offset Error Radius)
Warning Type
There are a number of methods for warning the user of potential
collision problems. The choice made here will decide how the
Anticollision Warning Levels are used. The options are:
• Error Ratio - The warning given will depend on the ratio of the
separation distance divided by the combined error radii of the
reference and offset wells at a given depth.
• Depth Ratio - The warning given will depend on the ratio of the
separation distance divided by the depth times a ratio (i.e.
10/1000 MD) Error values may be added to this cone.
• Rules Based - In this case each offset Wellbore is assigned with
a rule. A warning is given if the rule is failed.
Warning Levels or Rules
This grid is used to define a number of anticollision warning criteria.
The columns and labels that appear on this dialog depend on which
Warning Type is chosen in the Anticollision Settings section of the
Company Properties dialog. The Warning Type determines the
appearance of this grid. Refer to this table for details. Refer to the online
help for specific information on using this grid.
Note: Using the Subtract option...
Be aware that using the Subtract option, it is possible to have a Center-to-Center
distance that is negative in top-hole.
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Using the Company Properties > Calc Defaults Tab
Survey Calculation Method
COMPASS offers four survey calculation methods.
• Minimum Curvature
• Radius of Curvature
• Average Angle
• Balanced Tangential
V Section Origin
The default vertical section may start from either slot or from
platform center as shown here. The default vertical section origin
may be overridden in the Wellbore Setup dialog.Walk/ Turn Rate
There are two methods for computing walk and turn rates for curve
sections
• MD - Turn rate = dogleg base length x change in direction /
change in measured depth (default)
Note: Survey Calculation Method
This setting specified on the Company Properties dialog is the company's preferred calculation method and may not be overridden in the survey module.
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• HDL - Turn rate = dogleg base length x change in direction x
sine( (I1 + I2) / 2 ) / change measured depth where I1 is the start
inclination I2 is the end inclination.
Validation
• Project – Select a project for the validation process, or select
‘all’ to choose all projects for this customer.
• Create Well Co-ordinates File – Click this button to report all
wells surface and bottomhole co-ordinates to a file in the config
directory called ‘WellCoordinates.log’. This file can be used to
validate the Compass database before and after any significant
data changes.
• Compute all Designs - Click this button to start the re-
calculation of all wellpaths, plans and surveys. When a value is
changed in Company Properties, the wellpath data may not be
built according to the rules in the survey program or the survey
error model. The validation process is provided to re-calculate
all wellpaths using the correct program and survey errors. In the
re-calculate step two files are created in the output directory,
these list the surface and end of well co-ordinates before and
after re-processing and lists any associated errors.
Using the Company Properties > Wellbore Types Tab
A Wellbore type is a set of Wellbore labels or type names. Each
Company can have a range of different Wellbore types and each type
can have a designated color to identify Wellbore groups in plots. Once
the Wellbore type list is created, a Wellbore type may be assigned to a
Wellbore in Wellbore Properties > General tab. Wellbores may then
be selected for plots and anticollision scans based on the type.
Some Examples of Wellbore Types:
� Producing Well - Red
� Injection Well - Blue
� Abandoned Hole - Yellow
� Lateral Wellbore - Green
� Fish (abandoned)
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� Pilot Hole
Expand All (Company Level)
Select this command to expand all nodes in the Well Explorer below
the selected Company.
Collapse All (Company Level)
Select this command to collapse all nodes in the Well Explorer below
the selected Company.
Working at the Project Level
Project is the data level directly beneath company and each project
within a company must have a unique name. A project can be thought
of as a field or as a group of sites. A project has one system datum
(mean sea level, lowest astronomical tide, etc.) that is used to define 0
TVD for the project. Within the project, wellbores can be referenced to
the project level system datum or to additional datums specified at the
well level.
In the Well Explorer, when you right click on a project, the right click
menu displays the following choices:
Command Description
Open Open selected project.
New Site Create a new site for the selected project (page 90).
Click on the color column
and a palette of colors will be
displayed to choose from.
Type the name.
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Open (Project Level)
Opens the selected project.
New Site (Project Level)
To create a new site, select a project and right-click; select New Site.
The Site Properties dialog opens.The fields and controls on the Site
Properties dialog are explained in detail on page 104.
New Attachment (Project Level)
Use this dialog to associate a document or picture (Word, Excel, text
file, JPG, etc.). The document can be of any type with a recognized
extension. Refer to “New Attachment (Company Level)” on page 69
for more information.
New Attachment Displays the Attachment Properties dialog. Refer to “New
Attachment (Company Level)” on page 69 for more information.
Copy Copy the selected project data to the Clipboard (page 91).
Paste Paste copied project information (page 91).
Rename Activates the selected data item in the Tree, enabling you to edit
the name. (page 91)
Delete Delete the selected project and all associated child information
(page 91).
Export Export the selected project’s hierarchical information to an XML
file (page 91).
Search Choosing this option displays the Search dialog. Refer to
“Search (Company Level)” on page 70 for more information.
Targets Accesses the Target Editor. Use the Target Editor to define target
location and shape. (page 91)
Lease Lines A lease line is a United States convention for limiting drilling
territories. Use this dialog to create and maintain lease lines.
(page 92)
Properties View or edit the project properties (page 92).
Expand All To expand all levels below the project level in the Well Explorer
(page 96).
Collapse All To collapse all levels below the project level in the Well
Explorer. (page 96)
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Copy (Project Level)
Use this command to copy the selected project from the Well Explorer
and save it to the Clipboard.
This command is disabled if nothing has been selected.
Paste (Project Level)
Use this command to paste (insert) the contents of the Clipboard at the
location currently selected in the Well Explorer.
In order for this function to be effective you must have Copied (saved)
project data to the Clipboard.
Rename (Project Level)
Use this command to rename the item. You can also rename the data
hierarchy item by highlighting it and the clicking once on it. Type the
new name in the box that appears around the current name.
Delete (Project Level)
Use this command to remove the selected project from the database. A
confirmation box will open, asking if you are sure you want to delete
the project and all its associated data. Click Yes or No, as appropriate.
Export (Project Level)
Use this command to export the selected Project’s data in XML format.
Includes the hierarchical information above and any child information
associated with the Project. A dialog will open, allowing you to supply
a directory and filename for the XML file.
Search (Project Level)
Refer to “Search (Database Level)” on page 67 for information on using
the Search dialog.
Targets (Project Level)
Use this command to access the Target Editor. A target is a point in a
geological space that is used as an aiming point or volume for directing
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Wellbores Use the Target Editor to define target location and shape. The
form is also used for managing several targets on a Wellbore or a site.
Refer to “Defining Targets” on page 150 for more information.
Lease Lines (Project Level)
Properties (Project Level)
Selecting this command allows you to view or edit Project properties.
The Project Properties tabs are used to create a new project and to
provide information regarding creation and modification of the project.
Note: If there is no local origin in effect...
If no local origin is in effect, the Coord Type, N/S, E/W, Direction and Distance
columns will not be visible.
This area displays the
existing lease lines in
COMPASS. Select a lease
line to display and edit the
associated data.
Enter the name if you are creating a
new lease line. If you are viewing or
editing an existing lease line, the
name appears in this field when you
select the lease line in the Lease
Line Name area.
Select this checkbox to make the lease
line visible in graphs and plots
Use the pull-down menu to
select how the location of
the point will be defined and
type the required
information.
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Using the Project Properties > General Tab
System Datum
Define the common vertical reference for all depth measurements
in this Project. Select a name from the list or type in a new name.
Examples are "Mean Sea Level", "Lowest Astronomic Tide",
"Indian Springs Low".Elevation__ft above Mean Sea Level
Enter the elevation above Mean Sea Level for the System Datum
you selected. Enter a negative value if the elevation is below Mean
Sea Level.Use Well Reference Point
When this box is checked, you can enter a Well Reference Point in
the Well Properties Dialog. A Well Reference Point is a permanent,
recoverable, fixed point in the well and may be used as the tie-in
point for the first survey and plan on this well.Default Magnetic Model
Use the pull-down menu to select a default magnetic model.
Refer to “Using Datums in EDM”
on page 50 for more information
on datums.
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Using the Project Properties > Map Info Tab
Geographic Reference System
You must select the correct geodetic system before computing grid
convergence or performing geodetic conversions (latitude & longitude
to easting & northing and vice versa).
Three choices need to be made:
• Geodetic System - The general mapping system, e.g. "Universal
Transverse Mercator". You can use the pull-down menu to
change the project’s geodetic system. Doing so converts all map
and global coordinates from the old system to the new system
using one of two options:
• Convert and preserve map coordinates
• Convert and preserve lat/long.
COMPASS will prompt you for the conversion method, which
will convert data stored in the database in addition to the
onscreen data.
• Geodetic Datum - The datum defines the center and radii of the
projection in this location, e.g. "ED50".
• Map Zone - The zone within the system, e.g. "UTM Zone 31,
North 0 to 6 E"
For more information see “Geodesy” on page 368.
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Local Co-ordinate System
The local co-ordinate origin is the zero point for north and east co-
ordinates. The choices are as follows:
• Originates From Well Center – The convention is to use the
rig-floor center position of the current well as the common
reference for all wells relative to it.
• Originates From Site Center – This convention uses a common
point in the template or installation as a common reference.
• Originates From Project Center Based On Site – This
convention is to use a single point within (or without) the Project
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as a common reference for all wells. In Compass, you must
create a single site as the center for the Project co-ordinates.
Use Geodetic Scale Factor (local co-ordinates are true distances)
When converting from distances on a map to distances measured on
the ground there is a small difference caused by the curvature in the
earth. A map system is designed to minimize this distortion. In a
UTM system, the difference will be 4m over a 10,000m east/west
traverse at the central meridian. Without this option, land distances
may be converted directly to map distances (provided meters to feet
and true north convergence rotations are calculated). With this
option, a scale factor is applied. The value for a location may be
seen in the Geodetic Calculator.
Expand All (Project Level)
Select this command to expand all nodes in the Well Explorer below
the selected Project.
Collapse All (Project Level)
Select this command to collapse all nodes in the Well Explorer below
the selected Project.
Working at the Site Level
A Site is a collection of one or more Wells all referenced from a local
coordinate system centered on the site location. A site can be a single
land well, an offshore sub-sea well, a group of wells drilled from an
Note: Project Centered Co-Ordinate Systems
Because each site has a different convergence angle, if you choose a Project
Centred co-ordinate system, local north must be based on the map Grid.
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onshore pad, or a group of wells drilled from an offshore platform or
template.
In the Well Explorer, when you right click on a site, the right click
menu displays the following choices
Open (Site Level)
Open the current site.
Command Description
Open Open the current site.
New Well Create a new well for the selected site (page 98).
New Attachment Displays the Attachment Properties dialog. Refer to “New
Attachment (Company Level)” on page 69 for more information.
Copy Copy the selected site data to the Clipboard (page 98).
Paste Paste copied site information (page 98).
Rename Activates the selected data item in the Tree, enabling you to edit
the name. (page 98)
Delete Delete the selected site and all associated child information
(page 98).
Export Export the selected site’s hierarchical information to an XML
file (page 99).
Search Choosing this option displays the Search dialog. Refer to
“Search (Company Level)” on page 70 for more information.
Unlock All Unlocks all the data in this site. (page 99)
Templates Use to access the Template Editor. A template is a surface or sea-
bed structure that frames a number of wellheads together with a
regular spacing. The Template Editor is a quick way of calculat-
ing the local co-ordinates of a template array. (page 99)
Properties View or edit the site properties (page 104).
Expand All To expand all levels below the site level in the Well Explorer
(page 107).
Collapse All To collapse all levels below the site level in the Well Explorer.
(page 107)
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New Well (Site Level)
To create a new well, select a site and right-click; select New Well. The
Well Properties dialog opens. If you want to “lock” the data and
prevent changes to the well data and all levels below it, set the Locked
Data password in the Company Properties dialog box. Toggle on “Well
is locked:” in the Well Properties dialog after setting the password.
Click OK.
The fields and controls on the Well Properties dialog are explained in
detail on page 111.
New Attachment (Site Level)
Use this dialog to associate a document or picture (Word, Excel, text
file, JPG, etc.). The document can be of any type with a recognized
extension. Refer to “New Attachment (Company Level)” on page 69
for more information.
Copy (Site Level)
Use this command to copy the selected site from the Well Explorer and
save it to the Clipboard.
Paste (Site Level)
Use this command to paste (insert) the contents of the Clipboard at the
location currently selected in the Well Explorer.
In order for this function to be effective you must have Copied (saved)
site data to the Clipboard.
Rename (Site Level)
Use this command to rename the item. You can also rename the data
hierarchy item by highlighting it and the clicking once on it. Type the
new name in the box that appears around the current name.
Delete (Site Level)
Use this command to remove the selected site from the database. A
confirmation box will open, asking if you are sure you want to delete
the site and all its associated data. Click Yes or No, as appropriate.
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Export (Site Level)
Use this command to export the selected Site’s data in XML format.
Includes the hierarchical information above and any child information
associated with the Site. A dialog will open, allowing you to supply a
directory and filename for the XML file.
Search (Site Level)
Refer to “Search (Database Level)” on page 67 for information on using
the Search dialog.
Unlock (Site Level)
Use this option to unlock all data associated with this site.
Templates (Site Level)
Use this command to access the Template Editor. A template is an array
of slot coordinates that define the surface/subsea location of wells. The
Site Template Editor is a coordinate generator that provides an easy way
to define slot template geometries. When you define a template, you can
enter single slot coordinates, or, if the template has a rectangular or
circular slot layout, COMPASS can automatically calculate the local
slot coordinates for you.
A site can have more than one template defined for it—for example, a
collection of sub-sea wells or a platform that has had additional slots
attached to it.
Template Editor
When creating a well, you don’t have to use the Site Template Editor to
define the well location. You can type in the local coordinates directly.
However, if slots are defined, you can select a start slot and assume the
calculated local coordinates of that slot.
The Template Editor uses two resizeable panes located in the same
Window: an Editor and a View. The relative sizes of each may be
adjusted by moving the separator bar. The Editor enables you to define
templates.The View graphically portrays the template currently
selected, and provides the usual COMPASS live graphics tools.The
following graphic depicts the Slot Template Editor and View:
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The Template Editor consists of 2 panels.
� The left panel is the Editor Panel and is used to enter name and
numeric data. The Editor Panel has two tabs, including the Slots
tab, and the Geometry tab.
� The right panel is the Template View. It can be used to select
templates and individual slots. The currently selected slot is
highlighted in red. The other slots are in green.
The editor panel may be toggled between viewing the entered template
patterns or a list of each individual slot generated by all the patterns.
COMPASS supports three types of Templates:
Template Type Definition
Rectangular Row by Column slot spacing
Circular Radial slot spacing
Single One slot, such as sub-sea well or onshore
drilling pad
Define template properties here.
View/Select Templates Here
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You can convert regular shaped rectangular and circular templates to
single slot templates if required. Note: this is not reversible.
For each type of template, you must enter a short name, a long name, and
the location of slot reference from the site center. If Site is a platform
then coordinates are normally 0 NS, 0 EW. In the example above, the
Echo template has a short name E so that each slot is numbered E1, E2,
E3, and so on. You define the template geometry and then add it using
the Add button in the toolbar, modify it using the Save button, or delete
it using the Delete button. Existing templates may be selected from the
picklist on the Geometry tab or selected using the mouse within the
View. Active templates are highlighted in red within the View.
After generating one or more templates, you use the View Slots tab
available near the bottom left of the editor to display the local
coordinates of all slots in the site. You cannot edit slots or templates
with the View Slots toggle set, you must toggle back to the Geometry
tab. The View Slots tab does enable a group of single slot templates to
be rotated by a given angle about a rotation point. This would be used
where a rectangular or circular template had not been used to define slot
spacings, but the slots needed to be rotated.l
Rectangular Template
Start Number
Start numbering slots from this number. For example, if your site
has two templates, each with 9 slots, you may want to start
numbering the first template from 1 and the second from 10.Numbering
Slot numbers can be ordered by row or column as shown below.
Note: Curved Conductors
If curved conductors are defined in Well Setup, then you will see additional blue slots in the View to indicate different location of Well Reference Point relative to Slot (red).
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The following graphic depicts Rectangular Template Slot Numbering:
Slot Geometry
Rectangular templates are defined with a number of spaced rows and
columns with their own regular spacings.
The top left slot is used to determine the location of the Template
Center. The location of the top left slot is entered as X & Y offsets from
the template center without considering rotation.
The following graphic depicts Rectangular Template Geometry:
Template
Center
2m
2m
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In the above example there are 3 rows and 5 columns. The template short
name is ‘R’. The row spacing is 2m, and the column spacing 2m. The Y
distance to the top left slot is 2m, and the X distance is -4m. With the
rotation angle set to 45 degrees, our final template appears as above.
Circular Template
Start number
Start numbering slots from this number. For example, if your site
has two templates each of 16 slots, you may want to start
numbering the first template from 1 and the second from 17.With Numbering Clockwise
Slot numbers can be ordered clockwise or counter-clockwise.Radius to first slot
Enter the radius of the circular template.Number of slots
Enter the number of slots on the template. These are evenly
distributed about the circle, starting at the angle to the first slot.Angle to first slot
The direction from local north to the first slot.
The following graphic depicts Circular Template Geometry:
This template example has 8 slots. The template short name is C. The
start number is 1, numbered clockwise. The radius is 4m, and the angle
to the first slot is 22.5 degrees.
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Properties (Site Level)
Selecting this command allows you to view or edit Site properties. The
Site Properties dialog opens.
Using the Site Properties > General Tab
The Site Properties dialog is used to create a new site and to provide
information regarding creation and modification of the site.:
This is the security designation for this Site,
based on the current user’s access rights.
UNRESTRICTED is the default. Be careful -
if you restrict this field, certain users will not
be able to view this Site. Tight groups are
created in the EDM Administration Utility
through the EDM Security plug-in. They are
assigned in the Well Explorer at the site or
well level.
Enter the numeric value for
the default site elevation.
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Using the Site Properties > Location Tab
Center Location
COMPASS uses the Map Coordinates values to compute the distance
between two sites during field level anti-collision. You can enter Map
Coordinates directly or convert them from latitude and longitude.
Choice Description
None If selected, anti-collision between sites is
disabled
Map Coordinates The map coordinates of your location based
on the Geodetic System selected in the Project
Properties dialog. These are essential if you
compute project level anti-collision. The map
coordinate units are set in the Unit System.
Geographic Coordinates The geodetic co-ordinates of your location
based on the geodetic datum selected in
Project Properties. To enter geographic co-
ordinates, you must first select a geodetic
system in Project Properties.
Lease Lines Enter a distance from one corner of the lease.
Positive numbers are interpreted as from the
south and west lines. Negative numbers are
interpreted as from the north and east lines.
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The graphic below depicts Lease Line coordinates. Two site centers are
indicated, one as a distance from a West and North line, another from an
East and South line:
Location Uncertainty
Radius of Uncertainty
This is the accuracy to which the site has been positioned or
uncertainty of the local co-ordinate origin relative to map or
geodetic co-ordinates.
For example, a floating drilling rig may be positioned with accuracy
of 1-2 m and due to wind and wave movement oscillates around the
mean position. When spudding an exploration well, this uncertainty
should be included, as it will be used during anticollision
calculations between wells drilled from different sites.
If drilling over a sub-sea template, you should include the position
uncertainty of the template, not that of the vessel. The unit class is
Note: Anti-Collision Requires Map Co-Ordinates
COMPASS does not use lease line co-ordinates to compute anticollision between
two sites. Anticollision requires map co-ordinates.
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Distance and uses the same units as your local co-ordinate system,
not the Map Units.
Slot Radius
This is the radius of the slots in the template view. This field may
also be used as the radius of the drill bit for the first hole section.
For cone of error models, this radius is added to all errors calculated
for the Wellbores included in this site. Example: A drill bit of 26"
diameter has a radius of 1.1'.
Azimuth Reference
North Reference
You may align the site's local co-ordinate system to either True or
Grid north. Depending upon your selection, the north axis of all the
sites in the Project will be aligned to either true or grid north and all
surveys should be corrected accordingly. In a True North system the
azimuths and co-ordinates will be rotated by the convergence angle
from the grid lines on the map. For more information, refer to
“True, Grid, and Magnetic North” on page 377.Convergence Angle
This non-editable field is the difference between grid north and true
north. This angle correction is only applied in the opposite sense to
azimuths when using a Grid North reference. Convergence is used
when computing anticollision between sites when using a True
North co-ordinate system.
Expand All (Site Level)
Select this command to expand all nodes in the Well Explorer below
the selected Site.
Collapse All (Site Level)
Select this command to collapse all nodes in the Well Explorer below
the selected Site.
Note: COMPASS uses the ISCWSA survey error framework...
Compass now uses the ISCWSA survey error framework for calculating all survey
errors and requires that all instrument & location error input is to 1 sigma
confidence. This means that the Site and Well location errors are now 0.5 the value
entered in previous versions of Compass where the Company error model was
Systematic or Cone of Error. The only exception is that Compass allows survey
instrument errors to be entered in the Systematic or Cone of Error formats as
before.
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Working at the Well Level
A Well is simply a surface location, referenced from the Site local
coordinate system. A well can be located at the site center or offset some
distance N/S - E/W from the site center. If a geodetic system is
configured for the Project, equivalent Map Coordinates are calculated
automatically. If a template has been created for the Site, a Well can be
assigned to a slot in that template. In the latter case, the well location
assumes that of the slot. For Land wells, a Site and a Well are often the
same thing. So, local coordinates from the Site for the Well are set to
0 N/S, 0 E/W, with the names being identical.
A Well can have one or more Wellbores assigned to it. For example, the
original wellbore, with one or more sidetracks tied on to it at different
kick-off depths. In COMPASS, any wellpath trajectory can be traced
directly from its TD back to the Well surface location.
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In the Well Explorer, when you right click on a well, the right click
menu displays the following choices
Open (Well Level)
Open the selected well.
New Wellbore (Well Level)
To create a new wellbore, select a well and click New Wellbore. The
Wellbore Properties dialog opens.
The fields and controls on the Wellbore Properties dialog are explained
in detail on page 118.
Command Description
Open Open the selected well.
New Wellbore Create a new wellbore for the selected well (page 109).
New Attachment Displays the Attachment Properties dialog. Refer to “New
Attachment (Company Level)” on page 69 for more information.
Copy Copy the selected well data, and all associated data, to the
Clipboard (page 110).
Paste Paste copied well information, including all associated data
(page 110).
Rename Activates the selected data item in the Tree, enabling you to edit
the name. (page 110)
Delete Delete the selected well and all associated child information
(page 110).
Export Export the selected well hierarchical information to an XML file
(page 110).
Search Choosing this option displays the Search dialog. Refer to
“Search (Company Level)” on page 70 for more information.
Properties View or edit the well properties (page 111).
Expand All To expand all levels below the well level in the Well Explorer
(page 115).
Collapse All To collapse all levels below the project level in the Well
Explorer. (page 115)
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New Attachment (Well Level)
Use this dialog to associate a document or picture (Word, Excel, text
file, JPG, etc.). The document can be of any type with a recognized
extension. Refer to “New Attachment (Company Level)” on page 69
for more information.
Copy (Well Level)
Use this command to copy the selected well from the Well Explorer and
save it to the Clipboard.
Paste (Well Level)
Use this command to paste (insert) the contents of the Clipboard at the
location currently selected in the Well Explorer.
In order for this function to be effective you must have Copied (saved)
well data to the Clipboard.
Rename (Well Level)
Use this command to rename the item. You can also rename the data
hierarchy item by highlighting it and the clicking once on it. Type the
new name in the box that appears around the current name.
Delete (Well Level)
Use this command to remove the selected well from the database. A
confirmation box will open, asking if you are sure you want to delete
the well and all its associated data. Click Yes or No, as appropriate.
Export (Well Level)
Use this command to export the selected Well’s data in XML format.
Includes the hierarchical information above and any child information
associated with the Well. A dialog will open, allowing you to supply a
directory and filename for the XML file.
Search (Well Level)
Refer to “Search (Database Level)” on page 67 for information on
using the Search dialog.
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Properties (Well Level)
Selecting this command allows you to view or edit Well properties. The
Well Properties dialog opens. The Well Properties dialog is used to
create a new well and to provide information regarding creation and
modification of the well. A well in COMPASS is a surface hole or
wellhead through which a number of Wellbores are drilled. The Well
Properties dialog is used to enter the well's offset location from the site,
plus naming information. Under each well you may define several
Wellbores.
Using the Well Properties > General Tab
Using the Well Properties > Depth Reference Tab
Use the Well Properties > Depth Reference tab to define depth
reference datums relative to the system datum specified on the Project
Note: If the “Well is locked” box is checked.
If the box is checked, you will not be able to edit any of the fields.
This is the default display unit system for the well. When a well
is opened (or one of it's wellbores or designs), the display unit
system will automatically change to the well display unit
system.
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Properties > General tab. Refer to “Using Datums in EDM” on
page 50 for more information about datums.
Refer to “Using Datums in EDM” on page 50 for more information
about datums.
Using the Well Properties > Well Ref Pt Tab
The WRP is a permanent, recoverable, fixed point in the well. This point
is usually at the well's position at seabed for offshore installations or at
ground level for land installations. This location will be used as the tie-
in point for the first survey and plan on this well. This tab appears when
Use the grid to view, edit, or add a
new datum. Check the Default box
to indicate which datum is the datum
to be used for all designs created for
this well.
Type, edit, or view the elevation above the System
Datum (this must be a positive number). If you
have a design associated with this datum, you
cannot edit this field.
Refer to the online help for
details on specifying
configuration.
The summary area depicts the selected
configuration.
The label indicates what
the system datum is.
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the vertical system in the Project Properties has been set to well
reference point (WRP).
Vertical Distance Above/Below System
Enter the vertical distance of the point above or below the system
datum. For offshore installations the distance is positive below
mean sea level. For land installations the distance is positive above
mean sea level.Non Vertical (curved conductor/slant rig)
If the rig is vertically positioned above the wellhead then all you
need to enter is the vertical distance above /below system. If the rig
is offset from the wellhead for various reasons, you need to enter
the information below to define the offset location of the well
reference point.Additional Measured Depth at WRP
If the wellbore is non-vertical at the WRP then the along hole
distance from rig datum to WRP is longer than the vertical distance.
In this case, enter the additional measured depth, which is usually
less than 1m for curved conductors. This additional distance will
not change if the rig elevation change.Offset from Wellhead North/East
Enter the horizontal distance from the wellhead (on fixed
installation) to the WRP on the seabed/ground. Inclination and Azimuth
Enter the wellbore inclination and direction at WRP, if it is non-
vertical. Azimuth is to the north reference (True or Grid) chosen in
Site Properties.
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Using the Well Properties > Location Tab
There is a choice of several methods for defining a wellhead location
relative to the site.
Slot
Select a slot from the list you have defined in the Template Editor.
If this slot is subsequently moved in the Template Editor then the
wellhead and all data will move accordingly.Offset from Site
Enter the offset distance, N/S and E/W from site center to this
wellhead.Map
The wellhead position may be defined in map co-ordinates. Enter
the Easting or Northing of the wellhead and the local co-ordinates
will be calculated from the site center. The well location is stored
relative to the site, so if the site moves, the well will move too.Geographic
You can check this option and enter latitude and longitude
coordinates to indicate the location of the wellhead.Well Position Error
A position error may be associated with the well location. This
error is added to all errors generated on Wellbores in this well. Be
careful not to confuse this error with site position error. The well
error is designed for special cases. For example, when there are a
number of wellheads in close proximity to each other (grouped in
the same site) but not connected by a template. The well error in
this case is the error in measurement of one well relative to the
others, but not the error in the group’s location, which is the site
position error. It is recommended that well error be left as zero for
template wells.
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Convergence
This non-editable field is the difference between grid north and true
north. This angle correction is only applied in the opposite sense to
azimuths when using a Grid North reference. Convergence is used
when computing anticollision between sites when using a True
North co-ordinate system.
Expand All (Well Level)
Select this command to expand all nodes in the Well Explorer below
the selected Well.
Collapse All (Well Level)
Select this command to collapse all nodes in the Well Explorer below
the selected Project.
Working at the Wellbore Level
A Welbore is a borehole, which is one or more contiguous sections of
wellbore traceable up to the surface location. It could be an original well
drilled from surface, or a sidetrack kicked off from a known depth from
a parent wellpath. If a Well has an original hole and two sidetracks
drilled from it, that Well has three Wellbores defined in COMPASS.
When using COMPASS there is only one active wellpath whose name
appears in the Status window. The Wellbore category allows you to file
multiple Surveys and Plans in their respective boreholes. When opening
Surveys or Plans, you are only shown names of items in the current
wellpath.
A Wellbore describes the path of a well that may be planned (or
unplanned) sidetrack or a lateral in a multi-lateral completion. The
original hole must also be represented as a Wellbore. In this dialog the
Wellbore name, and sidetrack information must be defined. In addition
a Wellbore may be drilled from a different rig datum elevation.
In the Well Explorer, when you right click on a wellbore, the right click
menu displays the following choices:
Command Description
Open Open the selected wellbore.
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Open (Wellbore Level)
Use to open the selected wellbore.
New Plan (Wellbore Level)
Use this command to access the Plan Properties dialog to define the plan
name, contractor, survey tool and tie-on information for this directional
survey. Refer to “Using the Plan Editor” on page 164 for more
information.
New Actual Design (Wellbore Level)
To create a new actual design, select a wellbore and right-click; select
New Actual Design. The Design Properties dialog opens.
The fields and controls on the Actual Design Properties dialog are
explained in detail on page 124.
New Plan Access the Plan Properties dialog. (page 116)
New Actual Design Create a new actual design for the selected wellbore (page 116).
New Survey Access the Survey Properties dialog to define the survey name,
contractor, survey tool and tie-on information for this directional
survey. (page 117)
New Attachment Displays the Attachment Properties dialog. Refer to “New
Attachment (Company Level)” on page 69 for more information.
Copy Copy the selected wellbore data to the Clipboard (page 117).
Paste Paste copied wellbore information (page 117).
Rename Use this command to change the name of the well. (page 117)
Delete Delete the selected wellbore and all associated child information
(page 117).
Export Export the selected wellbore’s hierarchical information to an
XML file (page 117).
Import DIMS Surveys Displays the DIMS Survey Import dialog. (page 118)
Targets Access the Target Editor. (page 118)
Properties View or edit the wellbore properties (page 118).
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New Survey (New Wellbore)
Use this command to access the Survey Properties dialog to define the
survey name, contractor, survey tool and tie-on information for this
directional survey. Refer to “Defining New Survey Properties” on
page 264 for more information.
New Attachment (Wellbore Level)
Use this dialog to associate a document or picture (Word, Excel, text
file, JPG, etc.). The document can be of any type with a recognized
extension. Refer to “New Attachment (Company Level)” on page 69
for more information.
Copy (Wellbore Level)
Use this command to copy the selected wellbore from the Well
Explorer and save it to the Clipboard.
Paste (Wellbore Level)
Use this command to paste (insert) the contents of the Clipboard at the
location currently selected in the Well Explorer.
In order for this function to be effective you must have Copied (saved)
wellbore data to the Clipboard.
Rename (Wellbore Level)
Use this command to rename the item. You can also rename the data
hierarchy item by highlighting it and the clicking once on it. Type the
new name in the box that appears around the current name.
Delete (Wellbore Level)
Use this command to remove the selected wellbore from the database.
A confirmation box will open, asking if you are sure you want to delete
the wellbore and all its associated data. Click Yes or No, as appropriate.
Export (Wellbore Level)
Use this command to export the selected Wellbore’s data in XML
format. Includes the hierarchical information above and any child
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information associated with the Wellbore. A dialog will open, allowing
you to supply a directory and filename for the XML file.
Import DIMS Surveys (Wellbore Level)
To access the DIMS Survey Import dialog, a Wellbore must be open.
COMPASS will connect to the DIMS ODBC data sources listed in
DIMS32.INI. If DIMS32.INI is not available, COMPASS will use the
data sources listed in DFW.INI.
Consult your DIMS administrator for details on these INI files and
ODBC connections.
Targets (Wellbore Level)
Use this command to access the Target Editor. A target is a point in a
geological space that is used as an aiming point or volume for directing
Wellbores. Use the Target Editor to define target location and shape.
The form is also used for managing several targets on a Wellbore or a
site.
Refer to “Defining Targets” on page 150 for more information.
Properties (Wellbore Level)
Selecting this command allows you to view or edit Wellbore properties.
The Wellbore Properties dialog opens. The Wellbore Properties dialog
is used to create a new wellbore and to provide information regarding
creation and modification of the wellbore.
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Using the Wellbore Properties > General Tab
Using the Wellbore Properties > Magnetics Tab
Enter the magnetic referencing data for this Wellbore’s operations.
Sample Date
Since the earth's magnetic field changes with time, a date is
required to project the magnetic field. This date may be planned
(extrapolated) or historical (interpolated).Model Name
Select a magnetic model. If 'User Defined' is chosen, you will need
to manually enter declination, dip angle & field strength.
Select a Wellbore type to classify the
Wellbore. This is not essential but may be
useful when filtering Wellbores for
anticollision scans. You can associate a
color with a Wellbore type for plots. Specify
Wellbore Types to appear in the list using
the Company Properties > Wellbore
Types tab.
A Wellbore must start from surface or be
sidetracked from another Wellbore. If it is
sidetracked, select the Wellbore that contains its
starting point.
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Otherwise, these values will be computed using the magnetic model
& sample date.Declination
The angle between magnetic and true north at the sample date and
wellhead location.Dip Angle
The angle that the geomagnetic field is tilted with respect to the
surface of the earth.Field Strength
The magnetic field strength at the sample date and wellhead
location.
Using the Wellbore Properties > Anticollision Colour List
In the Travelling Cylinder and Ladder plots, you may color the
proximity results by measured depth on the reference Wellbore. Enter
into the grid the depth on the reference well to start the applying color
and the color to apply.
Working at the Design Level
Design is the data level directly beneath the Wellbore level and each
design within a wellbore must have a unique name.
A design can be thought of as a design phase. Associated with each
design are a pore pressure group, a fracture pressure group, a
temperature gradient, and a wellpath. A design may have several cases
associated with it, but each case will use the same Pore Pressure group,
Fracture Pressure group, Geothermal Gradient, and Wellpath.
Note: If the design is locked, you can open it in read-only mode but
cannot save it back to the database. You can use Save As to save to
Enter the numeric value for the
depth on the reference well that
you want to start applying the color
to and select the color you want to
apply.
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another design for editing, or Export to a .XML file. Pore Pressure,
Fracture Gradient, Geothermal Gradient, and Wellpath data associated
with a locked design is also locked. (To let you know that there are
unsaved changes to the open design, an asterisk is placed after the design
name in the application title bar.)
A design can be categorized as prototype, planned or actual. The design
icon indicates the category:
You may have several different versions of prototype designs. For
example, assume the geologist wants to analyze two different
formation fracture gradients. This could easily be accomplished by
having two prototype designs that are identical except for the fracture
gradient group. Landmark’s StressCheck, CasingSeat, and COMPASS
applications routinely use designs.
The datum in which the data is viewed and calculated is set at the Well
level.
With a Design selected, the following right-click menu items are
available:
In the Well Explorer, when you right click on a design, the right click
menu displays the following choices
Icon Type of Design
Prototype (no line down the middle and blue circle is white
inside)
Planned (has yellow line down middle of casing and blue circle
has red inside)
Actual (has red line down the middle of the casing and there is
no blue outline for the circle)
Command Description
Open Open the selected item.
Edit Edit the planned or prototype design using the Plan Editor.
(page 123)
View View the actual design. To edit the actual design, you must use
Properties > Survey Program. (page 123)
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Open (Design Level)
Use this command to open the selected design.
New Survey (Actual Designs only.) Accesses the Survey Properties editor.
(page 123)
New
Attachment
Displays the Attachment Properties dialog. Refer to “New
Attachment (Company Level)” on page 69 for more information.
Paste Paste copied design information (page 124).
Rename Rename design. (page 124)
Delete Delete the selected design and all associated information
(page 124).
Export Export the selected design’s hierarchical information to an XML
file (page 124), or DEX file.
Import Import DIMS surveys or a DEX file. (page 124)
Casings Access the Design Casings Editor dialog to enter casing sizes
and depths for each Wellbore to be viewed in graphs and reports.
(page 124)
Formation Access the Design Formation Top Editor. Formation top depths
and lithologies may be included on graphs, wall plots and
reports. (page 125)
Reports Access the Reports dialog to generate a report. (page 126)
Properties View or edit the design properties (page 124).
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Edit (Design Level)
Use this command to edit a planned or prototype design using the Plan
Editor dialog.
View (Design Level)
View the actual wellpath for an Actual Design. You will not be able to
edit the data using this dialog. To edit the Actual Design, use Properties
> Survey Program.
New Survey (Design Level)
Use this command to create a new survey. Refer to “Defining New
Survey Properties” on page 264 for more information.
New Attachment (Design Level)
Use this dialog to associate a document or picture (Word, Excel, text
file, JPG, etc.). The document can be of any type with a recognized
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extension. Refer to “New Attachment (Company Level)” on page 69
for more information.
Paste (Design Level)
Use this command to paste (insert) the contents of the Clipboard at the
location currently selected in the Well Explorer.
In order for this function to be effective you must have Copied (saved)
design data to the Clipboard.
Rename (Design Level)
Use this command to rename the item. You can also rename the data
hierarchy item by highlighting it and the clicking once on it. Type the
new name in the box that appears around the current name.
Delete (Design Level)
Use this command to remove the selected design from the database. A
confirmation box will open, asking if you are sure you want to delete
the design and all its associated data. Click Yes or No, as appropriate.
Export (Design Level)
Use this command to export the selected Design’s data in XML format.
Includes the hierarchical information above and any child information
associated with the Design. A dialog will open, allowing you to supply
a directory and filename for the XML file. Also allows for export in
DEX format.
Import (Design Level)
Use this command to import DIMS surveys or DEX data into the
selected Design.
Casings (Design Level)
Enter casing sizes and depths for each Wellbore to be viewed in graphs
and reports. Casing shoes may be added to the definitive survey or
surveys and plans. In the browser you may copy the casing scheme from
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another Wellbore. You may configure a standard set of casing sizes for
the pick list in the Tools > Casing List Editor.
Casing dimensions (Casing Size and Hole Size) will be added to error
dimensions for anticollision scans, when configured in the Company
Properties dialog. Hole Size is the hole diameter that the casing was run
into. It is used only as the diameter of the reference well in anticollision.
Casing sizes are used for all offset wells.
Formations (Design Level)
Formation top depths and lithologies may be included on graphs, wall
plots and reports. Formations may be added to the definitive survey.
Select Name, Case Size, and Hole
Size from the drop-down lists.
Configure the lists using Tools >
Casing List Editor.
Target can be created
from Formation Top
information.
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Note: Some definitions are required to understand the dipping formation
model.
MD
Is the measured depth of the formation on the Wellbore. This is
normally entered while or after the well has been drilled. The MD
pick comes from cuttings, and logs run while or after drilling.TVD Wh
Is the TVD of the formation directly below the wellhead or vertical
section origin. This is the depth entered during planning. If TVD is
entered then MD will change on the Wellbore.TVD Sys
Is the vertical depth that the formation intercepts the Wellbore. This
field is output only, it will be the same as TVD Wh if the formation
is horizontal (no dip).Lithology
This name is picked from the list of lithologies and is used to build
the texture of the formation column.Dip Angle
This is the maximum angle from horizontal of the formation. (down
dip). The dip angle may change if MD is entered, and is computed
based on the Wellbore interpolation and the TVD below wellhead.Dip Direction
This is the azimuth of the down dip angle.Intercept
This will create a point target where the wellpath penetrates the
formation plane. To enable this button, select a row in the grid by
clicking on the row header with the mouse. The row must contain a
formation that is penetrated by the wellpath.Plane
This will create a rectangular target that mimics the formation
plane. The target will be centered on the vertical section origin. To
enable this button, select a row in the grid by clicking on the row
header with the mouse.
Reports (Design Level)
Use the Reports option to generate many types of reports, including
survey, planning, anticollision, and summary reports. Refer to
“Planning Reports” on page 213 for more information.
Properties (Design Level)
Selecting this command allows you to view or edit Design properties.
The Actual Design Properties tabs are used to create and maintain
properties related to Actual Designs. The Plan Design Properties tabs
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are used to create and maintain properties of planned or prototype
designs.
Using the Design Properties > General Tab
The General Tab is used for Actual, Planned, and Prototype Designs.
Do not check the Planned
(Principal) box if the design is a
prototype. The General tab for an
Actual Design will not display this box
at all.
Notice the title bar indicates that this is a Planned
design rather than an Actual design. The General
tab for an Actual design is very similar to this tab
except the title bar would say Actual Design
Properties and the Planned (Principal) box
would not appear.
Refer to “Using Datums in
EDM” on page 50 for
more information about
datums.
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Using the Design Properties > Tie-on Tab
The Tie-on tab is not used for Actual Designs.
Using the Design Properties > Survey Tool Program Tab
This tab is not used for actual designs. The Survey Tool Program for a
plan is the sequence of survey tools that will be run as the plan is drilled.
It is used to generate survey errors for the planned wellpath. The planned
wellpath represents the entire wellbore from surface to plan TD and is
used when plotting the plan and running anti-collision scans against it.
User Defined: Enter the MD,
INC, AZI, TVD, N/S, and E/W
of the tie point.
From Wellhead: Enter the initial
Inc and AZI at the wellhead.
These fields are disabled if using
the Well Reference Point system.
From Survey/Plan: Choose the
parent survey or plan and enter
the MD at which to tie onto it.
Compass will give error
messages if you enter a depth
outside the depth range of the
parent survey/plan.
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If the plan is tied onto another plan or survey, the tool program from
surface to the tie depth is automatically filled in by Compass. This
portion of the program cannot be edited.
From the tie depth to TD, you may only edit depth ranges and survey
tools. You cannot edit the first Depth From - this is always the plan tie
depth. You cannot edit the last Depth To - this is always the plan TD.
Compass will warn you if you enter depths that are outside the plan
depth range. Compass will also adjust depths so that there are no gaps
between depth ranges.
To add new rows to the program, simply enter a value in the Depth From
cell in the last row of the grid. Compass will automatically update the
To depth in the previous row to match & enter the plan TD in the Depth
To cell.
Depth From
Enter the depth of the first measured station of the survey. It should
not include the tie-in depth if it is measured by another survey
instrument.Depth To
Enter the depth of the last measured depth in this survey section.
When the survey is actually run the actual survey depths will be
used to build the definitive path.Survey/Plan (Wellbore)
Read only. Shows the survey or plan used over the given depth
range. Stations from this survey or plan are used to build the
planned wellpath.Survey Tool
This is the survey instrument used to measure this survey section
from the list of survey tool error models. This defines the error
ellipse over the given depth range.Do Not Use
Indicate that this survey has been planned or run but will not form
any part of a definitive path.Use in Pref.
Use this survey in preference to later surveys. Normally later
survey depths in the program would supersede previous survey
depths, but should a high accuracy survey be planned with
subsequent overlapping lower accuracy surveys, part of the lower
accuracy survey will be overwritten.Program Parts
Examine the state of the program when each of the chosen surveys
is run. This will show both the tie-on sequence for the surveys, but
also the survey instrument sequence when new sections of hole are
drilled.
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Edit Tools
Choose this button to display the Survey Tool dialog, which you
can use to add or edit tools.
Using the Design Properties > Vert Section Tab
This tab is used for actual, planned, and prototype designs. Vertical
section defines the vertical plane or planes to measure the well
displacement. The plane requires an origin and a direction. A number of
vertical sections may be defined and each one will start at a specified
vertical depth. Normally with single target Wellbores you need to define
only one. However, with multiple targets and major changes in
direction, multiple vertical sections will better represent the Wellbore
distances on a section plot.
Angle Type
Select one of several options to automatically determine vertical
section plane from local north:
• Bottom Hole Location (of the definitive survey) - The angle is
calculated from the origin to the last survey point in your
definitive survey.
The vertical section dimension has a zero
point that starts from an origin point. You
may define the vertical section zero point to
start from slot, site center, or user.
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• Target - Select a target from the list of targets and COMPASS
will compute the angle.
• User - Enter the direction of the vertical section plane from local
north.
Azimuth
Enter the azimuth of the vertical section plane.Origin Type
The vertical section dimension has a zero point that starts from an
origin point. You may define the vertical section zero point to start
from one of the following:
• Slot - The vertical section originates at the current slot or well
co-ordinates.
• Site center - The point you defined as the site center location in
Site Properties.
• User - Enter the co-ordinates of the vertical section origin in the
grid as Start N/S and Start E/W. (i.e. sidetrack point). In this case
there may be several origin points to ensure continuity.
Origin N/S and Origin E/W
The origin point for vertical section zero if user defined.From TVD
The vertical depth from Wellbore datum that this section plane
operates from.
Using the Design Properties > Survey Program Tab
This tab is only used for actual designs. The Survey Program for a
Wellbore is the sequence of surveys used to generate the Definitive
survey. At any stage in drilling a well it can be used to compose the
stations for the actual wellpath based on the depths and order in the
program. This dialog is used to configure the survey sequence. Wellbore
position is determined by processing the results of one or more borehole
surveys. As drilling proceeds, surveys are taken of the new hole section
and sections of Wellbore may be re-surveyed using more accurate
survey tools.
This dialog enables you to select which surveys are used to compute the
definitive survey. Whenever the survey program is updated, COMPASS
records the date and the names of the surveys that were used to compile
the definitive survey.
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Chapter
Concepts
Overview
In this chapter, you will be introduced to basic COMPASS features,
including:
� Accessing online documentation and tools
� Using the Status Window and Data Viewer
� Recognizing locked data items
� Using the Menu Bar
� Using the Tool Bar
� Using the Status Bar
� Accessing online help
� Configuring units
4
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Accessing Online Documentation
COMPASS is installed with online documentation to assist you with
using the product. This documentation can be found by using the Start
Menu. The default installation will create a program group titled
Landmark EDM. From here, you can select the software you want to
use, the Documentation sub-group, or the Tools sub-group.
Using the Documentation sub-group, you may select:
� Help - This selection provides access to the online help for all the
EDM software applications. The online help is also accessible from
all windows, and dialogs in the software.
� Release Notes - This selection provides access to the release notes
for all the EDM software applications. Release notes provide useful
information about the current release, including: new features, bug
fixes, known problems, and how to get support when you need it.
� User Guides - This selection provides access to the EDM Common
Installation Guide and the Data Migration Tool Kit user guides.
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Chapter 4: Concepts
Using the Main Window
COMPASS is a Microsoft Windows MDI (Multiple Document
Interface) application. Data entry and analysis are performed in separate
windows that you view simultaneously within a central application area.
COMPASS itself is composed of the distinct tool areas shown below.
Using the Well Explorer
The Well Explorer is a combined browser and status window for
navigating, managing and launching COMPASS data.
The Status View Browser is divided into three sections, and a drop down
Recent Selections List. The section located on the left of the window is
the Status Window. The top right section of the window is the Browser
Window, and the bottom right section of the window is the Data Viewer.
The Status View Browser is always available. You can minimize it, but
you cannot close it.
These are the essential components of Well Explorer. Note that the Well
Explorer display will vary slightly from one application to another. For
Menu Bar
Tool Bar
Datums
Reference
MDI Document Area. Will
display any number of
Status Bar
Depth, Angle & Map Units
Unit Set
Recent Bar
Well Explorer
Viewing Preferences
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136 COMPASS Training Manual Landmark
example, applications that do not use Cases (such as StressCheck,
CasingSeat, and COMPASS) will not display Cases in their Well
Explorer.
Status Window
The Status Window displays the following information. To change
some of these items, use the Viewing Preferences discussed on
page 137.
� The currently open data set including the Company, Project, Site,
Well, Wellbore, and Design.
� Status box stating which Company, Project, Site, Well, Wellbore, or
Design is open.
� Drawing of vertical datum reference with elevation information for
the open Wellbore.
� Drawing of the slot position with north arrow for co-ordinate
information for the open well.
� Vertical section origin and angle.
Status Window
Recent Bar
Browser
Window
Data
Viewer
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Chapter 4: Concepts
� Browser Window (Data Tree)
Viewing Preferences
Use the Viewing Preferences to configure many of the items illustrated
on the Status Window.
Browser Window
The Browser Window is located in the upper right section of the Well
Explorer:
You can use the browser to search for the main Compass data items, like
Companies, Projects, Sites, Wells, Wellbores, Surveys and Plans. The
currently open context is shown in bold typeface.
The browser operates like the Windows 9x/NT Explorer and operates
over the COMPASS data hierarchy in a similar fashion to a directory
tree. For information on the Well Explorer, refer to “Introducing the
Well Explorer” on page 58.
Operations are:
� Left mouse button is used to expand or contract branches of the
data tree and to select.
� Right mouse button has a context sensitive menu. Depending on the
hierarchical level you have highlighted (Company, Project, Site,
Well, or Wellbore) the menu will populate with all of the relevant
Select the unit system you
want to use from the drop-
down list. COMPASS has
two default unit systems,
API and SI, but you can
make your own system.
Refer to “Configuring
Units” on page 146 for
more information.
Select the Datum you want to use
from the drop-down list. Specify
datums using File > Properties >
Well > Properties.
Check the TVDSS box if you want true
vertical depths (TVD) referenced to
the system datum. If the box is not
checked, then TVD is displayed
relative to the datum selected in the
Datum drop-down list. Measured
depths are always relative to the drop-
down list.
Select the coordinate system
you want to use.
Select Grid or True
to specify what you
want to use for the
North reference.
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138 COMPASS Training Manual Landmark
options from the main menu. (New, Open, Edit, Delete, Export,
Import, Report etc.).
� You may use the Browser Window to select additional plans and
surveys for graphs by clicking the left mouse button to check the
boxes associated with the item you want to include on the graph.
� You can use the Browser to "drag and drop" data between
hierarchical levels. For example, you can select a Project associated
with one Company, and copy it to another Company.
Locked Data Items
Both the Status and Browser areas in the Status Window indicate
whether data at a particular level has been locked. This is achieved by
displaying ‘padlock’or ‘key’ icons adjacent to the data. Companies,
Projects, Sites, Wells, Wellbores, and Designs can be locked, as well as
individual Plans and Surveys. This prevents locked data being
mistakenly modified or deleted.
The following graphic depicts Status Window locked data icons or
padlocks:
Concurrency Control
In a multi-user database different users use COMPASS at the same time
to access the same data source. In this environment, it is useful to know
if another user is currently using a data set. The Browser window
indicates when someone is using a design by placing a next to the
A padlock indicates a
locked item.
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Chapter 4: Concepts
design name in the list so users know that someone else is accessing it.
This icon is know as SAM.
Interpreting the SAM color:
� If SAM is red, then one or more users have the design open and you
are restricted to accessing the design in read-only mode.
� If SAM is blue, then one or more users have the design open, but
you still have full read/write access to the design.
Data Viewer
The Data Viewer is located in the bottom portion of the right side of the
Status View Browser. It displays information about data belonging to
the current open item (in the Browser Window), like Templates,
Targets, Tool Codes, Casings, Formations Datum and Annotations.
Recent Bar or Recent Selections List
Recent Selections lists recently opened items. Compass will always
open the last selection but you may use this list to open Companies,
Projects, Sites, Wells, Wellbores, and Designs edited previously.
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Using the Menu Bar
The menu bar provides access to all tools available within the software.
It is organized as follows:
You can select any item within the menus using the mouse or the
indicated keyboard quick keys.
To use the quick keys to select an item, press ALT and the underlined character. For example, to import a transfer file from another Compass
site, one would use the File Import Transfer File menu item, press ALT F M T.
The Survey, Planning and Anti-collision menus are license-driven
through either a dongle, network licensing, or FlexLm file-based
licensing. If COMPASS is unable to locate a license for these products,
the menus are still active, but a message box appears informing you of
the license restriction. This event may also occur for network-licensed
sites when all available licenses are checked out by other users. You also
find that menus are inactive (grayed out) if a wellpath is not currently
open.
Select... To...
File Open data, Create New Items, Import/Export functions,
Data Exchange between different Landmark
applications
Composer When the Wall Plot Composer is active, use this menu
to access many Wall Plot Composer options.
View Launch certain graphs and Legend, Launch Wallplot
Composer.
Planning Access the Directional Well Planning module.
Survey Access the Survey module.
Anti-collision Access the Anti-collision module.
Tools Launch utility functions, configure default graph and
report settings.
Windows Change full size windows, Standard Windows menu
item.
Help Access the online Help, current version info.
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Chapter 4: Concepts
The Survey and Planning modules are mutually exclusive. So, if a
Survey is open, you can’t access the Planning menu and vice-versa.
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Using Toolbars
The toolbar is located below the menu bar and enables quick access to
commonly used functions within COMPASS. Intuitive icons indicate
which functionality is accessed by each icon. Descriptive Tool Tips
appear if you pause your mouse cursor over any icon.
Company
Properties
Survey
Tools
Project
Properties
Targets
Site
Properties
Link to
OpenWorks
Magnetic
Calculator
Geodetic
Calculator
Reports
Wallplot
Composer
3D View
Plan
View
Section
View
Select
Offset Wells
Graph Setup
Casing Editor
Formation
Editor
Design
Properties
Wellbore
Properties
Well
Properties
Templates
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Chapter 4: Concepts
Using Status Bar
The status bar is the information area at the bottom of the COMPASS
window that displays SAM rights, Help, and Units information.
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Accessing the Online Help
The online Help System is remarkably comprehensive and is geared
towards engineering descriptions and solutions instead of the simple
‘What does this button do?’ type Help usually available in other
Windows applications. Much of the Help has been written after
reviewing frequently asked questions from our clients stored in
Landmark’s Call Tracking System. See the Frequently Asked Questions
section in the Help for details.
You access context-sensitive online Help as follows:
• From the COMPASS main menu select Help then Contents.
• Click the Help button located on most dialogs or editors
� Press F1 on your keyboard
The Help functions the same way it does in other Microsoft Windows
applications.
The following graphic depicts the COMPASS Help Contents:
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Chapter 4: Concepts
Finding Information in Help
Once in help, you use the Help Toolbar to find desired information as
follows:
In addition, there are hotspots embedded in the text that provide more
information.
Frequently Asked Questions
The Help file contains a FAQ topic area that can be found in the
Frequent Questions section of the Help file. If you have an urgent
question, it could well be that a number of engineers have already asked
the same question and it is included in the FAQ.
Click... To...
Help Topics Go to the main Help Contents (shown above).
Search by subject areas, search by indexed
keywords, or search through Help database
Back Go to the previous Help topic.
Print Print the current help page.
Browse Keys (<< and >>) Browse through related topics.
Glossary Access a glossary of terms commonly used in
COMPASS.
Click here... To...
Jump Hotspot – (solid
underlined green text)
Jump to another related topic.
Popup Hotspot – (dotted
underlined green text)
View descriptive information in a popup
window.
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146 COMPASS Training Manual Landmark
Configuring Units
The COMPASS Units Management System (UMS) is accessible from
the Tools menu. The essential function of the units editor is to configure
display units for each unit class and organize them into unit sets. Display
units are distinct from storage units. At any time, you may change the
display units used by COMPASS and automatically convert any values
with no adverse affects to the data or results. This also means that you
can share data with other users or clients who use a different unit set;
they automatically see your data in their units.
For applications in WELLPLAN and COMPASS, only some units are
meaningful for expressing unit types. For this reason, Unit Classes (sets
of units for a particular unit type) are defined.
Examples of Unit Classes are:
• Diameters:[mm], [inch], [cm]
• Depth: [m], [ft]
• Dogleg Severity:[deg/100ft], [deg/30m], [deg/100m], [deg/10m],
[rad/30m], [rad/10m]
The following graphic depicts the COMPASS Units Editor.
Each tab indicates a
separate unit system.
Two unit systems, API
and SI, are default unit
systems distributed with
COMPASS.
Select the unit system you want to use
from the drop-down list.
Click the New
button to create
a new unit
system. You
can base the
system on an
existing
system.
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Chapter 4: Concepts
Each data entry field in COMPASS belongs to a Unit Class, and its
value is displayed in the unit defined for that class. Variables that belong
to different classes do not need to be represented in the same type of
units. For example, while Hole Diameter might be represented in inches
(API), Hole Depth might be represented in meters (SI).
You use the Unit Systems Editor to configure a Display unit for each
Unit Class. These unit specifications can be saved so that each time you
use COMPASS, displayed data appears in the desired units.
COMPASS is shipped with two default unit sets, API & SI, that cannot
be edited. They are provided as a starting point for any customized unit
set that could consist of a combination of API and SI units. Additionally,
there are a default set of units within a given class. You cannot add units
to a particular class.
Oil Companies typically create a unit set for their own employees.
Contractors may create unit sets for each of their clients who receive
WELLPLAN or COMPASS reports or graphs.
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Chapter
Planning Module
Overview
The Plan Editor is a mathematical toolbox consisting of a large number
of directional well planning solutions. Solutions are available for a wide
range of planning problems from simple 2-dimensional slant and
S-shaped wells to complex 3-dimensional wells up to and beyond the
horizontal, threaded through any number of targets. Integration with
other Landmark software enables directional well plans to be quickly
evaluated for engineering constraints.
Active plans can be combined with the Anti-collision module and the
Target Editor to provide a powerful decision-making aid. The basic
components of the Plan Editor are:
� Plan Setup
� Planned Survey Tool Program
� Plan Editor Grid
� 2D and 3D Planning Methods
� Project Ahead
� Planned Walk Rates
� Wellpath Optimiser
� Planning Reports
� Plan Export
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Defining Targets
Using Targets
To use targets in well planning, the planner must have the location and
geometry of any drilling and geological targets defined within the
Target Editor. These targets must be assigned to the current Wellpath
before they can be used. Most of the planning methods enable you to
select a target to plan to. By default, the planning methods designs to the
aiming point of the target, though there is usually an Adjust button
available that allows you to manually move the aiming point. If a target
is not defined, the well planner can usually enter the location as a point
in space: TVD, Northing and Easting from the local coordinate origin.
Plans that are designed to target locations remain linked to those targets.
If a target location is changed, all linked plans are updated
automatically. Therefore, the plan and target editors can be used
concurrently while directional well planning.
In COMPASS, a target is a subsurface location (TVD, N, E) with an
assigned geometry and orientation which may be used for planning or
wellpath monitoring. COMPASS enables you to define and assign
geologic and/or drilling targets at the Project level, which may then be
selected by any number of Wellpaths within the Project.
Once created, Targets can be used by the Survey and Planning modules,
and can appear on most of the available graphics and be referenced in
planning and survey reports.
Target Geometry
Each target can have a shape defined about its location. A target can be
geometric (either a Point, Rectangle, Circle, or Ellipse) or non-
geometric (defined as a Polygon with any number of points).
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The following graphic depicts geometric and polygonal targets:
Each target has an aiming point, the location that the Plan Editor
methods aim toward. For geometric targets the aiming point defaults to
the geometric center. However, this aiming point can be offset laterally
and vertically from the geometric center using X & Y offsets and
thickness up and down. Thickness enables a planar depth to be assigned
to the geometrical target. Polygonal targets can have variable
thicknesses defined, which enables wedge or drillers cones to be
modeled. All targets can be rotated about the aiming point and inclined
from the horizontal along any azimuth; this enables a target to model
geologic dip and strike.
Target geometry is discussed in more detail later in this chapter.
Accessing the Target Editor
There are several ways to access the Target Editor, including:
� File > Properties > Project > Targets
� Select a Project or Wellbore in the Well Explorer and then double-
clicking on the target entry in the Data Viewer.
� Click the button on the Tool Bar.
Point RectangleEllipseCircle
Polygonal Targets
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Using the Target Editor
Using the Target List
The Target Editor contains two lists:
Click the Project button to
view all targets for the
project.
Click the Wellbore
button to view only the
wellbore targets.
Check the box associated with
a target to indicate the target is
a Wellbore target.
In the Target Properties section you
can specify the location, shape,
size, and orientation of the target.
Local coordinates are from the local coordinate origin.
Map coordinates are based on the grid system specified using
File > Properties > Project > Properties > Map Info.
Polar coordinates are a distance and azimuth from the local
center.
Lease Line coordinates are specified as distances from the
lease lines. The direction is specified in File > Properties > Site
> Properties > Location.
This is the Target Viewer.
Refer to “Using the Target
Viewer” on page 159 for
more information.
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Chapter 5: Planning Module
� Project targets list: The project list contains all targets in the current
project. To see all the project targets in the site, click the
button.
� Wellbore targets list: The wellbore list is a subset of the project list
and contains targets associated with the current Wellbore. To see all
the targets associated with a particular path click the button.
To allocate a target to a Wellbore, refer to “Allocating Targets to
Wellbores” on page 153.
The buttons are not available if a Wellbore is not open.
Allocating Targets to Wellbores
A target has been allocated to the current Wellbore when the box
associated with the target in the Target List is checked. You may
allocate or de-allocate targets to Wellbores by clicking the box in the site
list. You may also allocate a target to multiple Wellbores using this
mechanism.
Defining the Target Geometry
Use the Geometry tab to enter information on the target’s shape. A target
can be a simple point location, a radius about an aiming point, a box or
rectangular shape to define lateral tolerance, an ellipse, or a complicated
polygonal target with any kind of irregular geometry.
The Geometry tab in the Target Editor is used to define the shape for the
selected target or for a new target. When you select a shape on this tab,
Note: Adding targets to Projects and Wellbores...
When you add targets with the Project toolbar icon depressed, you must
specifically allocate the target to a wellbore in order for it to be used. When you
add targets with the Wellbore toolbar icon set, targets are automatically allocated
to the current wellbore.
Note: If a Site is Not Open...
If no site is open or if the open site has no center location, you can only locate
targets using map or geographic co-ordinates.
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154 COMPASS Training Manual Landmark
appropriate entry fields will be enabled so that you can define the shape
in detail.
Target shapes can be one of a number of pre-defined shapes, including:
� Circle - A circle or a semicircle or a pie slice. Refer to “Circular
Targets” on page 154 for more information.
� Ellipse - An ellipse or a semi-ellipse. Refer to “Elliptical Targets”
on page 155 for more information.
� Rectangle - Square or rectangle. Refer to “Rectangular Target” on
page 156 for more information.
� Polygon - User defined shape, you can edit the points individually.
Refer to Target Shape
Circular Targets
The following graphic depicts the Circular Target Editor window:
This window enables you to enter a circular target or, by giving the
circle height and a dip angle, you can define a cylinder.
Select the desired
target shape.
Offset from Target Centre
fields enable 3D target
geometry and orientation to be
defined. You can offset the
geometric center of the target
from the plan-to point by
entering X (local East) and Y
(local North) offset.
Start and End Angles enables
‘pie-shapes’ to be defined for
circular and elliptical targets.
For a full circle shape, use zero
for the start and end angles.
Type a value in
the Up and Down
fields to change a
circular target to
a cylindrical
target. The top of
the target is Up,
the distance
above the plan-to
point. The bottom
of the target is
Down, the
distance below
the plan-to point.
Dip angle is the angle you want to be on at the
target. This is 90° minus the inclination of the
target. This is the direction a ball would roll if
placed in the formation bedding plane.
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Elliptical Targets
The following graphic depicts the Elliptical Target Editor window.
Rotation angle enables target
to be turned relative to Site
North. Target rotation is about
the aiming point.
Thickness Up and Down
enables the aiming point to be
offset vertically within the
target.
Formation Plane parameters
enables geologic dip and
down dip direction to be
specified, for example, to
model a bedding plane. This
may be different from target
rotation.
For Semi-Minor,
enter the
dimension of the
ellipse along the
local North/South
axis. For Semi-
Major, enter the
dimension of the
ellipse along the
local East/West
axis.
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Rectangular Target
The following graphic depicts the Rectangular Target Editor window.
Note: Defining equivalent formation thickness.
Target up and down thicknesses are used to define equivalent formation thickness.
This method is useful because you can define the aiming point at a given depth
below the formation top. For example, if you have a dipping formation that is 30m
thick but want to drill down dip 5m below the formation top, you define the aiming
point as 5m up, 25m down. This method is applicable to all target geometries.
These parameters
define the size of the
target. Length is
parallel to the local
N/S, providing no
orientation is
applied.
Enter the orientation of the
target from local north. The
orientation is zero when
aligned to local north and
increases clockwise.
You can offset the
geometric center of
the target from the
plan-to point by
entering X (local
East) and Y (local
North) offset.
Type a value in the Up and
Down fields to change a
rectangular target to a
cuboid target. The top of
the target is Up, the
distance above the plan-to
point. The bottom of the
target is Down, the
distance below the plan-to
point.
Type the dip angle you want to be on at the target. This is 90° minus the inclination of
the target. Type the azimuth (direction from local north) of the down dip direction. This
is the direction a ball would roll if placed in the formation bedding plane. This is not the
orientation of the target shape.
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Chapter 5: Planning Module
Polygonal Targets
The following graphic depicts the Polygonal Target Editor:
A polygon can have any number of points defined on it using the points
defined using the grid (above).
There are three methods available to define points on a polygon:
� X and Y: Enter local X and Y coordinates from the target aiming
point to define a polygon shape. By default, the last point is joined
to the first to close the polygon. The Y dimension is parallel to the
local N/S, providing no orientation is applied.
� Map E and Map N: Alternatively enter the map coordinates of the
target as given by the geologists. The Local X and Y are computed
based on the target center. Note that if the target center is moved,
these periphery points move as well.
� Well Viewer – Define Polygonal Targets: With the target created,
press the Define Polygonal Targets icon . The viewer displays
a plan view of the target, on which you can use the mouse to click
each point on the polygon. Depress the icon after all points are
clicked, and the target editor will join up the first and last points.
Each point on a polygon
may be given its own
name or label.
Wedge targets may be
defined by changing
thickness Up and Down
for each polygon point.
Enter the orientation of the
target from local north. The
orientation is zero when
aligned to local north and
increases clockwise. If you
define a dip angle, this is
the down dip direction of
the equivalent formation.
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Defining Drilling Targets
If the geologist gives you a target with X dimensions and you drill to it
using MWD, you may hit it near the edge. When the path is later
surveyed using a gyro, quite often the wellbore ends up outside the
target.
To prevent this, the planners should reduce the geologists target by the
expected survey error radius to be found by drilling with MWD (maybe
tied to a gyro at the previous casing). The reduced target is known as a
drilling target. It is a zone within the geological targets that, when drilled
within and monitored using survey instruments with inaccuracies, will
stand a good chance of hitting the geological target boundary.
The drilling target tool creates a new target that has been reduced in size
from the original by the survey errors at the target depth. It requires a
target that is big enough to fit the survey errors and a survey program
that penetrates the target
It is recommended that you create a survey program from a plan with the
survey tools for the situation when drilling the final section of the hole
to the target (i.e. gyro in intermediate casing and MWD in open hole).
The drilling target tool may be used to design a cost effective survey
program applied to the given geological target sizes.
Select Design
Use this tree control to select the wellbore design containing the
survey program, and hence the survey errors, you want to use to
compute the drilling target.Confidence Level
Enter the confidence level (1% - 99%) required to hit the target
using the survey errors from the selected design.Create Drilling Target
Once a design has been selected and a confidence level entered,
press this button to create the drilling target.Delete Drilling Target
If a drilling target exists, press this button to delete it.View Points in NotePad
Press this button to display the computed target points in text
format.
See “Drillers Target Algorithm” on page 380 for an explanation of the
difference between Geologist’s and Driller’s targets.
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Chapter 5: Planning Module
Using the Target Viewer
The target view displays the currently selected target, which you can
toggle as a Section, Plan, or 3D view with the usual 3D tools available.
You can use the Target viewer to define polygonal targets and to change
the landing point for directional well planning calculations. Refer to
“Polygonal Targets” on page 157 for more information on using the
Target Viewer for designing polygonal targets.
Target Landing Point Adjust
When planning or doing project ahead, the target viewer has another
use. If a target is selected from a drop-down list, click to
adjust the landing point. This invokes the target view in adjust mode.
Click anywhere on the section or plan view to adjust the landing point.
The plan or projection immediately updates the calculations using this
new point. This does not change the target location.
To change the landing point for planning calculations:
The landing point or aiming point is defined in the Target Editor.
1. Create a new plan or open an existing plan.
2. Select a planning method that lets you select a target. For example,
a 2D slant well.
3. In the Plan Editor, select a target.
4. Click Adjust.
5. In the Target View window, move the cursor to the coordinates you
wish to aim for, and click the left mouse button.
6. The plan is automatically re-calculated to hit that point.
• To change the horizontal location click the plan view icon .
• To change the vertical location click the section view icon .
• You can also type in the landing point coordinates and click Set.
• To revert to the original coordinates click Reset.
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Creating a Plan
When a New Plan is created, the Plan Properties dialog automatically
appears to allow you to identify the plan. Plan Properties is similar to
Survey Properties. There are several tabs on the dialog to facilitate
creating the plan.
Naming the Plan and Defining the Depth Reference Point
The following graphic depicts the Plan Setup Window.
Specifying the Tie-On Point
Similar to a survey, a Plan must have a defined tie-on point to act as the
starting point of the plan. There are three choices of tie-on point
Lock the plan to
prevent other users
from changing it.
Check the
Planned
(Principal) box to
indicate this is the
final plan, rather
than a prototype
plan. You can only
have one principal
plan for each
Wellbore.
Use the pull-down
menu to select the
depth reference datum.
You define the datums
that appear in this list
using the File >
Properties > Well >
Properties > Depth
Reference tab. Refer to
“Working at the Well
Level” on page 108.
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Chapter 5: Planning Module
methods. The tie-on point can be defined explicitly, tied to the wellhead
location, or calculated based on a specified measured depth.
Plans must be Tied-On to define a
starting point and orientation. Tie-on
methods are:
• User Defined: Use this method to
explicitly define the tie-on point.
• From Wellhead: Specify the
inclination and azimuth at the
wellhead. These fields are disabled
if you are using the Well Reference
Point system.
• From Survey/Plan - Choose the
parent survey or plan and enter the
MD at which to tie onto it.
COMPASS will give an error
messages if you enter a depth
outside the depth range of the
parent survey/plan.
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Defining the Survey Tool Program
Enter the depth of the
first measured station
of the section. It
should not include the
tie-in depth if it is
measured by another
survey instrument.
Survey/Plan (Wellbore) displays the
survey or plan used over the given
depth range. Stations from this survey
are used to build the planned wellpath.
This is the survey instrument used to
measure this survey section from the list of
survey tool error models. This defines the
error ellipse over the given depth range. To
create a new tool, use File > Properties >
Company > Survey Tools.
Check Do Not Use to indicate that this section has
been planned but will not form any part of a
definitive path.
Check the Use in
Pref. box to use this
survey in
preference to later
surveys. Normally
later survey depths
in the program
would supersede
previous survey
depths, but should
a high accuracy
survey be planned
with subsequent
overlapping lower
accuracy surveys,
part of the lower
accuracy survey will
be overwritten.
Program Parts is
only available when
there is more than
one line in the grid.
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Specifying the Vertical Section
Vertical section defines the vertical plane or planes to measure the well
displacement. A number of vertical sections may be defined and each
one will start at a specified vertical depth. Normally with single target
Wellbores you need to define only one. However, with multiple targets
and major changes in direction, multiple vertical sections will better
represent the Wellbore distances on a section plot.
Use Angle Type to select
one of several options to
automatically determine
vertical section plane
from local north.
Select the target type
from the pull-down menu.
From the pull-down list, select the
starting point of the vertical
section.
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Using the Plan Editor
The purpose of the Plan Editor is to generate a series of curve types to
form a planned wellpath trajectory to one or more target locations. The
Plan Editor has three areas: an interactive plan grid, a number of plan
method windows for data entry and calculation, and a toolbar. The plan
grid is always present and displays all plan sections and enables key
parameters of each row to be changed. The plan method windows are
used to define individual curves or profiles. The plan method windows
appear when you activate one of the method toggles.
COMPASS has over 20 planning methods. Some methods are divided
into subgroups, accessed from the planning method icons. The planning
methods can be divided into 2-dimensional tools, 3-dimensional tools
and the Wellpath Optimiser.
Each planning solution consists of rows displayed in the Plan Grid. A
row is a line in space with a constant dogleg, build, or turn rate. Different
planning methods construct a different number of rows. For example:
� Hold adds one row
� Slant Well adds three rows
� Thread Targets adds multiple rows
The Plan Editor is similar to the Survey Editor. Rows are added to the
grid using the different planning methods. Multiple planning methods
can be used when constructing a single plan. Like the Survey Editor, the
keyboard can be used to insert new sections at any point in the plan, or
delete sections no longer required.
Rows in the grid are mathematically linked together by the planning
method that was used to construct them. Therefore, deleting a particular
row in the grid results in all rows linked to that method being deleted as
well. To edit a section in the plan, click on the relevant row in the grid,
and the plan method for that section appears.
Accessing the Plan Editor
You can access the Plan Editor in the following ways:
� The Plan Editor is automatically displayed after you finish creating
a plan using the Plan Design Properties tabs.
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� You can double-click on an existing plan in the Explorer to open an
existing plan.
� Use Planning > Open Plan and select the desired plan from the list
of existing plans.
The following graphic depicts the Plan Editor.
Don’t like what you last
changed, click Undo or Redo.
Plan Design can be quickly accessed from
the tool bar. Refer to “Creating a Plan” on
page 160 for more information on using the
Plan Design dialog.
Plans can be
generated through
more than one target.
The plan grid is interactive; white cells
are editable—change a value and the
plan re-calculates.
Plan method toggles are
used to choose which plan
method is used. Different
methods can be combined to
form a wellpath through
multiple targets.
When a Plan Method toggle is
activated, the plan method
window displays the inputs
required to calculate sections of
that method.
When values have been entered
for the plan method, hit the
Calculate button to generate a
trajectory.
Some plan methods have
sub-method buttons.Use the Planned
Wellpath tab to view
survey data generated
from the plan.
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Plan Grid
The plan grid is always present and displays the geometry data for the
plan trajectory. Each row in the plan grid is equivalent to a survey
station or change point. In the grid, a plan section can contain between
1 and 6 rows, and the full plan trajectory may contain a number of plan
sections joined together. The columns of the grid are as follows.
� MD (Measured depth)
� Inc (Inclination)
� Azi (Azimuth)
� TVD (True Vertical Depth)
� N/S (North/South)
� E/W (East/West)
� Vsec (Vertical Section), Projected vertical section distance along
plotting plane.
� Dogleg (Dogleg Severity), Curve rate from the previous station to
this.
� Tface (Toolface angle), Toolface orientation to get from the
previous station to this.
� Build (Build Rate), Rate of change of inclination with depth. Build
is +ve and Drop is –ve.
� Turn (Turn rate), Rate of change of azimuth with depth. Right is
+ve and Left is –ve.
� CL (Course Length), The measured depth distance from the
previous station to this.
� Type (Plan section), Indicates the plan method associated with the
plan section, marked on the 1st line.
� Target (current target for this row). Name of the target at the end of
this plan section.To Edit directly into the grid
Selecting the Planning Method
In the Planning Methods section of the Plan Editor there are several
methods to select from. Your selection will determine the input data
requirements that will be displayed in the Plan Method Window. See
“Planning Methods” on page 171 for more information on planning
methods.
Using the Plan Method Window
The Plan Method Window portion of the editor displays the input
required depending on the Planning Method selected using the toggles
in the middle of the editor. When the required inputs have been filled,
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click Calculate and the data will be input in the Plan Grid portion of the
dialog. See “Planning Methods” on page 171 for more information on
planning methods.
Using the Plan Editor Toolbar
The planning toolbar is located at the top of the Plan Editor. There are a
number of plan options from the toolbar:
• Save As and Save the plan. Save this plan by another name
• Undo and Redo the plan calculations: Restore the last plan
calculation.
• Plan Set-up: Edit the plan detail and tie-on information.
• Import: Import plan data from the clipboard or a file.
• Thread Targets: Construct a trajectory through several targets.
• Apply Walk: Apply azimuth drift where expected in rotary
drilling.
• Interpolate: Use the Interpolate button to interpolate between
two survey data points.
• Wellpath Optimiser: Optimize a plan for torque/drag, construct
drilling limits plots or evaluate redrill options on idle wells.
• Projection Ahead: Quick calculation of vector to hit a target.
• Plan Comments: Click to access the Annotations dialog.
Annotations are comments on the Survey/Plan that do not fit into
the category of Casings or Formation Tops: Examples of
possible use of annotations include: top of fish, sidetrack point,
MWD Check Shot, and Final Depth (TD). Annotations may be
added to wall plots and reports. Predefined auto-annotations can
be added to the plan as well.
• Create Target: Use Create Target to create a target from a row
of plan data. Highlight the row, click the Create Target toolbar
Save and Save As
Undo or Redo
Plan Design
Properties
Import Plan Data
Thread Targets
Apply Walk
Interpolate
Wellpath Optimizer
Project Ahead
Plan Comments
Create Target
Close
Help
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button, and the target will be created and added to the File >
Properties > Project > Targets list.
Adding a Plan Section
To add a plan section:
1. Select the last line empty line in the grid, then select a Planning
Method using the radio buttons.
2. Fill in the entry fields that are displayed in the Plan Method
Window section of the Plan Editor dialog.
3. Click the Calculate button to compute the results.
4. Click on the next line in the grid to accept the results and start on
the next plan section. Or click the undo button to reject the
calculations and close the curve data entry fields.
Deleting a Plan Section
To delete a plan section:
1. Click on a row within the plan section you want to delete.
2. Press the Delete key on your keyboard.
Editing the Plan Grid
Once plan section data has been calculated, you may edit the input
values directly into the grid. Alternatively, the last line in the grid may
be used to add plan sections directly. When adding lines to the end of the
plan, only certain combinations of parameters will work. At least three
numbers must be entered (or two if DLS=0).
The data combinations are in listed order below:
Note: Deleting a plan section...
You cannot delete individual rows of a plan section. You must delete the entire
plan section.
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1. If Dogleg is defined as zero, then compute a straight line to one of
MD, TVD, or VSec.
2. Inc, Azi and one of MD, TVD or Dogleg. (Inclination, Azimuth
projections)
3. Dogleg, Toolface and one of MD, INC, AZI or TVD.(Dogleg
Toolface projections)
4. N/S, E/W and TVD (constant curve to a point, VSec may be used
instead of N/S and E/W)
5. MD and two of the following Inc, Azi, Dogleg, Toolface.
To Highlight Plan Sections in Views (plots):
Highlight a row in the Plan Grid, and when that plan is displayed in 3D,
section or plan view, the corresponding plan section will be highlighted
in the plot.
Incremental Measured Depths
The planning algorithms remember incremental measured depths, rather
than absolute measured depths. What this means is illustrated in the
following example. A plan to a target has a rathole of 300’; then the
target was moved, and the plan angle changed. The plan would keep the
300’ rathole even though the final TD depth changes.
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Viewing the Planned Surveys
Use the Plan Editor > Planned Wellpath tab to view the planned
trajectory that was generated based on the plan.
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Planning Methods
Plan methods are selected by clicking a radio button on the Plan Editor.
2D planning methods within a vertical section include Slant and S-Well
design; 3D planning methods and tools include Build/Turn curves for
rotary drilled sections, Dogleg/Toolface curves for steerable drilling
design, Optimum Align, Thread Targets, and Nudge. Additional
planning methods are Hold to add a section with no build or turn, Walk
to apply predicted walk tendencies to hold sections in the plan, and the
Wellpath Optimiser, which is used to optimize the wellpath trajectory
for mechanical constraints, lowest directional drilling costs, or least
anti-collision risk. A Project Ahead tool enables the bottom of the plan
to be projected to a target.
COMPASS has a number of planning methods suitable for different
types of directional drilling assemblies. All these tools construct
mathematical curves. When entering parameters for a planning method,
COMPASS always constructs a path if it is mathematically possible.
Sometimes this results in a peculiar wellbore trajectory (see the
following illustration as an example). A drilling engineer should be
capable of detecting these types of plans, and adjusting the plan
parameters as necessary.
If an engineer enters parameters that result in a plan not being
mathematically possible, warning messages appear with a brief
description of the problem and an indication of what parameter requires
changing. For example, a low build-rate parameter can result in the
wellpath not being able to build in the measured depth needed to get to
a target location.
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The following graphic depicts an unexpected Wellpath Trajectory using
Positive Build Rate:
2D Directional Well Planning
The 2-dimensional well planning tools construct wellpath trajectories
that follow the plane of a vertical section. That is, there is no turn from
the slot to the final target. COMPASS provides two methods for
planning 2D wells: Slant well, and S-Well. A slant well is a simple
Hold-Build-Hold profile, whereas an S-Well can be a Build–Hold–
Drop-Hold profile or a Build-Hold-Build-Hold profile.
Slant Well Design
The following graphic depicts 2D Slant Well Design Parameters:
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To design a Slant well:
1. Type in the coordinates of the point to aim for or select a target.
2. Check two of the unknowns from the list of four below. Example
unknowns are 2nd hold length and Maximum Angle.
3. Enter the two known parameters:
• 1st Hold Len - Length of initial hold section before the kick-off
point, or more simply the kick-off depth. Enter zero if you wish
no kick-off length.
• 1st Build - The build-up rate.
• Maximum Angle Held - The tangent angle of the profile.
• 2nd Hold Length - The length of the tangent hold section.
4. When ready to calculate press to compute.
Like all Planning methods, the entry parameter values can be changed,
or the parameters checked can be changed, other parameter types
defined, and the plan re-calculated as many times as necessary without
having to exit from the drop-down window.
S-Well Design
An "S" well has three sections—Build - Hold - Build/Drop, and is
defined by seven parameters. You can also add a hold for the kick-off
Slant is the selected
planning method.
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The following graphic depicts 2D S-Well Design Parameters:
To enter a 2D -’ S’ well profile:
1. Type in the coordinates of the point to aim for, or select a target.
2. Check two of the unknowns from the list of seven below. Example
unknowns are 2nd hold length and Maximum Angle.
3. Enter the five remaining parameters:
• 1st Hold Length - Length of initial hold section before the
kick-off. Enter zero if you wish no length before the kick-off.
• 1st Build Rate - The build-up rate.
• Maximum Angle Held - The intermediate tangent angle of the
profile.
• 2nd Hold Length - The length of the intermediate tangent
section.
• 2nd Build Rate - The second build or drop rate (+’ve or –‘ve).
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• Final Inclination - The inclination you want to achieve at the
target.
• Final hold length - The distance from the end of the last build
to the target. Enter zero if you wish no straight section before
the target.
The following graphic depicts an S-Well Plan Example:
The example above displays a planned S-Well that is planned to target
T9 with the kick-off point at 1500ft, initial build rate of 2º/100ft, second
drop rate of 3 º/100ft, to a final inclination of 10º,with a final hold length
to the target of 1450 ft. With these input parameters, the calculated
inclination of the tangent section is 62.86 º, with an interim hold length
of 3298.7ft. The calculated plan is shown above in 3D (left) and Vertical
Section (right), with each planned section highlighted with boundary
lines.
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3D Well Planning
3D planning methods assume that the well is drilled under some form of
directional control, where the well can be turned to a given azimuth from
a particular measured depth.
Build/Turn Curves
The mathematics of Build and Turn curves assumes that the wellpath is
wrapped around the surface of a cylinder. The shape of the wellpath is
resolved into two planes, vertical (inclination) and horizontal
(direction). The build rate is the rate of change of inclination, and turn
rate is the rate of change of direction or doglegs in the vertical and
horizontal planes respectively.
Build and Turn curves are constructed assuming that the sections are
drilled using a rotary drilling assembly. A number of sub-methods are
available to plan different types of Build-Turn curves, utilizing different
types of available information during the design.
The following graphic depicts the Build / Turn Curves Planning Models:
Build-Turn sub-methods are selected by clicking the appropriate icon at
the bottom of the plan method window. Selecting different icons results
in different parameter fields being active and inactive. Active fields
require a value for the sub-method to work. Inactive fields are calculated
using the entered parameters.
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The following graphic depicts a Build-Turn Drop Down Layout.
Eight different sub-methods are available:
Click...Click To...o...
Build & Turn to Vertical Depth - Apply a build and turn
rate until the specified measured depth or course length.
COMPASS calculates the final TVD, inclination, azimuth,
northing, and easting.
Build & Turn to True Vertical Depth—Apply a build and
turn rate until the specified true vertical depth. You can
specify a TVD or select a target to define the TVD.
COMPASS calculates the final measured depth, northing,
easting, inclination, and azimuth.
Build & Turn to Inclination—Apply a build and turn rate
until the wellpath reaches a certain inclination. COMPASS
calculates the final location, measured depth, and azimuth.
Build & Turn to Azimuth—Apply a build and turn rate
until the wellpath reaches a certain direction. COMPASS
calculates the final location, measured depth, and
inclination.
Tangent to Point—Enter build and turn rates, and
COMPASS adds three sections. It applies the build and turn
rates until pointed to either the correct direction or
inclination, whichever can be achieved first. The second
section is either a build or a turn to complete the projection.
If pointed to the correct inclination, then a turn is applied to
reach the required direction. If pointed in the correct
direction, then a build or drop is applied to reach the
required inclination. The wellpath is now pointing at the
target, so the third section is a hold to target.
Plan to Point—Enter a point or select a target to aim for.
COMPASS computes the build rate and turn rate required to
hit the target in one curve.
Build-Turn sub-method icons. These
activate the required parameter
entry fields when pressed.
Some B/T Methods enable a target
TVD or location to be selected. If a
target is selected, the Target Adjust
feature is also available.
Required fields
are active.
Calculated fields
are greyed out.
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Dogleg/Toolface Curves
The mathematics of Dogleg / Toolface curves assumes that the wellpath
is wrapped around the surface of a sphere - a circular curve with
orientation defined by toolface and radius defined by dogleg. Toolface
is the direction from high-side of the hole. Toolface is 0º at high-side and
180º at low-side. Looking down the wellbore, toolface is positive
clockwise and negative anti-clockwise. If the wellbore has no
inclination, toolface is referenced to local north.
Dogleg-Toolface curves are constructed assuming that the sections are
drilled using a steerable drilling assembly. A number of sub-methods are
available to plan different types of Dogleg-Toolface curves utilizing
different types of available information during the design.
Online by TVD—Enter a point or select a target to aim for.
Specify the depth (True Vertical Depth) by which you want
to be online to hit the target. COMPASS adds two sections, a
build turn section to get the wellpath online by the TVD,
then a hold section to the target.
Align by Inclination—Enter a point or select a target to aim
for. Enter the inclination you require and the build and turn
rates of the curve. At the end of the curve, the wellpath
direction is aligned with the target and at your required
inclination.
Click...Click To...o...
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The following graphic depicts the Dogleg-Toolface Curve Sub-
methods:
The same as Build-Turn curves, Dogleg-Toolface curve sub-methods
are selected by pressing the appropriate icon at the bottom of the drop
down layout.
The following graphic depicts the Dogleg-Toolface Drop Down Layout:
Depending on what sub-
method is selected, the
appropriate parameter
fields are activated.
After Calculating, the greyed out
fields display their calculated values.
Plan to tangent to a point
generates 2 sections: either Hold-
Curve or Curve-Hold.
The Dogleg-Toolface sub-methods
are the same as Build-Turn curves,
except the calculated wellpath shape
is different.
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Eight different sub-methods are available:
Click... To...
Apply Dogleg / Toolface to Measured Depth—Apply a
Dogleg on an initial toolface angle until the specified
measured depth has been reached. COMPASS calculates the
final TVD, inclination, azimuth, northing, and easting.
Apply Dogleg / Toolface to True Vertical Depth—Apply a
Dogleg on an initial toolface until the specified TVD has
been reached. You can specify a TVD or select a target to
define the TVD. COMPASS calculates the final measured
depth, inclination, azimuth, northing, and easting.
Apply Dogleg / Toolface to Inclination—Apply a Dogleg
on an initial toolface until the wellpath achieves a certain
inclination. COMPASS calculates the final measured depth,
TVD, azimuth, northing, and easting.
Apply Dogleg / Toolface to Azimuth—Apply a Dogleg on
an initial toolface until the wellpath reaches a certain
direction from local north. COMPASS calculates the final
measured depth, TVD, inclination, northing, and easting.
Tangent to Point—You enter a Dogleg and COMPASS
adds two sections. It computes the initial toolface of the
dogleg section and the length of hold required to hit a target
or user-defined point. If you want the dogleg section before
the hold, click Curve-Hold or Hold-Curve for the reverse.
The length of the Hold section is dependent on the dogleg
entered.
Plan to Point—Enter a point or select a target to aim for.
COMPASS computes the radius of the dogleg and initial
toolface to hit the target in one curve. This type of plan
could be expensive in directional drilling costs. However,
the method is very useful, as it calculates the minimum
dogleg required to steer between two points. COMPASS
calculates the final MD, TVD, inclination, and azimuth of
the wellpath.
Online by TVD—Enter a point or select a target to aim for.
Specify the depth (True Vertical Depth) by which you want
to be online to hit the target. COMPASS adds two sections: a
curve to get you online by the TVD, then a hold section to
the target.
Align by Inclination—Enter a point or select a target to aim
for. Enter the inclination you require and the dogleg of the
curve. At the end of the curve, the wellpath direction is
aligned with the target and at your required inclination.
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The following graphic depicts a Dogleg-Toolface Plan Example:
The above example displays Dogleg-Toolface planned sections from
target T8 to T9. The entire plan consists of an S-well design to T8
followed by the Dogleg-Toolface curves. Looking at the Dogleg-
Toolface Drop-Down layout, the plan was constructed using the Plan to
Tangent a Point sub-method with a dogleg of 1º/100ft defined to target
T9 selected from the drop-down menu. The two sections are ordered
Curve, then Hold.
Build-Turn vs. Dogleg-Toolface
As discussed in the last two plan method sections, Build-Turn and
Dogleg-Toolface plan profiles have a significantly different geometry.
Build-Turn plans approximate to Radius of Curvature curves that follow
the surface of a cylinder. These curves emulate rotary drilling where
build and walk are predicted. Build-Turn can also design a ‘flat turn’
where the inclination remains constant, for example, when sidetracking
to a different azimuth.
Dogleg-Toolface plans construct a Minimum Curvature geometry that
follows a ‘great circle route’ around the surface of a spheroid. Dogleg-
Toolface curves cannot be used to design a flat turn; the inclination
changes through the turn. For short turns, dogleg and toolface
Slant Well design to target T8
Dogleg-Toolface curve-hold
design from target T8 to T9
Steer from T8 with 1.0° dogleg to
line up on T9
Hold to hit T9
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orientation remain constant. For larger turns, Dogleg-Toolface curves
cannot construct a path with constant dogleg and toolface orientation;
over the turn you’ll find that they change. This effect can be
considerable over a long distance.
Optimum Align
The Optimum Align planning method adds three sections: Curve, Hold,
and Curve (also called Steer – Hold - Steer). You can specify a final
inclination and direction for the end of the final curve, or, if you select
two targets, COMPASS computes the inclination and direction between
them for you. If you select a single target, COMPASS lines up on the
target to plan the well down dip.
The following graphic depicts Optimum Align Planning Methods:
To build an Optimum Align profile:
1. Set restrictions on the curve shape in one of three ways:
• Doglegs—Specify the doglegs of both curves.
• TVDs—Enter the start and end TVD of the intermediate hold
section (or TVD at end of first turn, TVD at start of second turn).
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• Tangent Length—Enter the length of the intermediate hold
section, COMPASS calculates the TVDs and Inc/Azi. If you
enter 0 for the tangent length, compass will compute a “curve-
curve” trajectory which has no tangent length.
2. Select the first target to land the wellpath. You can adjust the
landing point vertically/laterally using the Target Adjust tool. You
can add a short section before the first target by specifying Hold
length with or without a build rate before hitting the first target.
3. Determine the final inclination and azimuth using one of the
following two methods:
• Selecting a second target to follow on to:
• Pick a target. The target you want to hit.
• Line up on target. The target you want the wellpath to line up on
at the end of the second curve. This target is remembered in the
plan, and a hold is computed between the two targets.
• Defining the End Vector at the target:
• Pick No Target (Freehand). If Target 1 has a dip and strike,
COMPASS assumes you want to plan down dip and calculates
Inclination and Azimuth accordingly. These are defaults that can
be changed. If you want to plot sensitivities in the wellpath
optimizer based on N/S & E/W coordinates, you must enter a
freehand target. When doing so, these parameters will appear in
the profile grid for editing.
• Inc - Enter the final inclination required.
• Azi - Enter the final required direction.
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The following graphic depicts an Optimum Align Plan example:
The example above displays an Optimum Align plan to target T8
defined using two doglegs. When the plan hits target T8, the wellpath
trajectory lines up to point directly at T9 so the well can be held to hit
T9. This type of method is very effective to plan a well with the
directional drilling completed top hole to limit costs. Deeper in the well
after hitting T8, the well can be drilled with a stiff assembly and held to
the final TD.
You can enter a short section before the first target by specifying Exit
length and build rate on the tangent length line.
The project back feature can be used to achieve similar results. Project
back is also used to create “soft landings” into a target.
Kick Off Point
T9
First Curve section from Kick Off Point to start
of Tangent section, DLS = 2.5 deg/100ft
Tangent section from end of first turn to start of
second turn
Second Curve section from Tangent section to
target T8, DLS = 3.0deg/100ft
Simple hold section to hit second target T9
Plan to hit target T8 with wellpath orientation
aligned with target T9.
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To create a “locked” up section between two targets:
1) Use optimum align as describe above to design to the 2nd target (i.e.
the final target).
2) Project back and select the first target.
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3) Create a “soft landing” into Target 1 by highlighting the row in the
planning grid containing Target 1 and then project back again. Enter the
Course Length (CL) required and the build rate into the target. Then
calculate.
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Hold Tool
The HOLD tool is a very useful utility for defining planned kick-off
points, or extending the trajectory beyond a target.
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You can add a straight line projection to either a MD, TVD, or VSec:
Thread Targets
Click the Thread Targets button on the Plan Editor to access the
Thread Targets dialog.
Thread targets plans curved profiles through a series of targets, with a
number of plan methods available between each pair of targets. The tool
is very useful for quickly generating rough plans through a number of
targets to see what magnitude of doglegs are required to plan through
them. It is also commonly used to plan wells up-dip, using decreasing
TVD targets.
Select... To...
MD Enter the measured depth to project to. If the MD is
less than current MD of the plan, COMPASS
assumes you wish to apply an additional MD. For
example if your plan is at 5410 ft MD and you say
you want to hold to 90ft, COMPASS adds 90ft to
the plan giving a final MD of 5500 ft. If you typed
in 6000ft, COMPASS adds a hold of 590 ft to the
plan.
TVD You can specify the vertical depth of a target by
picking a target or entering a TVD
VSEC You can specify the vertical section distance by
selecting a target or entering a distance
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The following graphic depicts the Thread Targets Planning Options:
For each one of the Planning methods, the Thread Targets tool also
enables the user to select how the targets are sorted. The options are by
increased displacement from the slot origin, descending TVD ascending
TVD or by Name. The last option enables targets to be sorted in any
order using the order that the targets were placed in the thread list.
The following graphic displays the Target Threading sort methods:
Desc TVD
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The Thread Target window enables you to select which targets you want
to thread. The targets displayed are those selected by the current
wellpath.
To thread targets:
1. Select a number of targets to thread by picking from the Add To List
button, (or double-click on them); you can remove them using the
Remove From list button.
2. Select the order in which the targets are to be threaded by choosing
from Sort Targets:
Choose... To...
Displacement Hit the targets in order of increasing horizontal
displacement.
Descending First hit the shallowest target, then the next deepest, and
so on.
Target Sort Methods
Target Thread Methods:
• Curve Only
• Curve-Hold
• Optimum Align
• Straight
• Least Turn
COMPASS tries to use this dogleg if
possible, otherwise it is incremental
automatically until a solution is
achieved through all targets.
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3. Select the threading method from the list:
4. Specify the Dogleg to apply - Enter the Dogleg you require for the
selected curve type (does not apply to curve only). If the dogleg
severity is insufficient, then a better dogleg is suggested and the
path computed. If you’re not sure what dogleg to use, then leave the
value set to a very small value (e.g., 0.1º/100ft) and COMPASS
works out the doglegs. Note: if 0º/100ft is specified, COMPASS
often defaults to 5º/100ft dogleg between each target. If this is the
case, try decreasing the dogleg and re-calculating to see if this is
indeed the minimum dogleg that can be used.
After generating a plan using this method, each set of plan sections
between targets is linked to a particular planning method—not the
Ascending Hit the deepest target first, then the second deepest, etc.
Name Hits the targets in the order specified in the thread target
list.
Choose... To...
Curve Only Add on one curve section per target. COMPASS
computes the dogleg severity required to hit the next
target with one circular curve.
Curve Hold Adds two sections per target. Specify the Dogleg
Severity and COMPASS computes the initial toolface
angle and length of hold section required to hit each
target in turn.
Optimum Align Adds three sections per target a curve, hold, and curve,
and connects the last two targets via a straight line. (See
Optimum Align planning method.) You need to specify
the dogleg severity to make the turns.
Straight Line Finds the best straight line to thread through the targets.
It uses optimum align to get to the first target. Normally
the line starts and ends with the vertical depth of the first
and last target, but if the targets are near horizontal or
'sort by displacement' is chosen, then the line is limited
by displacement. The best-fit line is weighted to hit
targets with smaller dimensions. The best-fit line does
not necessarily pass through each of the target
dimensions; a message is reported if a target has been
missed.
Least Turn Calculates a trajectory with the least amount of turn
through the targets
Choose... To...
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Thread Target planning method itself. For example, the Thread Targets
solution can consist of Optimum Align sections and Dogleg-Toolface
curves. After pressing OK in Thread Targets, double-clicking on any of
the constructed sections would not launch the Thread Target drop-down
layout, but the planning method drop-down linked to that section itself.
Nudge
Nudge contains plan methods for horizontal or dipping formation
targets. It is also useful for inserting nudge sections into a plan to assist
with anticollision.
Simple Projection - This computes the trajectory to land at a vector at a
specified TVD, MD or Dogleg.
1. Enter the required Inclination and Azimuth
2. Enter one other parameter from MD, TVD or DLS.The other
parameters in the curve will be computed.
Project Ahead
Click the Project Ahead button to access the Project To dialog.
Project ahead is the process of looking forward from the current bit
depth to see if the path is heading towards the target. If the Wellbore is
not on course, Project Ahead can be used to determine the correction
necessary to get back on the plan or to go directly to the target. The
projection is made from the last observation in the open survey, plus the
initial-hold length. Should stations be added to the survey, the projection
recalculates from the end of these stations. If anticollision is being used,
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then the projection will be included in the anti-collision scan.The results
are for information only, and are not added to the plan.
Applied Walk Rates
With non-controllable rotary BHAs and rock bits, there is a tendency for
the hole azimuth to drift to the right (and sometimes the left); this is
known as ‘walk.’ After a few wells have been drilled in the area, you
should know roughly how much correction or lead azimuth to apply to
hit the target. Different amounts of walk are associated with different
formations, which can be defined by vertical depth.
Click Project to Target, Plan or Formation to
specify the required location and COMPASS
computes the trajectory changes using one of
the trajectory types. If the current Wellbore has
a principal plan, the actions required to return
to the plan will be indicated. This will also work
for dipping formations.
Click User Defined Projection,
Curve Only to specify the
projection distance to a MD or
TVD as well as the curve rates
and COMPASS computes the
new location.
Select Target,
Formation, or Plan
to project to.
Click Calculate to calculate
the projection. The
Projection Steps will be
displayed.
Select the method
you want to use.
Refer to the online
help for more
information on the
methods.
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If the wellpath is properly led, steering should not be required, as the
natural walk tendency brings the wellpath into the target. If walk is not
included in the design—that is, if the wellpath is planned as tangent
sections between targets—frequent steering could result as the well is
corrected to counteract the natural walk tendency.
To apply walk rates to a plan with straight sections defined:
1. Using one of the 2D planning tools for Slant or S-Well, plan to one
target that has been created in the target editor.
2. Click in the toolbar and enter a number of walk rates in the
grid, and the TVD's where you anticipate the drift begins. Note that
a positive walk is to the right, negative walk is to the left.
3. Click OK or press ENTER to apply the walk rates. COMPASS
modifies the well plan by adding new sections at walk horizons and
uses the first target in the plan as the walk target. It only applies
walk to straight sections. Should you modify a walked plan using
another planning method, you won’t be able to restore the original
un-walked plan.
Enter the TVD of the start
of a known walk section.
This may correspond to a
formation top, change in
lithology, or entry into a
geological structure.
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Using the Plan Optimiser
The Plan Optimiser is designed to help you optimize the plan geometry
for mechanical or anticollision conditions. It contains the means to cycle
various plan constraints and then run the trajectory through torque-drag
analysis. Each result is examined for the maximum torque, tension,
buckling, side force, and fatigue condition relative to the pipe limit for
this condition. The optimum solution can be based on your preference
or optimized to be the lowest stress condition meeting all of the criteria.
The mechanical results can be reported, graphed, or the trajectory fed
back into the current plan for anti-collision. The optimizer works on
most common plan types, though it is most useful for plans that have
dogleg/build rates and kick-off or hold sections. You can also choose to
vary drill string or BHA type and length.
Here are the plan methods that are supported:
� Kick-off depths, by tie-on depth or hold section.
� Slant Wells and S-Wells, where dogleg is specified.
� 3D Curve Hold (DT or BT) and Optimum align (by doglegs).
� Straight sections at end of the plan or final projections.
Other plan methods can be in the plan, but their chosen parameters are
not changed.
The first occurrence of the plan type is the one that is manipulated. For
example if a thread target method is chosen to hit multiple targets, then
it is the first Optimum-Align or Curve-Hold that is changed and the
others are not varied but are recalculated.
The grid is used to display one or a number of possible solutions when
you click Calculate. The grid is not available for edit, though there are
a number of actions available through the grid. Selecting a line loads the
parameters from that line into the plan, analyses it and updates the plan
and views. Pressing the top label button of a number column sorts the
list, showing the minimum first of this parameter. Pressing the top label
button of an error column (ER or Error Message) removes those lines
with errors from the list. It helps to do this before sorting.
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Torque and Drag Calculations
The Torque Drag calculations used in this simulation are standard 'soft
string,' and have been optimized for speed. They are run at the sample
interval used for the plan survey; this is +/- 100' or shorter for more
severe doglegs. It is an approximation of the model used for
WELLPLAN for Windows, and should not be used as a substitute where
more accurate results are required. There are a number of differences:
� Tortuosity is introduced directly into the side force calculation
rather than changing the survey.
� Sinusoidal Buckling is computed using joint diameter for hole
clearance.
� Friction is split into radial (torque) and along hole (sliding)
components.
� Analysis includes overpull to determine maximum for stuck/jarring
loads.
The numbers for the torque, tension, fatigue, and buckle mean the
following:
Value = Tubular Load Limit / Actual Max Load.
So, if a column is selected, then the maximum value is listed at the top,
which is, in fact, best limit/load ratio. It reports the maximum value for
the load in the whole string for each of the four load cases. Numbers
greater than one mean the limit has not been reached by any actual load.
It is a bit like casing design safety factors. The following values could
be used for the numbers:
� Tension = Pipe tensile yield/Actual max tension
� Torque = Pipe joint make-up torque/Actual max torque
� Buckling = Pipe Critical Buckling Force/Actual Max pipe
compressive axial force
� Fatigue = Fatigue stress limit/Actual max bending stress 25000 psi
for DP, 18000 for HWDP and 13000 for casing or collars. The
bending stress is compensated for tension
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Load Cases
This simulation uses five load cases to generate ranges of forces on the
drill string.
� On-bottom drilling/rotating using weight on bit and rotary torque.
The drilling case can include sliding friction when steering with a
motor.
� Off-bottom rotating the drill string with no bit weight and no bit
torque.
� Pick-up (pulling out of hole) uses +ve drag forces only and no
torque.
� Slack-off (running into hole) uses -ve drag forces only and no
torque.
� Overpull uses defined stuck-force plus +ve drag forces; It assumes
you are pulling pipe and encounter a resistance force at the bit (and
are not rotating).
Note: Compound Friction
These do not model compound friction, such as Top Drive rotating while running
pipe. If compound load analysis is required to model actual pipe angular velocity,
you should use WELLPLAN Torque/Drag software instead.
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Plan Optimizer Editor
The following graphic depicts the Plan Optimizer Editor.
To start the Plan Optimiser a plan must be open. There is an associated
Plan Optimiser View that shows the torque-drag and side-force charts
for the current plan. Closing the plan gets rid of them all; closing the
optimiser closes itself and the optimiser view only.
Plan Editor Interaction
You may return to the plan editor and manipulate the plan when the Plan
Optimizer is active. To operate the plan optimizer, just calculate a plan
in the Plan Editor, then click the Optimizer button.
Results Grid displays
Torque/Drag and Cost
for different calculated
planned trajectories
within user-entered
planning constraints;
enables user to compare
results.
Torque/Drag ratios compare worst
case string load against string rating.
Can order plans from best to worst.Error Type column
details reason behind
plan row failure.
Error column flags
which plans fail
Torque/Drag or
A Single Plan trajectory can be
optimized within the ranges of
entered constraints in terms of
Costs, Mechanical Limitations or
Anti-Collision constraints.
A Number of Plans can be
calculated for each one of the
ranged parameters. Results for
all plans are then displayed in
the results grid.
Tabs enable user to
define precise or
range of values for
different types of
planning parameters.
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Once the plan changes, the Optimizer will re-calculate torque-drag and
update the graphs (and give an error message if a mechanical constraint
is exceeded). When you close the Optimizer, you are given the option
"Do wish to update the plan with the optimized data?", select Yes if you
wish to modify the plan or No if you wish to retain the original plan and
discard the plan chosen by the Optimizer.
Data Context
The Optimiser data is saved in a file with the well so all optimizations
on the well uses the same data. The file is called W*.WOP where * is
the well number, and it is stored in the COMPASS\OUTPUT directory.
Using the Optimizer Tabs
There are eight tabs, containing a number of entry fields. Some tabs
have one or two Use Range check boxes indicating a parameter that can
be cycled or optimized. Depending on the plan methods used, some of
the options may not become available. Parameters that can be varied
have a minimum, maximum, and step field. The minimum field contains
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the default value for this parameter if is not to be cycled, and is the
minimum value for the cycling range when the check box is set.
Profile Tab
The profiles tab contains the plan variables from the Plan Editor. In the
Optimizer you can select any number of these user-entered cells to run
a range through or optimize for.
Drill String Tab
The drill string tab is the entry point for the work string for the torque
drag & hydraulics analysis. You can enter up to six sections by name
and length. The catalog items are taken from the 'tubes.csv' file. There
are no entries for minor BHA items like bits, motors, jars, subs or
stabilizers.
Check the Use box to
indicate the associated
variable should be used
in range analysis.
Specify the range to be used
in the analysis.
Select Component from drop-
down list. Enter the components
from the top down.The total length of the
component section.
The top item has its
length computed from
the total depth of the
design, so there is no
need to be exact here.
The bit/shoe is
assumed to be at the
total depth.
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Open Hole Tab
The open hole and cased hole tabs allow the setting of some of the hole
section conditions.
Cased Hole Tab
The cased hole tab allow the setting of conditions in cased hole.
Specify the depth of the bit; if this is set
to zero, the bit is assumed to be at the
TD of the plan.
The Hole Diameter is the
bit diameter.
Tortuosity is a measure of the
roughness of the hole when drilled,
in terms of dogleg severity.
Example values for open hole are
0.25 for hole drilled mainly rotating,
and 1.0 for hole drilled while
steering (in degrees/100' or 30m).
Friction Factor is the component of friction
affecting the torque and drag results. Example
values for oil-based mud is 0.21 and for water-
based mud, 0.29.
Use the Max Angle check box to define a
maximum allowable hole angle in this cased
hole (allows for borehole stability or running of
wireline tools.
Specify the depth of the casing
shoe. The location is interpolated
from the plan. If the casing depth is
zero, then the open hole values
are taken to surface.
Specify the inside
diameter of the casing.
Tortuosity is a measure of the
roughness of the casing in terms
of dogleg severity. Example
values for cased hole are 0.25 for
smooth hole, and 0.5 for rough
hole (in deg/100' or 30m).
Use the Max Angle check box to define a
maximum allowable hole angle in this cased hole
(allows for borehole stability or running of wireline
tools.
This is the component of friction affecting the
torque and drag results; the value is unitless.
Example values for oil-based mud is 0.17, for
water-based mud, 0.24, and for brine, 0.30.
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Drilling Tab
This tab contains common drilling parameters for the simulations.
Cost Tab
These parameters are used in the time and cost estimates.
This is the assumed torque required to drive the bit
and/or mud motor. The Torque on Bit and Weight
on Bit parameters define the load acting on the
bottom of the string. These loads are used as the
starting conditions for the soft string Torque/Drag
calculations.
Mud Weight is the mud density of the
drilling fluid, assumed constant inside
and outside the pipe.
Overpull Weight is the allowable pulling
tension at the bit used to trip jars or free
stuck pipe. The overpull load condition is
usually the case for maximum tension and
includes the drag forces when pulling out of
hole.
Check Use Sliding Drilling to include
wellbore drag in the drilling load
case. Otherwise the string is set to
rotating and no string drag is
incurred. You will notice that buckling
becomes much less of a problem
when the string is rotating.
Enter the total flow area, PV, and YP of the bit
be used for determining hydraulic limits.
Operating Day Rate is the total cost
per day for this drilling rig, plus
services.
Production Casing Cost is the
cost of production casing for cased
hole section in terms of cost/length.
Liner Casing Cost is the cost of the
liner to complete the open hole
section in terms of cost/length.Enter rates of penetration for rotating or
steering for the vertical depths to be
encountered. This table is used to
determine time costs for drilling the
directional plan.
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Limits Tab
Anti-Collision
Check this option to configure the analysis to determine whether
plans collide with offset wells. Define an anti-collision boundary
area around the planned wellbores by entering a minimum range
and depth ratio in terms of x/1000. This computation is only
possible if you have open an anti-collision graph (ladder, traveling
cylinder) with the required offset wells. Note that having a large
number of offset wells slows down the Optimiser.Tension Safety Factor
This is the allowance for torque or tension yield. For example, 1.25
is 80% of yield, or over-torquing. A value less than 1 is not
accepted.Side Force Limit
This is the threshold before it is assumed that tool joints cause
casing wear or keyseating. This constraint is optional; toggle on the
check box to use the constraint.Maximum number of trials
This is the maximum number of option combinations performed
when you click the Calculate button. This feature prevents the
Optimiser from spending a large amount of time computing several
thousand plans when you enter a wide range of combinations. If you
have a fast PC, you can set this value to as much as 2000, although
a value of 100-500 is more common.
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Offsets Tab
The offsets tab allows for offset wells to be analyzed as redrill
candidates. Once an initial plan is designed, plans can be generated from
these offset wells using a sidetrack depth range specified in the grid.
When calculated, a list of the computed trajectories for each of the
offsets selected will be displayed in the results grid. These can then be
sorted by cost or any of the other engineering constraints to obtain the
best candidtate for re-entry.
Once the results are displayed in the grid, the desired plan can be
selected. If the optimizer is closed down with a plan selected, it will
create the plan in the new wellbore automatically and open it.
Wellbore
Displays the list of offset designs that were selected prior to
entering the wellpath optimizer.Use AC
Use the offset design for consideration anti-collision. These will
only be used if the anticollision limit was checked in the Limits tab.Use ST
Check this column for any offset design that will be considered as a
candidate for re-entry.ST min
Enter the minimum sidetrack depth for the offset wells selected as
re-entry candidtates.ST max
Enter the maximum sidetrack depth for the offset wells selected as
re-entry candidates.Step
Enter the sidetrack depth increment for which the plans will be
calculated between ST min and ST max.
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Buttons and other Features
Calculate or Optimize?
Consider the difference between the Calculate and the Optimize
buttons:
� The Calculate button runs every possible scenario within each
range that has been chosen, and lists them in the Grid. Click on the
columns or lines and look into the Plan Editor or views to decide
which result is best. For instance, if the following are chosen: a
kick-off depth range of 1000 to 2000, at steps of 100 and a build
rate range of 1 to 2 deg/100 at a step of 0.1, then Calculate runs
11x11=121 simulations. There is a default limit on the number of
simulations in the Options tab, but it can be increased.
� The Minimize button, on the other hand, calculates only the best
possible solution. Its optimum criteria is the minimum of the four
limit ratios (i.e., the load case closest to the limit). It then chooses
the solution that, through all the ranges defined, has the maximum
limit (in other words, is the least loaded string). The optimized
solution allows a user to scan more variables at one time than the
Calculate option.’
Which you choose depends on how constrained the problem is. If the
sheet is completely clean, then the Optimiser is more useful. If the
drilling situation is fairly well defined, but can vary two or three options
(like KOP, DLS), then the Calculate option is adequate.
An additional consideration would be that the optimized solution hunts
using any variable within the Min/Max range without the step value,
while the Calculate option uses the step sizes.
Notepad
To access, click the button in the Optimizer toolbar to access
the Optimizer Notepad.
Takes the currently selected analysis and reports the torque/drag
results to Windows Notepad. This file is tab separated and can be
loaded into a spreadsheet for reporting. If no line is selected in the
results grid, then the contents of the grid are reported to the notepad.
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The contents of the standard report are explained below.
• DEPTH - Measured depth of this point in the drill string
• PIPE# - Reference number of pipe section, (1=Collar, 2=BHA,
3=Pipe)
• HOLE# - Reference number of hole section, (1 = Cased, 2 =
Open hole)
• WBTRQ - Torque when drilling
• FHTRQ - Torque when rotating off bottom
• MAXTRQ - Make-up torque of pipe, used as limit
• WBWT - String weight/tension when drilling
• PUWT - Weight when picking-up
• SOWT - Weight when slacking-off
• FHWT - Free hanging weight (rotating off bottom)
• OPWT - Weight when pulling with overpull at the bit
• HELB - Helical Buckling limit
• WTMAX - Tension limit of tubular
• BSTR - Bending stress
• BMAX - Maximum bending stress (fatigue endurance limit)
• SFOR - Lateral side force (+is up and - is down/lowside)
• SFMAX - Limit on side force for keyseating/casing wear
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Grid Manipulations
The grid is used to display one or a number of possible solutions when
Calculate is pressed. The grid is not available for edit, although there
are a number of actions available through the grid.
� Selecting a line loads the parameters from that line into the plan,
analyses it, and updates the plan and views.
� Pressing the top label button of a number column sorts the list
showing the minimum first of this parameter.
� Pressing the top label button of an error column (ER or Error
Message) removes those lines with errors from the list. It helps to
do this before sorting.
Grid Columns
The grid columns contain salient parameters for each run of the
analysis.
This
Parameter... Indicates...
ER Whether this analysis was successful. It shows a cross if an
error or failure has happened.
Error Type The type of error (geometry) or limit condition that has
been exceeded.
KOP The Depth of the kick-off from vertical or side-track.
DLS1 The Dogleg Severity of the first build/turn.
DLS2 The Dogleg Severity of the second build/turn.
Time The time needed for directional drilling this well.
Cost The cost incremental in the directional phase of this well.
Torque Maximum ratio value of make-up torque/string torque for
the pipe in this analysis.
Tension Maximum ratio value of yield tension/string tension for the
pipe in this analysis.
Buckle Maximum ratio value of helical buckling limit/string
compression for the pipe in this analysis.
Fatigue Maximum ratio value of fatigue limit/bending stress for the
pipe in this analysis (tension corrected).
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Tubular Catalog
The tubular catalog used for the optimiser is called TUBES.CSV and is
located in the COMPASS\CONFIG directory. It can be loaded into a
spreadsheet and edited. The entries are grouped by type and listed within
each group in order of size, then yield strength. This order should be
maintained because the logic of the optimiser depends on it. The units
are API and not changeable. The file contains a number of columns as
follows:
� Name - used for the selection and reporting
� Pipe body outside diameter (in)
� Pipe body inside diameter (in)
� Tool Joint outside diameter (in)
� Pipe weight per length (actual) (lbf/ft)
� Tensile Yield strength (lbf)
� Make-up Torque (lbf.ft)
� Fatigue Strength (psi)
� Pipe Joint Length (ft)
� Tubular Type (1-4) 1= Drill Pipe, 2=Drill Collar, 3=HWDP,
4=Casing
� Material Type (1-4) 1= Steel, 2= Aluminium, 3=BeCu,
4=Titanium)
Drill String The Drill Pipe name from the catalog.
BHA Bottomhole assembly tubular type from the catalog.
Drill String The Drill Pipe name from the catalog.
BHA Bottomhole assembly tubular type from the catalog.
Start NS Surface location North coordinate.
Start EW Surface location East coordinate.
BHA Length Bottomhole assembly length.
Hold Length Length of the final hold section in the plan.
Tangent Angle The intermediate hold angle of the plan (2D plans).
Final Angle The angle of the plan at the target (2D plans).
This
Parameter... Indicates...
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Plan Optimizer Viewer
The following graphic depicts the Plan Optimizer Graphics for extended
Build-Hold-Build-Hold Sub-Horizontal Plan:
The plan optimizer graph is a plot of the torque, tension, and side forces
on the currently selected plan. The Viewer appears when the Plan
Optimiser form is called from the Plan Editor. It can be closed without
closing the editor. The viewer is intended to provided a visual
representation of how close the currently selected plan is approaching
any mechanical constraints, such as contact force limit, API tensile
yield, or make up torque limit. This graph is not intended to be a
replacement for a full torque/drag analysis.
The Graphs
A view of torque drag results in graphical form is given when the
optimiser is open. It updates when any single analysis is run, or a line
is selected from the grid. There are three graphs; each single graph
can be altered by clicking in its axis area.
Measured Depth against Torque
This graph has a number of lines:
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• On-bottom torque (blue)
• Off-bottom torque (green)
• Make-Up Torque limit (red)
Measured Depth against Tension/Compression
The tension graph has a number of lines:
• On Bottom Drilling (blue)
• Off Bottom Rotating (green)
• Pick -up weight
• Slack-off weight
• Overpull weight (yellow)
• Helical Buckling limit in compression (red)
• Pipe yield limit in tension (red)
Vertical Depth against Vertical Section with Side Force
Commonly known as the hairy wellpath plot, this graph is good for
visualizing the points in the wellbore profile where there is
maximum contact force. The strike marks indicate the side force per
tool joint. Marks on the lowside of the wellpath indicate gravity
forces. Marks on the highside of the wellpath indicate tension in
dogleg forces.
This graph includes:
• The wellpath vertical section line (yellow)
• Side forces adjacent to the wellpath (blue)
• Side force limit lines where requested (red)
• Wellpath labels every 1000' or 500m MD.
• A casing shoe marker to indicate the Last Casing depth.
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The red side force limit lines can be turned on/off by choosing the
'use side force limit' in the Options tab of the Wellpath Optimiser.
Bubble View
This plot will display a bubble plot of the first two options checked
in the profile tab. The most useful application of this view is when
N/S and E/W coordinates are sensitized for a given target TVD. In
this case, the user can essentially created a drilling limits plot
showing the reachable area for a given TVD
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Planning and Anti-Collision
The Anti-Collision module is designed to use the ‘active’ path as the
reference wellpath when performing an anti-collision scan against offset
wells. If a plan is open, the anti-collision module scans down the plan.
This is a very constructive feature, in that plans can be designed to
adhere to a company’s anti-collision policy as defined within Company
Setup. Changes to a planned trajectory automatically results in all anti-
collision graphs or wallplots being updated automatically. Any reports
that are open would need to be regenerated.
The following graphic depicts the 3D Proximity Graph with a planned
Sidetrack being scanned against an offset slant well:
The example above displays a planned sidetrack well scanning against
another wellpath in the same site. In this example there is a considerable
collision risk, so this sidetrack trajectory has to be changed in order for
the plan to be approved prior to drilling.
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Chapter 5: Planning Module
Planning Reports
Having designed a wellpath trajectory, an engineer must be able to
communicate that trajectory to other colleagues across disciplines in
order for it to be assessed. COMPASS provides a number of methods to
accomplish this, using Formatted Reports, hard copy output of the live
graphs or multi-sized wallplots, and user configurable export file
formats.
Planning Reports is accessed from the Planning menu if a Plan is open,
or from the main COMPASS toolbar .
The following graphic depicts the Planning Reports Window:
The Select Report area
contains a group of check
boxes that you select to filter
the list of reports that display
in the table.
The Reference Level area displays reference level
information that determines what reports are available
for selection.
Select (by highlighting) the
report you want.
Click:
Preview to preview the report on the screen.
File to generate the report to a file.
Print to print a hard copy of the report.
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214 COMPASS Training Manual Landmark
Planning Report Options
The Report Options dialog is displayed when you select the Preview,
File, or Print buttons on the Report dialog if the report contains survey
data.
If the Interpolate box is checked, the Interval field is
active and you can set the depth interval at which to
interpolate survey stations. Checking this box also
activates the Specify Depths by radio buttons, which
you can use to interpolate by MD or TVD.
Check the Range box to set a
specific depth range to be
included in the report. The From
and To fields become active, and
you enter a numeric value in
each to set the range.
Check Include station at end to
include the end station information.
Select the options you want included on the
report.
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Chapter
Anti-Collision Module
Overview
The Anti-Collision module provides the most critical functionality in
COMPASS affecting drilling safety and operator costs.
� Safety in terms of collision avoidance and drilling close rules.
� Cost in terms of the potential risk of a wellpath interfering with one
or more offset wells, requiring decisions to be made on drilling or
production restrictions.
Results from the anti-collision module are used directly to make these
types of decisions.
Companies differ in their approach to anti-collision scanning. However,
COMPASS was designed to accommodate most commonly used
methods. Company anti-collision policy is usually set out in a corporate
drilling procedures manual. This may be your own company or a client.
COMPASS therefore sets anti-collision parameters at the Company
Setup level, which is typically locked and therefore protected from day-
to-day users.
COMPASS enables you to perform an anti-collision scan down any
open design, or survey, including project ahead sections constructed
from within the Survey or Plan Editors. The scan can be conducted
against any number of designs within the same well, site, or project.
Additionally the scan can be applied against nearby designs located in
other projects or companies. If used correctly, COMPASS is capable of
detecting a collision risk from a reference well, including all offset well
trajectories defined in the COMPASS database. Results are available on
a variety of plots and reports.
6
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216 COMPASS Training Manual Landmark
Specifying AntiCollision Analysis Parameters
The COMPASS anti-collision module is defined by four concepts:
The Data Structure section of this manual described how the Company
Properties dialog is used within COMPASS to apply company anti-
collision policies so that all anti-collision results are consistent within
the same rules and assumptions defined by the chosen models. It is very
important that companies recognize the importance of ensuring that
COMPASS data is distributed to all sites with exactly the same
Company Properties, and that it is generally kept locked to prevent the
setups being changed.
Use File > Properties > Company > Properties > Anticollision tab to
specify the anticollision analysis properties.
This concept... Determines...
Error System How positional uncertainty is calculated
Scan Method How wellpath separation is calculated
Error Surface How separation factor is calculated
Warning Type What criteria is used to issue warnings
The Error System determines how the
positional uncertainty is calculated.
Refer to “Error Systems” on page 217.
The Error Surface determines how the
separation factor is calculated. Refer to
“Error Surfaces” on page 225.
The Warning Type
determines the
criteria used to
issue warnings.
Refer to “Warning
Types” on
page 224.
The Scan Method
determines how the
wellpath separation is
calculated. Refer to “Scan
Methods” on page 219.
This grid is used to define
a number of anticollision
warning criteria. The
columns and labels that
appear on this dialog
depend on which Warning
Type is chosen.
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Chapter 6: Anti-Collision Module
Error Systems
Prediction of wellpath location uncertainty is fundamental to safe and
cost-effective well design. Wellpath trajectory is only imperfectly
represented by survey measurement and trajectory calculations.
Because survey instruments are not 100% accurate, errors can occur in
calculated borehole trajectory. Uncertainty envelopes for wellpath
trajectory are calculated based on survey tool error models, and provide
the minimum standoff distance to prevent wellbore collisions.
Uncertainty estimates range from field-based rules of thumb to strict
analytical and statistical methods.
COMPASS uses the ISCWSA or Cone of Error survey tool error
models.
ISCWSA
The ISCWSA committee’s remit was to “produce and maintain
standards for the Industry relating to wellbore survey accuracy.” A
number of companies supplied resources (Anadrill, BP, BGS, Gyrodata,
Halliburton IKU, INTEQ, Landmark, Norsk Hydro, Saga, Scientific
Drilling, Shell, Sperry Sun, Sysdrill, Statoil, Tensor) but the main
working group was formed by BP, INTEQ, Statoil and Sysdrill.
The committee recognized that directional drilling requirements have
moved on from the 1970’s when the Systematic Ellipse model was
constructed. Modern needs require smaller geological targets to be hit,
often drilled in mature fields with a large number of nearby wellpaths.
The simplistic WdW model could not handle such strict requirements
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218 COMPASS Training Manual Landmark
and accurately model additional performance parameters measured
from vendor survey tools.
A number of other factors provided the incentive for an alternative
industry model to be developed:
• risk-based approaches to collision avoidance and target hitting
required positional uncertainty to be associated with confidence
levels, a term only implied with the WdW model
• changed relationships between operators, directional drilling,
and survey companies forced all parties to share information on
tool performance
Dynamic Number of Error Sources (Terms), each defined by: •Name e.g. Accelerometer Bias•Vector direction for error source
•Azimuth•Depth•Inclination•Lateral•Misalignment•Inertial•Bias
•Value error value for the source of error •Tie-On determines how an error source is tied onto sources:
•Random•Systematic•Well•Global
Formula weighting for each error term e.g. ASX
Range inclination range for error term
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Chapter 6: Anti-Collision Module
• drilling and geoscience software enabled more sophisticated tool
error models to be incorporated, with results that could be
viewed in 3D earth model visualizations
• survey program designs to hit smaller drillers targets dictated by
tool error models and smaller geological targets
As described in the Survey Tool Editor section of this manual, the
ISCWSA committee designed a dynamic survey instrument error model
specifically for solid state magnetic instruments (e.g., MWD and EMS).
The resultant model is described in a paper published by H.Williamson
“Accuracy Prediction for Directional MWD” by Hugh Williamson as
SPE56702. Essentially, the model enables an operator or survey
contractor to define a dynamic number of parameters or error terms
appropriate for a survey instrument.
Cone or Error
This model assumes an error sphere around each survey observation.
The model is empirical and is based on field or test observation
comparisons of bottom hole positions computed from various
instruments. The size of the sphere is computed as follows.
Radius of sphere around previous observation + MD interval x survey
tool error coefficient / 1000.
The starting error around the wellbore is the well error plus the top
borehole radius. The survey tool error coefficient depends on the current
tool inclination and the values contained in the Inc/Error grid for that
survey tool.
Scan Methods
The purpose of an anti-collision scan is to calculate the distance from the
scanning point on a reference well to the ‘closest’ point on an offset
well. This distance is known as the center-to-center distance, or wellpath
separation. Different scan methods determine different separation
distances because each technique uses a different algorithm and may not
find the same closest point as another technique.
Four Scan Methods are available in COMPASS:
� Closest Approach 3D
� Traveling Cylinder
� Horizontal Plane
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220 COMPASS Training Manual Landmark
� Trav. Cylinder North
In the following explanations the reference wellpath is the wellpath
being planned, drilled or surveyed. You check the distance from the
reference wellpath to any number of offset wellpaths. COMPASS scans
down the reference wellpath at intervals defined in the Interpolation
Interval, and computes the distance to the offset wellpaths using one of
the following scan methods.
3D Closest Approach
At each MD interval on the reference wellpath, COMPASS computes
the distance to the closest point on the offset wellpath. At some scanning
depth on our reference wellpath, imagine an expanding spheroid. The
minimum separation occurs when the surface of the spheroid initially
touches the offset wellpath; separation is the radius of the spheroid.
Because the offset wellpath is now at a tangent to spheroid, the line of
closest approach is perpendicular to our offset wellpath.
The following graphics display the 3D Closest Approach Scan Method
(left) and the Traveling Cylinder method (right):
Traveling Cylinder
This scan method uses a plane perpendicular to the reference wellpath
and intercepting offset wellpaths as they cut through the plane. The
surface resembles a cylinder with the size of the maximum scan radius.
The traveling cylinders method computes distance from the offset
wellpath stations back to the reference wellpath. The benefit of this
Offset Well Reference Well
3D
Offset Well Reference Well
Orthogona
l
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Chapter 6: Anti-Collision Module
method is that intercepts are detected even when the wellpaths are
approaching at a perpendicular. In this case, there may be more than one
point in the TC plane for the same depth on the reference.
Depths are interpolated on the offset wellpaths, resulting in irregular
depths on the reference wellpath. Therefore, the 3D anticollision view
and traveling cylinders depth slice option are not possible with this
method, because they rely on regular depths on the reference.
Trav Cylinder North
This scan method uses the same perpendicular plane as the Traveling
Cylinder scan method, but toolface orientation from reference to offset
is added to current Wellbore direction. The traveling cylinder plot is
oriented to Map North when the reference well is at low angles.
Toolface angle to an offset well is then reported as the angle from the
high-side of your current Wellbore + the azimuth of your current
Wellbore. This method avoids the confusion in the Traveling Cylinders
plot caused by large changes in toolface angle when kicking-off from
vertical.
Horizontal Plane
The Horizontal Plane scan method calculates the horizontal distance
from the reference wellpath to the offset wellpath. It is similar to the
traveling Cylinder method, except that the cylinder expands
horizontally irrespective of the wellbore direction. This method is not
recommended for horizontal wells that it might miss and directional
wells where it might provide late warnings, as when the well does
approach, it does so very quickly. It is in COMPASS, but don’t use it.
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The following graphic displays the Horizontal Scan Method:
Comparing the Scan Methods
The most important difference in the methods is that they are all capable
of determining a different closest point. It is for this reason alone that
Scan Method should be defined within a company and locked, so that all
anti-collision results can be compared on the same basis.
The following diagram highlights the differences using the example
above. From the same reference well scan point, the different methods
have all found a different closest point, with different values of
calculated wellpath separation.
Offset Well Reference Well
Horizontal
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Chapter 6: Anti-Collision Module
When comparing scan methods, assess the advantages and
disadvantages of each technique.
Traveling Cylinder Scan and Near-Perpendicular Intersections
The primary deficiency with the traditional traveling cylinder method is
that it can miss near perpendicular intersections if the scan interpolation
interval is large. The following graphic depicts the problem:
On the graph above, E4-S0 (right hand side) is the reference well being
scanned down. A2-S0 is the offset well. The graph displays a depth slice
that represents the orientation of the traveling cylinder at its scanning
point. As the traveling cylinder scans down E4-S0, it misses the nearby
A2-S0 well and finds a ‘closest point’ some distance up A2-S0 away
from the critical area. Even with the interpolation interval set at 25 ft.,
the A2-S0 well is missed entirely.
E4-S0 Reference Wellpath
A2-S0 Reference Wellpath
Scanning Point
Traveling Cylinder Scan calculated closest point from
E4-S0 scan point to A2-S0:
— C-C Separation = 4967.40 ft
— Ratio Factor = 47.57
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Warning Types
When we scan a wellpath or plan against other wellpaths, we want the
program to report only those wellpaths that pose a collision risk. To
include wellpath positional uncertainty in the assessment of collision
risk, COMPASS can report separation factors or assess against risk-
based rules or depth ratios.
Error Ratio
Also known as ratio factor, error ratio is a value that includes center-to-
center separation and positional uncertainty, and can be modified to
include casing diameters.
The following graphic depicts the Error Ratio Method and Example
Results:
As described in Company Properties, COMPASS enables multiple ratio
factor warning levels to be defined, and a given warning or action to be
taken if such a level is exceeded. These warning levels appear in the
anti-collision report and in some of the anti-collision graphs in the form
of levels and color-shaded lines.
Error Ratio > 1
Error Ratio = 1
Error Ratio < 1
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Chapter 6: Anti-Collision Module
Depth Ratio
Will form an envelope about the wellbore representing the minimum
separation, with the ratio of depth increasing until Max Radius is
reached.
A ratio of 0.01 with a maximum radius of 10m means that the minimum
allowable separation would consist of a cone expanding at 10m per
1000m, reaching a maximum of 10m at 1000m from the start depth.
After 1000m MD, the minimum separation surface would represent a
cylinder about the wellpath.
Rules Based
Will use a probability of intercept to evaluate risk. A ratio of 0.01 means
there is one chance in 100 wells drilled of intercepting an offset
wellbore. The warning grid in Company Properties will contain all of
the possible rules that may be assigned to a wellpath. The first row in the
grid will be the company default rule. That means when a wellpath is
selected for anti-collision, this rule is automatically applied to that
wellpath. Other rules have to be assigned directly in the Offset Wells
dialog. A warning is given if the rule is determined to fail when
conducting the anti-collision scan.
Error Surfaces
When you select an error system, you define how wellpath position
uncertainty is calculated. When selecting a scan method, you define how
wellpath separation is computed. The error surface enables you to
choose how the radius of the error surface at the reference well scanning
point and the calculated closest point on the offset well are calculated.
The error surface choice allows the user to override the standard ellipse
to ellipse (default) ratio calculations in anti-collision, and instead uses
the largest dimension of error at a point to define a cone about the
wellpath. In most cases, this will be major axis of the ellipsoid. Using
the circular conic method is more conservative and produces lower ratio
values and hence more warnings. The separation factor calculation
includes the dimensions of the error ellipse for both reference and offset
wells. The three error surface choices are as follows:
� Elliptical Conic
� Circular Conic
� Combined Covariance
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Elliptical Conic
The standard calculation of separation factor uses ellipse radius
intersections that are determined by projecting the error surface
ellipsoids onto the center-to-center plane calculated between the
reference well scanning station and its closest point on the offset well.
This method most accurately implements the survey tool error models,
because it uses the ellipsoid geometry and orientation as calculated by
the survey tool error coefficients along the course of the wellpath.
Because the center-to-center plane can intersect the error ellipsoid at any
direction from the wellpath, the resulting radius used in the separation
factor calculation ranges from the minimum dimension of the ellipse
(minor axis) to a maximum dimension (major axis). The ellipse also has
an intermediate axis with a magnitude somewhere between the minor
and major axis dimensions. Because the error radius varies in all
directions, the calculated separation factor is generally more optimistic
when compared against the Circular Conic method.
The following graphic depicts an Error Ellipse as Intersected by Center
to Center Plane:
Circular Conic
The circular conic method uses the largest dimension (major axis) of the
error ellipsoid to define a spheroid about the wellpath. Projected down
the wellpath, this becomes a cone. Using the circular conic method is
always most conservative, because it uses the largest dimension of the
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Chapter 6: Anti-Collision Module
ellipse and therefore produces lower ratio values and hence more
warnings.
In mature areas, some companies design wellpaths by applying the
circular conic method, if possible. Should a well trajectory prove
impossible to design safely using separation factors calculated by
circular conic, the operator can then use the elliptical conic method to
evaluate how the revised separation factors meet their close rules policy.
Should elliptical conic prove safe, the operator might then decide to go
ahead and drill that plan.
The following graphic depicts a Circular Conic Error Surface:
Combined Covariance
This method combines the errors on the reference and offset by
covariance addition before any distance calculations are performed. The
error distance is then computed by the elliptical conic method on the
resulting single ellipsoid. Where Casings are included the radii are
subtracted from the center to center distance. The separation factor
derived from the combined covariance technique can be directly
R1R2
C-C Pla
ne
Major
Major
Spheroidal Projection based on Major Dimension of Error Surface Ellipsoid
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228 COMPASS Training Manual Landmark
correlated to collision risk as it represents the standard deviation value
for the ‘tail of the probability distribution’.
Including Casings
Casing dimensions can be modelled within the anti-collision radii. You
define these in the Casing Editor in order for the Anti-Collision
calculations to recognize them. The effect of including casings is to
reduce the center-to-center distance by the sum of the offset and
reference well casing radii. This models edge-to-edge distance (metal to
metal) of the casings in the calculation of separation factor. This method
assumes that casing is centered in the wellbore.
The following graphic depicts the Effect of Casings on Calculated
center-to-center Distance:
With Casing Radii
Centre to Centre Distance
Without Casing Radii
7” Liner9-5/8” Casing
12-1/4” OH 8-1/2” OH
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Chapter 6: Anti-Collision Module
Selecting Offset Designs for Anticollision Analysis
Anti-collision functionality is available under the Anti-Collision menu.
Having defined what calculation methods are used within a Company to
perform anti-collision scans down a design, survey, or project ahead
section, you next select a group of Offset Designs to scan against. Then
configure the scan using the Interpolation Interval dialog. When
performing a scan, the calculated results are available in a number of
graphs and reports.
Anti-Collision Offset Designs
To access the Anti-Collision Offset Well Selector use View > Offset
Designs or click the button on the toolbar.
In this dialog, you use a Tree Control to select offset designs. Each level
in the hierarchy (site, well, wellbore, design) has a checkbox. If a higher
level than Design is checked, all designs belonging to that level are
included.
Designs are included in the choice list to allow multiple offset tracks per
wellbore (i.e. planned and actual).
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The following graphic depicts the Offset Design Selection dialog.
Filtering
To perform a rigorous anti-collision scan, you select all wellpaths in the
current field and produce a Ladder plot or Anti-collision Report.
However, on large, multiple-site fields this can take some time to
process. A less precise but quicker and thorough method is to use the
filtering tools to pre-select only those wellpaths within a certain range
of your current wellpath.
You can filter on filtered wellpaths. For example, you can select all
wells of type PRODUCER by clicking Scan All. You can then select all
Use the Filtering options to include designs from
sites within other Projects and/or Companies
within the plot, assuming the same geodetic
system and datum is used.
Filter by
Type or
Range
enables user
to restrict
offset wells to
those of
certain types
and/or within
a given range
of current
wellpath.
Specify type
using File >
Properties >
Company >
Properties >
Wellbore
Types.
Site, Well &
Wellbore Lists
enables user to
manually select
which designs
from current
Project appear in
plot. The user can
select individual
wellbores, all
wellbores within a
well, or all
wellbores within a
site. The
technique is
simple: click on a
wellbore, well or
site to select/de-
select.
The Additional Surveys list display the surveys
contained in the current reference wellbore. You can
add surveys to the offset design list by checking the
boxes associated with each item. The chosen surveys
appear in graphs and reports.
Check Save selection to DB
to save the offset design list
with the Design.
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Producers in a range by entering a range and initial distance from
wellpath origin and clicking Scan Selected.
Specifying Anticollision Interpolation Intervals and Other Settings
The Anticollision > Settings dialog is used to set the anti-collision
interpolation interval type and the method for limiting results by
separation or ratio factor. The interpolation settings are used for all anti-
collision calculations, and also for the error ellipse report. Refer to the
online help for more information on this dialog.
Note: Filtering does not perform an anti-collision scan.
Filtering does not perform an Anti-collision Scan, it helps you select wellpaths against which to scan.
Check the Interpolate check box to interpolate
the reference Wellbore for anticollision. If
interpolate is not selected, the survey stations in
the reference Wellbore (plan or survey) are
used.
Use Scan Radius and Separation Factor to limit
the offset Wellbore data that appears in the plots and
the scan report.
Range is used to limit the depth range or the
reference design that is used for anticollision
scanning.
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Analyzing Results
Using Live Graphs
Live graphics are available to an engineer to assess anti-collision risk.
These graphs may be used concurrently so that a user can assess risk
from different perspectives. These graphs are termed ‘live’ because they
will update if any survey data or plan trajectories change.
Using the Live Graph Toolbar Buttons
The following is a list of the anticollision live graph toolbar buttons that
provide additional functionality to help assess any collision risk:
Click... To...
Graph Options: Access the Graph Options Tabs to
configure graphs and plots.
Toggle Axis Labels: Turn on or off Axis labels. This
includes the tick mark labels.
Toggle Data Labels: Turn on or off Data labels. These
include labels for depths, targets, casings, formations,
etc.
Toggle Horizontal Boundaries: Label planning
change points and project horizontal dotted line to axis
indicating point of change.
Toggle Vertical Boundaries: Label planning change
points and project vertical dotted line to axis indicating
point of change.
Toggle Targets: Show or hide targets.
Toggle Project Targets: Show the project targets. Must
have the toggled.
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Toggle Cross: Show the local point of the view. This is
also the point of rotation.
Toggle Wellbore Center: As you move along the
Wellbore, re-center the view.
Well Labels: Toggle well labels on or off.
Depth Labels: Toggle depth labels on or off.
Grid Lines: Toggle background grid lines on or off.
Casing Shoes: Turn casing points on and off. Casing
points are displayed as casing shoes on section and plan
views, and as casing tunnels on template and spider
views.
Ellipses: Plot ellipses of uncertainty on wellbores. The
ellipsoid of uncertainty is projected into the viewing
plane.
Symbols: Turn symbols on and off.
Templates: Turn on Template slots.
Rescale Axis: Rescale axis provides an expanding box
to use to select a portion of the graph. Refer to the
online help for more detail.
Zoom: Zoom in or out on the plot.
Print: Print to printer or plotter.
Click... To...
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Show Offset Designs: Include additional wells on the
plot.
Close: Close the graphic view.
Pedal: (Travelling Cylinder Plots) Show no-go areas.
The no go area is the combined ellipse size plus
additional criteria like casings. The shape may resemble
a dumbbell and is known as the pedal curve about the
combined ellipse shapes.
Shadows: (Travelling Cylinder Plots) Show error
shadows. The shadow is a line surrounding several no-
go areas for the color depth band defined in
Interpolation Setup.
Error Bars: (Ladder Plots) Click this button, and the
error bars show the edge to edge separation. The length
of the error bars is the sum of the error around current
and offset Wellbores. The distance from the bottom of
the error bars to the X-axis represents the edge to edge
distance.
Magnetic Equivalent Distance: (Ladder Plots) Show
the Magnetic Equivalent Distance. This distance is the
inverse square sum of the distances to all of the ‘drilled’
(not planned) wellbores. The line represents total
magnetic effect of several adjacent casings, as a single
distance to one cased wellbore.
Ratio Warning Levels: (Travelling Cylinder Plots,
Separation Factor Plots and Ladder Plots.)Turn off or
on the lines indicating ratio warning levels.
Depth Slice: The depth slice button will activate the
interactive travelling cylinder view.
Depth Plane: (3D Proximity View) Displays a
proximity plane at the current scan depth. The depth
plane is shown as a disc perpendicular to the reference
with the scan radius. The closest positions on the offset
Wellbores are shown as cross hairs in the well’s color.
Curtain Axis: (3D Views) Replace the north and east
walls with a vertical grid that follows the trajectory of
the Wellbore. The curtain will illustrate wells with large
changes in azimuth.
Click... To...
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Chapter 6: Anti-Collision Module
When performing an anti-collision scan, COMPASS uses the current
design’s wellpath as the reference wellpath. If a plan, survey, or project-
ahead section is open, the anti-collision module uses that instead of the
current design wellpath.
Example Anti-Collision Analysis
To describe the Anti-Collision graphics in this section of the manual, a
planned sidetrack wellpath A1-S2 designed to launch from the parent
wellpath A1-S0 at 4300 ft MD is used as an example. Note that for
actual use, COMPASS can scan any design, survey, or project ahead
section.
The plan is shown in the next diagram highlighted in green with plan
section boundaries projected vertically and horizontally. Shadows are
turned on to display where the plan launches from the parent wellpath.
If you observe the shadows, you can see where the sidetrack departs
from the parent on the horizontal and vertical projections.
All offset wells included in the scan are also portrayed. The offset wells
are located in two sites: Alpha and Echo.
Set Center: (3D Views) Use the mouse to place the
zoom center at the point on the Wellbore.
Click... To...
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The following 3D View displays a planned sidetrack (A1-S2) and offset
wells from two sites, Alpha and Echo:
Spider View
One of the traditional anti-collision graph types, a Spider Plot is a plan
view of a number of wells. Traditionally, a spider plot was easily hand
drawn by the directional driller or operations engineer as survey data
came in with measured and true vertical depths drawn adjacent to the
plotted wellpath trajectory. The spider plot displays wellpaths with East
(X-axis) against North (Y-axis).
There are two types of Spider Plot:
� Spider View—Local, which shows the data using local coordinates.
� Spider View—Map, which shows the data using map (grid)
coordinates.
Because it only portrays the horizontal projection of the wellpaths, it is
difficult to visually assess anti-collision risk, except perhaps if the TVD
labels are turned on where you might be able to see two wellpaths cross
or approach at a similar TVD.
AlphaEcho
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Viewing Casing Tunnels
If you turn on casings in the Spider and Template views, a
tunnel is drawn down the wellpath. The diameter of the tunnel is
dependent on the diameter column being filled in on the Casing
editor.
Note: Helpful Hints
• Always turn on errors to assess lateral uncertainty.
• You can use the Line Data Reader to assess TVD proximity for nearby or
overlapping wells.
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The following diagram depicts a Spider View of the planned sidetrack
well within the Alpha site in the Sample Field:
The above example shows that the planned sidetrack (A1-S2P1 in
middle) crosses the A2-S0 wellpath and approaches E4-S0. From this
simple view you can assess that A2-S0 and E4-S0 are the only wellpaths
that pose a collision risk.
The insert graphic displays just the area about the sidetrack wellpath.
TVD labels are turned on, which show that the offset wellpaths are
nearby in terms of TVD with both offset wells crossing between 5500ft
and 6000ft TVD.
Ladder View
The Ladder View plots Measured Depth of the reference well against
calculated center-to-center separation of one or more offset wells. You
use this graph to assess the true anti-collision risk of an offset well and
display center-to-center distance, magnetic interference equivalent
distance, error surface magnitudes, and ratio factor warning levels.
Sample - AlphaAll depths referenced to Sample Alpha DFE 150.0ft
West(-)/East(+) [ft]
South(-)/North(+) [ft]
-8000
-8000
-6000
-6000
-4000
-4000
-2000
-2000
0
0
2000
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4000
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6000
6000
8000
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12000
12000
14000
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16000
-6000 -6000
-4000 -4000
-2000 -2000
0 0
2000 2000
4000 4000
6000 6000
8000 8000
E4 (E4-S0) A2 (A2-S0)
C3 (C3-S0)
C5 (C5-S0)
B2 (B2-S2)B2 (B2-S1)B2 (B2-S0)
A1 (A1-S0)
E7 (E7S2)
E7 (E7S0)
E5 (E5S0)
E6 (E6S0)
E9 (E9S0)
E1 (E1S0)
A1-S2
A1-S2P1
EchoAlpha
Planned Sidetrack Well
Sample - AlphaAll depths referenced to Sample Alpha DFE 150.0ft
West(-)/East(+) [ft]
South(-)/North(+) [ft]
0
0
200
200
400
400
600
600
800
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1000
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1400
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-1000 -1000
-800 -800
-600 -600
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-200 -200
0 0
200 200
400 400
600 600
800 800
1000 1000
1200 1200
1400 1400
1600 1600
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60006500 7000
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4000450050005500
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40004500500055006000
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40004500500055006000
6500
7000
45005000550060004000
4500
5000
5500
Planned Sidetrack Well
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To set up a Ladder Plot:
1. Set the Anti-collision scan limit and the Depth range, both of which
are defined in the AntiCollision Setup dialog. The scan limit sets the
maximum value on the Y separation axis.
2. Select the designs for inclusion in Offset Designs.
3. Start the Ladder Plot.
Optionally
• To change the scaling area of the graph click Graphics Options.
• Select the scan method defined in Company Properties (usually
defined by Company Policy).
The following is a list of the graph toolbar icons for the ladder view
that are commonly used to help assess any collision risk:
Click... To...
Display uncertainty ellipse magnitudes (R1 + R2) relative
to each wellpath.
Color wellpaths with appropriate ratio factor warnings.
Display Equivalent Magnetic Distance of casing in offset
wells.
Use mouse to read wellpath name,
center-to-center separation, etc.
Access Graphics Options dialog to change Y-axis scale.
Note: Helpful Hints
• Always plot error bars to assess collision risk. Horizontal wells can have a
very large lateral uncertainty.
• Use the Line Data Reader to determine the exact closest point.
• Try limiting your Scan Limits in the Interpolation Interval dialog to more
accurately assess critical areas.
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The following Ladder Plot displays calculated separation of all offset
wells located in the Alpha and Echo Sites. The Echo wells are those that
come in from the top-left of the plot:
The above plot displays the center-to-center separation relative to the
planned sidetrack wellpath (A1-S2P1). The plan itself is not visible; it is
plotted along the X-axis. From this graph we can see that three offset
wells require investigation:
� the wellpath that departs from the X-axis at 4600 ft
� the wellpath that approached at 6300 ft
� the wellpath that approaches at 7600 ft
All other wellpaths scanned against can be discounted as anti-collision
risks using this graph, as they don’t approach the sidetrack, and if you
include error surface magnitudes, there is no overlap of the error
surfaces against the X-axis. The wellpaths that interfere are A1-S0, the
parent wellpath, A2-S0, and E4-S0 as seen in the Spider View on the
A1-S2 plan. A1-S0 at 4600 ft displays where the sidetrack launches
from the parent, so it poses no anti-collision risk.
The graph above has error bars turned on for each wellpath. These error
bars plot the sum of the uncertainty ellipses of both the plan and each
offset well (R1 + R2), assuming the error surface selected in Company
Properties (Elliptical Conic/Circular Conic). The reason why the
planned sidetrack wellpath has no error bars plotted along the X-axis is
because its own error surface magnitude (R1) changes for each offset
Plan: A1-S2P1 (A1/A1-S2)
Measured Depth [ft]
Centre to Centre Separation [ft]
4400 4600 4800 5000 5200 5400 5600 5800 6000 6200 6400 6600 6800 7000 7200 7400 7600 7800 8000
0
1000
2000
3000
4000
5000
6000
7000
8000
A2-S0E4-S0
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well. So, R1 error magnitudes are included in the error bars plotted
against each offset wellpath.
In this example, the Ladder and Spider Views enable an engineer to
determine that the only wellpaths that pose any form of anti-collision
risk are A2-S0 and E4-S0. You can use the Anti-Collision Offset Wells
tool to turn off all other wellpaths in the anti-collision scan.
The following graphic depicts a Ladder View displaying A2-S0 and E-
S0 collision risk:
The above ladder graph displays the collision risk determined for A2-S0
and E4-S0 wellpaths. The other wellpaths in the Alpha and Echo sites
are turned off using the Offset Designs tool.
Highlights are added that display the line data reader results for the
closest points. The wellpaths themselves are shaded blue, green, and red
to display warning factors. Both wellpaths have reasonable separation
(152.68 and 155.81 ft) at the calculated closest point; however, with the
error bars turned on, you can see that the planned sidetrack well error
surface overlaps on both wellpaths. This occurs where the error bars
intersect the X-axis.
Over this area, the calculated separation factor is less than 1.00, which
means that within the accuracy of the survey tools, you cannot tell if the
Plan: A1-S2P1 (A1/A1-S2)
Measured Depth [ft]
Centre to Centre Separation [ft]
5400 5600 5800 6000 6200 6400 6600 6800 7000 7200 7400 7600 7800
0
100
200
300
400
500
600
700
800
900
A2-S0: X: 6200.00 MD: 5964.02 INC: 49.23 AZ: 79.02
Y: 152.68 TVD: 5290.24 N/S: 510.63 E/W: 1942.96
E4-S0: X: 7625.00 MD: 7717.06 INC: 49.76 AZ: 268.10
Y: 155.81 TVD: 5766.78 N/S: 533.97 E/W: 3270.81
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wellpaths are going to collide or not. This is an unsafe situation. The
only solution here would be to redesign the planned sidetrack trajectory.
Equivalent Magnetic Distance
The Equivalent Magnetic Distance is a broad red line drawn on the
ladder view to show the combined magnetic effect of multiple casing
strings on the current plan. This line may be selected from the options
tab in the Graph Options, or from the Tool Bar icon.
The Equivalent Magnetic Distance line shows where the well plan
passes close to existing wells, and hence where magnetic interference
from casing can be expected. It is useful in survey program design, when
determining where to plan the switch from gyroscopic to magnetic
single shots. A simple rule of thumb is if the magnetic equivalent
distance is less than 50ft, then gyro survey tools should be used.
The scan differentiates drilled wells from planned wells by the status of
the survey program; only those wells with real surveys are assumed
drilled. Note that a program which consists of a planned section tied to
real surveys will have status planned, and will not be included in the
scan, even over the depth interval covered by the real surveys.
Additionally only the part of the wellpath deeper than the sidetrack
depth is included in the scan.
The perpendicular distance to all neighboring drilled wells is calculated
at intervals down the planned well. The combined magnetic effect of all
casing strings is then expressed as an Equivalent Distance to a single
casing string (using the inverse-square law for magnetic fields). For
example, if there are four casing strings at 18, 22, 25 and 27 meters
distance, their combined magnetic interference would be equivalent to a
single string at a little over 11 meters distance. The algorithm does not
consider casing diameters.
Separation Factor View
The Separation Factor View plots measured depth of the referenced
wellpath against the Separation Factor with the offset wellpaths. The
plot automatically plots the warning levels as defined within Company
Setup. This enables a quick review of the separation factor against
warning levels defined as company policy.
It can also be a very effective first place to look to determine the anti-
collision risk associated with an offset well. The only drawback, when
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compared to the Ladder View, is that you cannot determine the center-
to-center separation.
The example below shows the same conclusions that were determined
using the Ladder View. Both wellpaths are unsafe, with ratio factors
dipping below the lowest safe level ‘STOP DRILLING NOW’.
Reduced Error Bars with Depth
With the elliptical conic method, it is possible to observe declining
combined error surface magnitudes with depth seen most prominently
on the ladder and ratio factor views. This can be observed in the above
ladder graph for A2-S0 from 6400 ft to 6850 ft, where R1 + R2 can be
seen to reduce, and on the ratio factor view where it increased over the
same depth range before reducing again from 6900ft.
Note: Helpful Hints
• Use Graphics Options to change the vertical axis scale using Fixed Range to
something reasonable if using Scan Radius to limit results.
Separation
Plan: A1-S2P1 (A1/A1-S2)
Measured Depth [ft]
Ratio Factor
5400 5600 5800 6000 6200 6400 6600 6800 7000 7200 7400 7600 7800
0.0
1.0
2.0
3.0
4.0
5.0
STOP DRILLING NOW
Shut-in producers
Advise and Monitor
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This phenomena is not an error, and is due to the relative orientation of
the reference wellpath (our plan in this example) and/or offset wellpath
ellipsoids with increased depth. The reduced error bars occur when the
center-to-center plane changes orientation, about one or both of the
ellipsoids from intersecting from a large axis to a relatively smaller axis.
The following diagram depicts this situation:
Traveling Cylinder View
One of the traditional anti-collision plot types, the Traveling Cylinder
plot shows the polar positions of offset wells relative to the reference
wellpath center. This is the distance to the offset well at an angle that is
either measured from wellbore high side (toolface) of the reference
wellpath, or North (azimuth only when using Horizontal plane scan
method). The largest radius of the plot is the scan limit, and the distance
scale is displayed to the left of the graph. The interpolated labels on the
Reference
Wellpath
Measured Depth
R1 + R
2
Offset
Wellpath
A
B
C
D
E
F
G
H
I
KJ
Centre-C
entre Pl
ane
AB
CD E
F
G
HI
J K
Error Surface Intersection
TD
TD
Centre-Centre Plane intersects
(R2) through major axis then
around to minor axis of ellipse.
R2
R1
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traces are the measured depth of the points on the reference wellpath, not
the offset wellpath.
To set up a Traveling Cylinder Plot
1. Define the interpolation frequency and range limit in AntiCollision
Settings.
2. Select the wellpaths for inclusion in Offset Designs.
Optionally
3. Select the scan method defined in Company Setup (usually
company policy).
To determine the distance between the reference wellpath and an offset
wellpath at a given depth, follow the trace of the offset well until you
find the MD you require. Measure the distance from the center of the
plot to this point. That is the distance between the reference wellpath and
the offset wellpath at that MD on the reference well. The line data reader
is useful for determining separation.
If the offset well point is along the 180 degree line the offset wellpath is
below your reference wellpath and if along the 0 degree line the offset
wellpath is above your reference wellpath. Any other direction and the
offset well is off to the left or right as you look down the well. The 90-
270 degree line separates offset well positions that are above the
reference wellpath or below, assuming a wellbore reference.
Note: Helpful Hints
• The reference wellpath is never shown on the traveling cylinder view; it is
assumed to plot in the center of the graph.
• The center-to-center separation shown on the traveling cylinder graph is
applicable for the configured scan method. Therefore, the traveling cylinder
graph is available for all scanning methods, not just the traveling cylinder
scan method. Do not confuse the traveling cylinder graph with the traveling
cylinder scan.
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Here’s a list of the toolbar icons that are commonly used to assess
collision risk for the traveling cylinder view:
Click... To...
Toggle error ‘pedal’ surface on/off
Toggle error shadows on/off
Color wellpaths with appropriate ratio factor warnings.
Display MD labels along Wellpath. Depths are for the
reference wellpath.
Display offset Well labels at end of Wellpath.
Interactively traveling cylinder view or depth slice, used
to manually scan down the reference wellpath.
Use the mouse to read wellpath name, center-center
separation, etc.
Access Graphics Options dialog to customize plot.
Note: Helpful Hints
• Turning on Well and depth labels while in interactive mode enables you to
maintain a reference.
• Color shading provides a quick way to see where the critical intervals are
along each offset wellpath.
• If you don't see depth labels on the plot, you can set a labelling exclusion zone
(see Graphics Options).
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The following graphic depicts a Traveling Cylinder View with
Offset wellpath and error surface plotted:
The above graph refers to the A2-S0 wellpath of our example only,
E4-S0 has been turned off for clarity. The graph shows that the A2-S0
wellpath initially appears within our scan limit (10000 ft scan radius)
above and to the right of our reference well as it would appear as
looking down the reference well.
With increased depth, A2-S0 approaches to its closest point, whereby
the error surfaces are overlapping (ratio factor = 0.67). A2-S0 then
moves below our wellpath and moves from right to left.
The graph clearly displays the overlap of the combined (offset +
reference) pedal error surface with the origin of the plot. This indicates
an unsafe drilling condition; again, the sidetrack planned trajectory will
need to be re-designed and/or different survey programs planned or
conducted on the wellpaths to reduce the size of the error surface.
Pedal Curve Error Surface
The traveling cylinder plot provides a tool bar icon that enables a
statistically correct form of the combined error surface to be plotted
against the offset wellpaths. This error surface is known as a pedal
curve, also referred to as ‘footprint’, dumb-bell, or a peanut shape. This
Reference Toolface Angle [deg] vs Centre to Centre Separation [ft]
0
200
200
200
200
400
400
400
400
600
600
600
600
748
748
748
7480
30
60
90
120
150
180
210
240
270
300
330
Colour To Depth5000550060006500700075008000
43004400
4500460047004800490050005100520053005400
550056005700
5800
5900
600061006200
6300
6400
6500
6600
67006800690070007100
72007300
74007500
76007700
78007900
Wellpath A2-S0 is above and to
the right.
This depth range here displays
overlap of the offset and
reference well ‘pedal’ curves.
Wellpath A2-S0 is now below
moving from right to left.
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shape is different than all other graphics within COMPASS where an
ellipse(oid) or sphere(oid) is depicted.
The elliptical error surface is usually used to represent the positional
uncertainty of a point on a wellpath. This uncertainty can be described
mathematically using a 3D covariance matrix which describes the
mathematical derivation of the dimensions and orientation of the
ellipsoid:
where sigma n, e, and v refer to the uncertainty in an ‘earth centered’
frame of reference (north, east & vertical)
The radius of the error ellipse in any direction does not represent the
positional uncertainty in that direction. Restricting the formulae to
horizontal uncertainty, the expression to calculate positional uncertainty
for any azimuth A is:
The resultant shape of this surface is a pedal curve. This shape can be
drawn from the standard error ellipsoid by drawing tangent lines in all
directions from the ellipsoid origin, and then drawing a set of
perpendicular opposing lines connecting the first point of contact of the
line onto the ellipse.
The following graphic displays how a pedal curve can be constructed
from the systematic error ellipse:
3DCovarianceMatrix Cnev
( )=
σn2σne
σnv
σne
σe2σev
σnv
σev
σv2
=
σA Acos Asin
σn2σne
σne
σe2
Acos
Asinσn2
A2
cos σne
2Asin⋅ σe2
Asin⋅+ +⋅= =
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The pedal curve is essentially the combined ellipse distance (extremity
to extremity) + in all directions. The traveling cylinder plot assumes that
you are not on the plan, and that you can approach the offset wells in any
direction. So the combined ellipse distance computed in old COMPASS
is only in one direction; with Pedal curves the no-go zones are
determined for all directions (i.e., 0-360) about the reference and drawn
on the offset. It’s a better representation of where you can go. Note that
other limits are combined in the no-go zones, such as casing diameters
and arbitrary limits like 10m, where configured. If you use risk-based
rules, then you are no longer comparing ellipses, and the pedal curve
routine can draw weird shapes like butterflies.
Interactive Traveling Cylinder View
The Depth Slice tool bar icon activates the interactive traveling
cylinder view. The view switches to show offset data for a single depth
on the reference wellpath. The same functionality is available within the
3D Proximity view.
Using the scroll bar at the right hand side of the plot, you can change the
measured depth to any point along the reference wellpath. Like the 3D
view, you can also use the keyboard control and Up, Down, Page Down,
Page Up, Home, and End buttons to move along the reference wellpath.
For each measured depth, COMPASS plots the range and orientation
from high-side to the offset wells. In the bottom window, the wellpath
center-to-center distance and separation factor are displayed for each
offset wellpath. At any depth, if the ratio factor falls below one of the
company warning levels, that warning also appears.
Standard Error Ellipse
Pedal Error Surface
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The circle/ellipse around the offset well and reference wells represent
the error ellipse’s geometry at the current scan depth.
The following graphic depicts a Traveling Cylinder Depth Slice with
Projected Ellipse Extents:
The above example displays the interactive view with the depth set to
6850 ft on the reference well. The position of the calculated closest point
on A2-S0 is shown with its uncertainty ellipse at the depth.
The uncertainty ellipse of the reference well at 6850 ft is also shown
projected about the origin. Note that even though the ratio factor is less
than 1 (0.67), the ellipses do not appear to overlap. This is because the
ellipses are displayed using the wellpath frame of reference. If you plot
the center-to-center plane and then project those ellipses onto the center-
to-center plane, you can see (above) that the ellipses do overlap.
Offset Well Ellipse
A2-S0 @ 6850 ft
S.F. = 0.67
Centre-Centre Plane
Centre-Centre Plane
Reference Well Ellipse
Centre-Centre Plane
Reference Well Offset Well
Ellipse Projected Extent
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3D Proximity View
The 3D Proximity View provides both a 3-dimensional graphic
representation of selected well paths and a tabulated list of anti-collision
results. The graph is essentially a 3D live graph with additional tools
useful for anti-collision assessment. For visual assessment, this graph is
very useful to quickly obtain a picture of what is happening relative to
the reference wellpath. For absolute anti-collision assessment, the
Ladder View and the Anti-Collision Report provide a quicker method
for determining risk.
To set up a 3D Proximity graph:
1. Set the interpolation depths and scan limit in the AntiCollision
Settings dialog box.
2. Select Offset Designs to be shown in the view.
3. Start the Graph by selecting it from the menu.
Here’s a list of the toolbar icons that are commonly used to assess
collision risk for the 3D Proximity view:
Interactive Scroll Bar
3D Proximity computes the distance between the reference wellpath
and selected offset wells for a given depth on the reference wellpath.
Use the vertical scroll bar at the side of the graphic to change the
reference wellpath depth. As you do so, the closest point on nearby
wells, marked with a cross, changes. The positions of these markers
can change for different scan methods.
Click... To...
Project a shadow of the wellpaths on to the horizontal and both
vertical planes.
Replace the north and east walls with a vertical grid.
Display the depth plane at the current depth.
Display an ellipse down each wellpath indicating the positional
error at each point.
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The wellbore center-to-center distance and separation factor are
tabulated for each offset well. The maximum separation reported is set
in the AntiCollision Settings dialog box under anti-collision scan limit.
If no values are reported for a particular wellpath, this means that the
calculated results fall outside your scan limits.
Note: Helpful Hints
• Click and drag the left mouse button to rotate and tilt the 3D frame.
• Click and drag (up/down) the right mouse button to zoom in and out.
• Use the keyboard buttons to rotate, zoom, or step the wellpath point.
• To differentiate between wells, click on each wellpath name in the legend
box. The wellpath is highlighted on the graphic.
• To adjust the radius of the depth plane, use Anticollision Settings dialog and
change scan radius.
• Try not to rotate, zoom in and out too often, or too quickly. It is very easy to
become disoriented.
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The following graphic depicts a 3-D Proximity View:
The above example portrays a planned sidetrack well (A1-S2) together
with the parent wellpath (A1-S0) and the offset wells A2-S0 and E4-S0.
Note that E4-S0 has been drilled from another site and so comes in from
the right. From this graph you can see that the planned sidetrack well
appears to have a close approach to both offset wellpaths. It also shows
that the E4-S0 error ellipsoid is much larger than the A2-S0 error
ellipsoid. Perhaps this anti-collision problem could be solved by
surveying E4-So with a more accurate survey tool? This confirms the
other diagnosis made using the other anti-collision graphics.
A1-S0 Parent
Wellpath
E4-S0 Offset Well
A1-S2 Planned
Sidetrack
E4-S0 Ellipsoid
A1-S2 Ellipsoid
A2-S0 Offset Well
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Reports
Access the Report dialog by:
� Click the toolbar button.
� Use Anticollision > Reports
Ellipse Separation Report
The anti-collision report is a very quick and quantitative way to evaluate
collision risk for a number of offset wells. To generate this report,
COMPASS runs down the current well at intervals and calculates the
distance to each offset wellbore. The report consists of Page Header,
Report Header, Summary, and a Results section for each offset
wellbore.
Check the Anti-collision box to list the
anticollision reports. Uncheck all other boxes
to remove other types of reports from the list.
Reference Level displays
information that indicates what
reports are available.
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To set up a data scan report:
1. Select Offset Designs for the scan.
2. Define the interpolation interval, range and scan limit in the
Anticollision Settings Dialog.
3. Start the Report; from the anti-collision menu select Anti-Collision
Reports, then from the list select Anti-Collision Report.
Definition of sections:
Page Header
Printed at the top of each page the page header contains the name of
the reference wellpath, date and time, and page number. Using
Report Setup under the Utilities menu, it can also be set up to display
Company and User logos.
Report Header
The report header shows the parameters setup in interpolation
interval and the error model and warning method that are defined in
Company Setup.
Summary
The summary section shows the point of minimum separation factor
between the reference and offset wellpaths. Because separation
factor considers the size of the wellpath error ellipsoid, the point of
minimum separation factor cannot coincide with the closest center-
to-center distance.
Results
The results section contains 11 columns:
Column... Description...
Reference MD and TVD Columns 1 and 2 show the measured depth and
true vertical depth of the point on the reference
wellpath. These depths are referenced to the
drilling datum on the reference wellpath.
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Offset MD and TVD Columns 3 and 4 show the depth of the nearest
point on the offset wellpath from the point on
the reference. Note: The measured depth and
vertical depth on the offset wellpath are
referenced to the drilling datum of the offset
wellpath. The result depends on the Scan
Method selected.
Major Semi-Axis Error Ref.
and Offset
Columns 5 and 6 are the ellipse of uncertainty
major semi-axis dimensions of the reference
and offset wellpaths. When you scan with 3D
Closest Approach or Traveling Cylinder
separation, the error quoted is the maximum
"radius" of the error ellipsoid in a plane
perpendicular to the wellpath at that point.
When scanned by Horizontal Plane, the error is
the radius of the ellipsoid in a horizontal plane.
The size of the error depends upon surface
errors and survey tools assigned the current
and any parent wellpaths.
Orientation: AZI, TFO (HS)
or TFO+AZI
Orientation to set the reference wellpath to
move towards the nearest point on the offset
wellpath. The angle displayed will depend on
the anti-collision method chosen for this
Company.
Closest Approach – TFO (HS) High-side
toolface angle.
Horizontal Plane – AZI – Azimuth angle from
reference point to offset well at the same
vertical depth.
Traveling Cylinder – TFO (HS) Highside
toolface in traveling cylinders plane.
Highside + Azimuth – TFO+AZI Toolface +
the current well azimuth.
*North and East North and East are the co-ordinates of the
offset well at the depth of interest as they
would appear in a Spider Plot. The co-
ordinates have been adjusted to the origin for
the reference well (Site or Slot).
Ctr to Ctr Distance Distance from the center of the reference
wellpath to the offset wellpath in the plane
defined by the anti-collision method.
*Edge To Edge Distance This is the distance from the edge of the error
ellipsoid around the reference wellpath to the
edge of the error ellipsoid around the offset
wellpath.
Column... Description...
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*The columns marked with an asterisk do not appear on ‘rules based’
reports and are substituted with the following:
Error Ellipse Report
The error ellipse report describes the geometry and orientation of the
uncertainty ellipse with depth along the reference design. The report is
a very useful way to assess how the ellipse geometry develops along the
design. The error ellipse is computed from parameters contained in the
survey tools assigned to the active design in the survey program editor.
*Separation Factor The separation factor at that point. See
warning method for a description of separation
factor. This column does not appear in ‘rules
based’ anti-collision.
Warning In company set-up you may enter text to be
printed on anticollision reports when a
separation factor threshold is passed. In ‘rules
based’ anti-collision, the warning ‘Passed’ or
‘Failed’ appears for the appropriate rule for
this wellpath.
Column... Description...
No Go Area The No-Go Area appears on ‘rules based’ anti-
collision reports. It is the combined distance
from the offset wellpath that must not be
exceeded. It is the sum of the combined errors
(in the vector between the two wells), the
casing and hole radii and the tolerance radius
defined in the rule.
Casing Is the casing diameter on the offset well.
Allowable Deviation (from
plan)
This is the maximum distance that can be
drilled from the plan in the direction of the
offset wellpath. It is essentially the Ctr-Ctr
distance minus the No Go Area. In designing
the well plan, the allowable deviation value
should not be less than or equal to zero, or
there will be no room to drill the well.
Column... Description...
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To set up an ellipse survey report:
1. To generate an error ellipsoid around a wellpath, you must assign
tool codes to the design. To assign tool codes to an actual design, use
the Actual Design Properties dialog; to assign tool codes to a plan,
use the Plan Design Properties dialog.
2. State the interpolation interval, and range for the ellipse data in the
Anticollision Settings Dialog.
3. Start the Report, launch reports from the anti-collision menu and
then select Ellipse Survey Report from the available list.
Definition of Columns:
NOTE: Ellipse dimensions
All ellipse dimensions reported are half-axes or radii, and not diameters.
This column... Means this...
MD Measured depth
Incl Inclination
Azim Azimuth
TVD True vertical depth
Uncertainty The radius of the error envelope and its
confidence level is stated in standard
deviations from the mean, as noted in the
header of the report.
Bias The amount the ellipse center is displaced from
the center of the wellpath. Bias is caused by
error sources that have an unbalanced
distribution. For instance, magnetic surveys
often plot to the north of gyro surveys, due to
the earth’s magnetic field polarizing the
drillstring in a consistent direction.
High Side Uncertainty (cross
borehole plane)
Semi-axis error in position on the high side of
the hole (toolface 0/180).
High Side Bias Error in position lateral to wellbore.
Lateral Uncertainty Semi-axis value of error lateral to wellpath in
horizontal plane (toolface 90/270)
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Lateral Bias Lateral Bias component for the ellipse relative
to the direction of the wellpath
Vertical Uncertainty Semi-axis value in the vertical direction from
the wellbore depth.
Vertical Bias Vertical Bias Component
Magnitude of Bias This is the total displacement of the ellipse
from the center of the borehole.
Semi Major Uncertainty This is the largest dimension of the ellipse.
Semi Minor Uncertainty Minor axis dimension
Semi Minor Azimuth The direction of the horizontal minor axis from
local north.
Tool Survey tool used to measure this survey
station.
This column... Means this...
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The following graphic portrays parameters described within the Error
Ellipse Report:
Survey Bias
Survey Bias is the tendency for the most likely position of a wellpath, as
determined by the error model, to be different than its position as
calculated from survey data. This is demonstrated when the error model
calculates an error surface which is not centered about the wellpath
trajectory. For example, magnetic surveys tools can have azimuthal bias
due to a systematic effect of drillstring magnetization. Gyrocompass
error can occur due to gimballing effects.
The following graphic demonstrates this concept. The wellpath to the
left displays Wolff & de Wardt error ellipses which are centered on the
trajectory calculated from the displayed survey stations. The wellpath to
the right displays ISCWSA error ellipses, which are offset to the
calculated trajectory. A dotted line displays the ‘most likely trajectory’
which passes through the center of the ellipses, the solid line displays the
calculated trajectory. ‘Most likely’ is used as a description because the
Vertical Section View
in Borehole Azimuth
Plan View
TVD
East
V.SectionTVD
North
Vertical Unc.
Lateral Unc.
High
Side Bias
Semi-Minor Unc
Semi-Min.Azi
High Side Unc.
Lateral Unc.
High
Side Unc.X Borehole Plane =
Perpendicular to wellpath
vector at depth of interest
3 Dimensional View
Compass Error Ellipse Report
X Borehole
X BoreholeBias
Vertical Bias
Lateral Bias
Semi-Major
Unc.
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error model is indicating that statistically the wellpath position would be
at the center of the error surface.
In COMPASS, Survey Bias is shown on all ellipse drawings; it’s just
that the ISCWSA model is the only error model in COMPASS that
generates bias errors, so it is not observed on Systematic Ellipse error
surfaces.
Systematic Ellipse Error Surface
ISCWSA Error Surface Displaying ‘Bias’
Calculated Trajectory
‘Most Likely’ Trajectory
Survey Bias
Survey Station
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Chapter
Survey Module
Overview
The Survey module calculates drilled wellbore trajectories from entered
survey data using the company-specified survey calculation method,
such as Minimum Curvature. The module can be used to enter
traditional survey data (MD, Inc. & Azi), Inertial Survey data (TVD, N,
E), and Inclination Only survey data (MD, Inc.). Using an assigned
survey tool error model for each survey, the wellpath positional
uncertainty over the depth range of the survey can be calculated and
included in the actual wellpath, to be used in anti-collision calculations.
The main components of the Survey module are:
� Survey Properties
� Survey Import
� Survey Editor
� Project Ahead and Interpolate
� Quality Assessment tools
� Survey Analysis
� Survey Reports
� Survey Export
Properties is used to enter the survey tie-on point, and assign a survey
tool. The Editor lets you type in survey measurements, compute the
wellpath trajectory, project ahead from any point to a target location,
depth on a plan, or calculate a trend using existing survey data to a MD
or TVD. You can also interpolate points on the survey by either MD,
TVD, Inc., or Azi. Quality control tools enable a user to check for the
presence of errors in the data that can be immediately corrected.
Analysis tools enable you to create comparative T-Plot charts as well as
assess survey data quality using graphs or reports. Survey Reports let
you preview canned reports supplied with COMPASS. Export tools
enable survey data and almost all other data available within COMPASS
to be exported in a variety of user defined formats to a text file or the
Windows clipboard.
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Defining New Survey Properties
Before creating a new survey check the Status Box to ensure you are
entering the survey into the correct Company, Project, Site, Well, and
Wellbores.
To create a new survey, use one of the following two methods:
� From the menu bar select Survey > New Survey
� Right-click in the browser on the Wellbore or Design name and
select Insert Survey.
Naming and Specifying General Information About the Survey
The most important items in Survey Properties are the name, survey tool
and the tie-on point designation. An intuitive survey naming convention
should always be adopted and supported within a company so that
unfamiliar survey data can be easily recognized. Two good
recommendations are to include the hole size the survey tool was run in,
as well as the tool name itself. Examples of easily recognizable survey
names are:
� 12-1/4” Sperry-Sun MWD
� 9-5/8” Finder Gyro (0hr)
� 13-3/8” Keeper Gyro in Csg
� 26” Totco
You can also enter Description, Company, and Engineer details to
provide additional information about the survey, although this is not a
system requirement. Company and Engineer fields are populated
automatically with your name and Company name when a new survey
is created.
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The following graphic depicts the Survey > Survey Properties >
General tab.
Note: Survey tool determines error radius during anticollision.
The survey tool you assign determines the error radius around the wellbore during
anticollision. If you do not specifically assign a toolcode, COMPASS will assign
the default survey toolcode to this survey.
Ensure that the survey is
given an intuitive name to
help other engineers
reference it.
To prevent
unauthorized
changes to the
Survey, lock it!
Inertial - Imported
surveys that do not get
re-calculated.
Inclination only
surveys (e.g.
TOTCO)- Surveys with
no azimuth column.
Specify the dates that the
survey began and ended.
Select the Survey
Tool from the drop-
down list. If the desired
tool is not listed, use
File > Properties >
Company > Survey
Tools to define the
tool you want to use.
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Specifying the Tie-On Point
You can choose between three tie-on point methods. The tie-on point
can be defined explicitly, tied to the wellhead location, or calculated
based on a specified measured depth.
You may select a different survey to tie-on to from the drop-down list.
The start point (tie-line) items are as follows:
The three tie-on point methods are discussed below.
Note: Sidetracks...
If starting a sidetrack, you should create a new wellpath first.
This start point... Does this...
MD Starting measured depth for the survey.
Inc. Starting inclination from vertical. Vertical is
zero degrees.
Azi Starting direction from Local North.
TVD True vertical depth measured from the active
Datum.
N/S North distance from the local coordinate
center.
E/W East distance from the local coordinate center.
Tie the survey to the
wellhead, a user
defined point in space,
or to any depth along
another survey.
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Specifying User Defined Tie-On Points
Type in the coordinates and depth of the start point. This is attaching the
survey to a free point in space. No checks are made to ensure the validity
of this tie-on point. It is assumed that you know why you are using this
method.
Specifying Tie-On Points From Wellhead
COMPASS will start the survey at the N/S E/W co-ordinates of the well
or the well reference point. You may still specify inclination and
azimuth should the start point be non-vertical.
Specifying Tie-On Points From Survey
Ties on to the last point on the selected survey by default. You can
specify another measured depth to interpolate from within the survey.
User Defined - you may define all the
values of the tie-on point. Nothing is
calculated for this point.
From Survey - enter a MD from
within the Survey and
COMPASS will interpolate the
other values.
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Validating Survey Data
Use the Validation tab to specify survey validation parameters. Refer to
“Input Validation” on page 281 for more information.
This is the average dogleg severity
over entire survey. This value may be
equated to tortuosity and is a
measure of the average roughness or
noise in the survey measurements.
When Input Validation is
checked, COMPASS examines
each survey to determine if that
survey observation results in a
dogleg greater than the Dogleg
Tolerance. The excessive
doglegs are displayed in red on
the Survey Editor.
Specify the maximum dogleg tolerance to
be used during input validation.
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Managing Survey Data
The Survey Editor is essentially an enhanced spreadsheet with built-in
survey calculation functionality. The spreadsheet enables surveys to be
easily edited and viewed, and forms an area where additional tools can
be launched. If a survey editor is open, any live views highlight the
depth range of any survey data entered.
Some general rules apply to the Survey Editor:
� The first row, row 1, is the tie-in point that is defined in Survey
Properties and may not be changed in the survey editor.
� The current MD (Measured Depth) must be greater than the
preceding MD.
� Inc (Inclination) must be in the range 0-180 degrees.
� Azi (Azimuth) must be in the range 0-360 degrees.
Using the Survey Editor
The Survey Editor is the data entry grid for manually adding or editing
survey stations. Once you have entered or imported the survey, it is a
good practice to save it right away and then complete a Varying
Curvature scan to check for poor-quality surveys.
To access the Survey Editor, double-click on the survey name in the
Data Viewer portion of the Status Window. The Survey Editor is
automatically displayed when you create a new survey.
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Interpolate the current
survey by MD, TVD,
Inc or Azi.
Use Project Ahead to project ahead to:
• see existing directional trend
• determine directional parameters to hit target
• perform back-on track calculations to plan
• perform look-ahead anti-collision
If you press Enter
without typing in a new
MD, COMPASS will
automatically increment
the MD. If you are
incrementing from the
first line the amount will
be 100 feet unless depth
units are meters in which
case it is 30m. If you are
incrementing from
subsequent lines, the
additional MD is
computed from the
previous two lines.
To delete a row, click on the
row number in the grid and
press the keyboard Delete
button. To insert a row,
highlight row above which you
want to insert and press the
keyboard Insert button.
When entering or editing inclination
only surveys the azimuth column is
not available. It is assumed zero and
the North and East co-ordinates are
computed to be vertical below the
start point.
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Using the Survey Editor Tool Bar
The Survey Editor has a tool bar with the following functions:
� Save - Save the survey.
� Save As - Save the survey using a different name.
� Undo - Undo the last change.
� Redo - Reapply the last change.
� Survey Properties - Access the Survey Properties dialog. See
“New Survey (New Wellbore)” on page 117 for more information.
� Import - Import survey data. See “Importing Survey Data” on
page 282 for more information.
� Interpolate - Use to interpolate surveys along the survey. See
“Interpolating Surveys” on page 271 for more information.
� Project Ahead - Determine if a path is on course to hit a target or
specific MD/TVD. See “Project Ahead” on page 273 for more
information.
� Survey Comments - Add comments or annotations to the survey.
Interpolating Surveys
Use the Point Interpolation dialog to determine the survey position and
vector for depths that do not coincide with survey station depths. You
can enter as many points as you require into the interpolation grid at a
time. If the entered depth is above the tie-on depth of the survey or plan
then the definitive survey will be interpolated. If the entered depth is
Save
As
Save
Survey Properties
Interpolate
Project
Ahead
Survey Comments
Close editor
Help
Undo and Redo
Import
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below the end of the survey then a straight line is projected to that depth
beyond the end of the survey.
Results are available by clicking on the Notepad button at the bottom of
the window. This enables the interpolated results to be printed,
incorporated into another document via the Windows clipboard, faxed,
or emailed.
The following graphic depicts the Survey Point Interpolation Window.
The Interpolation algorithm used is determined from the Calculation
method specified in Company Properties > Calc Defaults tab. This is
also true for the Definitive Wellpath Spreadsheet Interpolation tool and
the Casing, Formation, and Annotation editors.
Depending on the calculation method you might get some unexpected
results. For example, Minimum Curvature uses the 'great circle route'
between two survey stations. If the first station was at 1 deg inclination
with heading due north and the second survey station had 1 inclination
deg due south. Minimum Curvature would track the path going under
itself (around the sphere), hence the point halfway would have zero
inclination! Radius of curvature tracks the path going around the
cylinder (like a spiral), so all intermediate points would have the same
inclination, and azimuth would go 0 to 180. But Minimum Curvature
has the least overall angle change. You can prove the same thing in
planning by using Dogleg/ Toolface to the same inclination—the
Results are available in text format using the
Windows Notepad feature. This may be
printed, copied to clipboard, or sent/emailed
to a colleague.
Within the current survey can interpolate by MD, Inc, Azi or TVD.
For each method, the other entry parameters plus N/S, E/W, VSec
and DLS are calculated.
Highlight the desired row,
and click Create Target to
add interpolated survey
point as a target. The
target will be added to the
File > Properties >
Project > Targets editor.
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Chapter 7: Survey Module
interpolated inclinations will dip in the middle, whereas the Build/Turn
equivalent will maintain a constant inclination.
Project Ahead
Project Ahead is a very useful tool to determine whether a wellpath
currently being drilled is on course to hit a target or project to an MD or
TVD using a set of directional drilling parameters. If it is determined
that the wellpath is not on course, Project Ahead can be used to
determine what is required to get the wellpath back on track to a plan or
directly to a target. Directional drilling parameters for both rotary and
steerable drilling assemblies can be determined.
The projection is made from the open survey, plus the initial hold length.
Should stations be added to the survey, the projection recalculates from
the end of these. If anti-collision is currently being used, then the
projection is included in the current anti-collision scan to enable ‘look
ahead anti-collision.’
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The following graphic depicts the Project Ahead Window:
Results are available in text format using
the Windows Notepad feature. This may
be printed, copied to clipboard or
sent/emailed to a colleague.
Enter values here for
the projection,
depending on what
method is selected.
Project Ahead to An
Object:
• Target
• Formation
• Plan
Specify Initial Hold Length to apply a hold or calculate a trend for this
length before computing doglegs to hit the targets or define trend.
Whether projecting to target or a free projection, you can apply an initial
hold section to represent the already drilled wellbore behind the bit.
This is especially useful when you consider that the survey instrument
can be 50ft or so behind the bit. COMPASS enables a user to include
a hold section with 0.0 deg dogleg through this interval, or a trend can
be calculated from adjacent survey data. This section is included in the
Projection Steps grid.
... or calculate a User
Defined Projection
using:
• Dogleg/Toolface
• Build/Turn
• Trend calculated from
survey
The target aiming point
can be adjusted laterally
and vertically.
The Projection Steps
grid displays the results
(below) and the trajectory
determined for the hold
section.
Click Calculate to
calculate and observe the
Projection Steps.
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Project Ahead can operate in one of two ways:
Two other areas in the window complete the dialog. The parameter entry
area enables you to enter MD, TVD, Dogleg/Toolface, and Build/Turn
values as required by the projection method. Below lies the results grid
that displays the directional drilling parameters of one or more projected
sections.
The following graphic depicts the Projection Parameters Area:
Use the... If you want to...
Project To Target / Plan or
Formation
Specify the required location and let
COMPASS compute the trajectory changes
using one of the trajectory types. If a plan has
been selected, it shows the actions required to
take the wellpath back to the plan. This also
works for dipping formations.
User Defined Projection - Curve
Only
Specify the projection distance to an MD or
TVD and the curve rates, and then let
COMPASS compute the new location.
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Projecting To Target / Plan or Formation
The following graphic depicts the Project to Target or Plan Area within
Project Ahead:
Procedure: Using the Project To Target/Plan or Formation Option
1. Select the Object to Project to:
• Target: Select a target from the target list, or enter a point to aim
for. If you don't see the required target on the list you have not
allocated it to the wellpath list. When a target is selected, the
tabular display is updated and shows the requirements to hit five
extremity points on the target for Curve Only, or displays the
projection sections for Curve-Hold and Optimum Align.
Projecting to a target enables the use of the Landing Point adjust
feature in the Target Viewer. Click on Landing and the Target
Viewer appears, which enables you to select any point to Project
to.
Choose a Wellpath Projection Type:
• Curve Only - Single section: continuous steering to the
Target/Plan
• Curve+Hold - Two sections: steer to line up on Target
then hold to hit the target
• Optimum Align - Three sections: steer, hold, then steer
again to line up on target or align wellpath back with
the plan
• Ouija Board - Modify the current project ahead view to
allow calculation of two of the following when the
remaining two are specified: final inclination, final
azimuth, dogleg, or tool face angle.
Select a Target, Formation,
or Plan defined within the
current wellpath.
Select a Target from the list
currently associated with the
current wellpath.
If projecting to a target,
override the target’s
aiming point by selecting
a new location vertically
or laterally using the
Target Landing Adjust
feature.
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• Plan / Formation: Select the plan or the formation to steer into.
This method not only returns the wellpath back to the plan, but
also directs the well so that it aligns with the correct inclination
and azimuth.
2. Choose the Wellpath Projection Type to get to the point:
• Curve Only: Projects a single curve to the target or plan point
through continuous steering. COMPASS calculates the dogleg
required for the projection.
• Curve and Hold: Can be used for slant wells and sidetracks
where the intercept point is close to the target. Curve+Hold adds
two sections. The curve gets you aimed at the plan/formation and
then holds until it’s been hit. While this method returns you to a
point on the planned wellpath, it does not align you with the
direction and inclination of the plan.
Curve + Hold requires the dogleg severity for the curve to be
entered in the parameter fields below. If not entered, a Projection
Warning window displays, explaining that it is not
mathematically possible to project to the required point.
• Optimum Align: Method is best applied to horizontal wells,
where full steering control is possible. Optimum align adds three
sections—curve / hold / curve. This not only returns you to the
planned wellpath, but when you select the plan you are on, the
planned inclination and correct azimuth displays at that point.
This projection also requires the dogleg severity for the two
steered sections to be entered.
• Ouija Board: COMPASS modifies the current project ahead
view to allow calculation of two of the following parameters
when the user enters the other two:
•Final Inclination
•Final Azimuth
•Dogleg
•Tool face angle
3. You need to set the measured depth you want to reach in the plan,
and the dogleg severity to use in steering. If you specify a measured
depth that is too short to reach the plan, the program cycles depths
in 10' (5m) increments until the plan can be reached.
4. When all parameters are defined, click Calculate to generate the
Projection. Depending on what has been requested, one or more
rows appear in the results grid. Projections to targets can display
parameters to hit different points on the target, projection, or
projections to user selected aiming points. Curve+Hold and
Optimum Align projections display section details. All rows in the
results grid display the Build & Turn rate required for rotary
drilling assemblies, Dogleg/Toolface required for steerable
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assemblies and the projected point, including MD, TVD, Inc, Azi,
N, E, and Vsec.
The following graphic depicts the Project Ahead - Optimum Align to
Target results:
The Projection Steps results grid also displays the directional
parameters calculated for the hold section, whether hold or calculated
for trend. This information is very useful to a directional driller who
includes the information when setting up their tools for a slide.
Click Notepad button in the tool bar to make Projection details available
as a text file that can be shared with other engineers.
If the object projected to is a target and the Projection is Curve Only,
COMPASS displays a number of Projections to hit different locations
on the target:
The following graphic depicts the Project Ahead results to Target for
Curve Only:
You can interact using the Live views and the different projected
sections. Clicking on a row in the results grid results in that projection
being displayed in all live views.
Using the User Defined Projection - Curve Only
User-defined projections enable ‘what if’ type projections to be
completed to a MD or TVD through continuous steering only. For rotary
drilling assemblies, you can define Build and Turn rates; for steerable
drilling assemblies you can define a Dogleg and Toolface Orientation.
To determine if a wellpath is on course to a target or other location, a
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trend can be established from a number of existing surveys to a MD or
TVD.
The following graphic depicts the User Defined Projection in Project
Ahead:
1. Select the Depth to Project to:
• MD—Measured Depth
• TVD—Vertical Depth
Depths must be entered into the parameter entry fields below.
2. Select the Projection Type:
• Build & Turn Rate (for rotary drilling).
• Dogleg Rate and Tool Face Orientation (for steering drilling).
• Apply the Trend over a number of previous survey points (to
continue the current trend) or Hold for a given Bit-Survey tool
distance. You can enter the number of survey points to construct
the trend directly, or use the up/down arrows to change the
number of points.
3. Enter the necessary projection parameters highlighted in the line
below, then press Calculate.
The results grid populates, and any live views are updated to display
the Projected section.
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The following graphic depicts the COMPASS 3D view displaying
Project Ahead Curve+Hold from a survey ending at circular target T1
projecting ahead to rectangular target T10:
Survey Data Quality
One of the more useful tools in COMPASS enables you to check for
errors in the survey data. The large amount of survey data typical of
modern surveys means that it is very difficult to visually assess whether
any errors are present and if they are, where they are located.
Unfortunately, survey errors are very common due to a number of
reasons that include:
� Typing/communication (language) problems
� Inconsistent interpretation of survey measurements
� Bad individual survey
� Survey tool operating incorrectly
� Survey tool run badly
� Incorrect tie-on points
Because of the large source of errors and potentially serious
consequences, every survey should be checked and ideally, each
company should have some form of survey quality control procedure in
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place to ensure that these errors are detected. Remember, the surveyor
should be checking for errors too!
You can assess the quality of the survey data using Input Validation to
check for high doglegs, or use the more rigorous Varying Curvature
method, which checks for the individual effect that each survey
observation has on the calculated bottomhole location.
Both tools allow you to determine the depth of any suspect points that
can be fed back to the surveyor for them to check.
Input Validation
The Input Validation is configured using the Survey Properties >
Validation tab. When turned on, survey observation calculated dogleg
severities higher than the validation dogleg severity are highlighted in
red. Remember, there are valid reasons for high local doglegs, such as
controlled directional drilling. Refer to “Validating Survey Data” on
page 268 for more information on specify validation criteria.
The following graphic depicts Input Validation in the Survey Editor:
With Input Validation on, the entire survey should be parsed to check
for suspect doglegs. If there is any question about a survey point, get the
surveyor to check it or delete the survey.
6.11 deg/100ft dogleg
highlighted in red.
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Importing Survey Data
COMPASS enables survey data to be imported from other sources; for
example, from the survey contractor at the rigsite or directional drilling
office. The Survey Import feature is one of the best tools to reduce errors
in the survey data entered into COMPASS by eliminating the potential
for typing mistakes when survey readings are re-entered. It is designed
to be flexible and easy to use.
To import survey data, click the toolbar button.
To import survey data, you must know exactly how the survey data is
formatted in the source data location. Normally, the COMPASS user
would agree to a format with the surveyor/contractor, or the operator can
simply dictate exactly what the format should be. The following graphic
depicts the Import Survey window:
Whatever the data location or format, COMPASS survey data import
reads only the data from rows in the source location that have the correct
format. Any rows in the source location that do not have the exact
specified format are ignored. This is quite useful, as it means that other
parties can include survey header information, such as column titles and
Inclination Only
data will be
imported.
COMPASS will
calculate TVD but
not Azimuth N or E.
To complete the
import format, select
Blank/Tab as the
column separator, or
simply type it in.
Import survey data from a
Text File or the Windows
Clipboard.
Select the appropriate
units of the source data
set. COMPASS will convert
the data as it is imported to
the current unit set
configuration if necessary.
Choose the type of
survey data to import.
Define the column
order of the data table
you are going to import.
Define the numeric
delimeters used for
countries where
commas are used
as decimal
separator.
Specify corrections to the input
survey data. These values will
be added or subtracted from the
survey as it is imported. Normally, the survey
contractor would complete all corrections,
utilizing their own software prior to making the
survey data available. Note: negative values
can be entered into these fields
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units, or other notes about the survey data that is passed over during the
import process.
Survey Types
COMPASS is capable of importing different types of corrected and
partially corrected survey data. COMPASS can read in the survey
observations and is capable of applying minor corrections to the data as
it is imported.
Different types of surveys that can be imported are:
Normal Survey
A survey consisting of MD, Inclination and Azimuth. From this,
COMPASS computes the TVD, N/S and E/W of each survey station.
Use this method when importing three values, such as:
Inertial Survey
A survey consisting of 6 columns: MD, Inclination, Azimuth, TVD, N/S
and E/W. COMPASS reads the co-ordinates (TVD, N/S and E/W) of
each survey station. MD, Inclination and Azimuth are not back
calculated. Use this method when importing all six values.
Inertial Survey - Calculate MD/Inc/Azi
A survey consisting of 3 columns TVD, N/S and E/W. COMPASS reads
the co-ordinates (TVD, N/S and E/W) of each survey station and back
calculates the MD, Inclination and Azimuth, using a method consistent
with Minimum Curvature. Should the standard import result in erratic
Inclination and Azimuth, then use the Spline switch & this will compute
MD Inc Azi
100 0.1 345.1
200 0.5 300.2
MD Inc Azi TVD N/S E/W
100 0.1 345.1 100 -2.5 5.5
200 0.5 300.2 200 -2.7 5.8
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smoother angles using a 3 point spline method. Use this method when
importing three values, such as:
Inclination Only
A survey consisting of 2 columns MD and Inclination. Other columns
are ignored. Compass will import the survey calculating the data as for
an inclination reading instrument (TOTCO). The azimuth will be
assumed to be zero and N/S and E/W will be computed vertical below
the start point. Use this method when importing two values, such as:
MD N/S E/W
100 -2.5 5.5
200 -2.7 5.8
MD Inc
100 1.50
200 1.75
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Analyzing Survey Data
Using Varying Curvature
Use Survey > Data Analysis > Varying Curvature to access the
Varying Curvature Setup dialog.
Varying Curvature is used to check survey data quality. Varying
curvature considers the effect on the calculated bottom hole location of
each survey point by removing each point from the survey and
recalculating the trajectory. For each station the calculated result is
called inconsistency—this is the distance the calculated bottomhole
location would move if a survey observation were removed, and this
value is expressed as a percentage of the adjoining survey’s depth
interval. For example, if the measured depth interval of your survey
stations is 100ft, and the removal of an observation moves the bottom
hole location by 5ft, then the inconsistency value of that observation is
5%.
The following graphic depicts the Varying Curvature algorithm:
To help filter out suspect observations, a Tolerance limit can be defined,
essentially a Quality Control level. Any observation above this tolerance
is plotted in red and summarized on the varying curvature report.
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As a general rule, any observations with an inconsistency greater than
2% are suspect. However good-quality survey data with a very low
mean inconsistency can show suspect inconsistencies much lower than
2%.
Varying Curvature tools are accessed from the Data Analysis submenu
in the Survey menu of the COMPASS menubar. When accessed, a
choice window appears. You can choose to review a varying curvature
report, launch a 2D varying curvature graph, or a 3D varying curvature
graph.
The following graphic depicts the Varying Curvature Selection
Window.
Using the 2D Varying Curvature Graph
The 2D varying curvature graph plots total inconsistency against
measured depth of the survey. It is an easy graph to interpret; all one has
to do is look for irregular spikes in the data, read off the depth of the
spike using the line data reader, then check the survey observation data
at that point. These graphs are live, so you can move the survey editor
to see both editor and graph, update the observation in question, and
immediately assess whether the correction has removed the spike.
Varying Curvature Analysis Options:
• Produce a graph of combined
inconsistency for each survey station
• Produce a graph of Inconsistency split into
its vertical and horizontal components
Define Quality Level to be
highlighted in graphs or
appear in reports.
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The following graphic depicts an example of 2D Varying Curvature
Graph:
The example above displays two suspect points. Even though their
inconsistency is well below the tolerance, both of these points should be
checked with the survey contractor. It could well be that these survey
stations were reported incorrectly, or were incorrectly recorded by the
survey hand.
3D Varying Curvature graph
The 3D varying graph separates inconsistency into it’s vertical
(high/low) and horizontal (left/right) components and plots it against
measured depth of the survey. Spikes in the high/low side graph are
mainly due to errors in inclination. Spikes in the left/right are mainly due
to errors in azimuth.
Use the Line Data Reader to see
survey station details of any suspect
points within the survey
Despite being below the 2% threshold, it would be
advisable to check the survey measurements on both
these stations.
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The following graphic depicts 3D Varying Curvature Graphs:
The example above displays the two suspect points as an error in
inclination at 1496 ft. and an error in azimuth at 2923 ft. With this
information, one could phone up the survey hand to check the
inclination and azimuth at these depths and get them to report back if the
survey requires a correction.
Using Graphs to Analyze Survey Data
Analysis Graphs enable the production of comparison plots of survey
and plan data. You can for example plot MD against inclination or
azimuth or Dogleg Severity against Wellbore Inclination to see how
well the directional driller is controlling direction as he builds angle.
Multiple surveys can be overlain to compare different surveys within the
same hole section, plot planned trajectories against actual, or assess
survey variation against that defined by the survey tool error model.
A comparison of dogleg against MD can indicate areas of possible
casing wear, or indicate locations where keyseating can occur.
Similarly, dogleg against TVD can indicate which formations were
difficult to drill.
Likely Inclination
ErrorLikely Azimuth Error
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There are two options available, Min/Max graph or Analysis Graphs.
Max / Min View
You must have a survey open to gain access to Max / Min View. The
Min/Max view displays two graphs:
� Inclination against measured depth
� Azimuth against measured depth for the entire measured depth
range of the current survey
Additionally, the title area details the range of inclinations and azimuths
present in the survey data. This graph can be useful as a first quality
control check on survey data. However, varying curvature scan offers a
more rigorous method of identifying poor survey data.
Analysis Graphs
To create analysis graphs, first open the survey you wish to plot, then
choose Analysis Graphs from the Data Analysis submenu in the main
Survey menu.
The next step depends on the type of analysis you require. You have a
choice of two types of graph selection. COMPASS is supplied with a
number of commonly used Predefined formats, mainly against
Measured Depth. In addition, User Defined plot formats can be
generated.
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The following graphic depicts Pre-defined Survey Analysis Graphs:
You can choose to cross plot as many graphs as you like at a time, but
this is realistically limited to the amount of vertical resolution required.
Too many graphs, and it is difficult to interpret or even see any change
in the data in the graph.
Like all COMPASS graphs, Analysis Graphs come supplied with the
usual toolbar icons; they can be printed or sent to Print Preview to see
what would be sent to the printer.
Plotting Multiple Surveys
Additional surveys can be included in an existing graph for comparison
purposes. For example, you may want to compare survey tool results
over the same section of wellbore to see if the extra time running a Gyro
survey was well spent.
Additional Surveys may be selected using the toolbar button.
Choose
between
canned
comparisons or
user defined or
define your
own formats
Select parameters to
cross-plot from dropdown
selection lists.
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The following graphic depicts an Analysis Graph cross plot displaying
comparative survey data:
The above example is taken from the COMPASS training course. The
plot displays two surveys—an Electronic Multi-shot (EMS) survey, and
a series of conventional SRG single shots, run over the same depth
interval. The top inclination graph shows that the well profile is build,
hold and drop—an S-well. It also shows no real difference between the
two sets of survey data. On inclination at least, the two surveys agree.
The second azimuth graph shows that the well is being turned slightly to
the right through the build section, then roughly holds direction until the
end of the survey. Looking at the survey data, one can see that as the
well builds angle, the surveys start to disagree, and that it is the
Magnetic data which is displaying a higher azimuth. When the
inclination starts to drop, one can see that the magnetic data drops back
into line with the single shot gyro data. This type of behavior would
suggest that the magnetic data is subject to some form of inclination-
driven interference that is not affecting the Gyro readings—possibly the
survey tool has been poorly located and is being affected by drill string
magnetization. Alternatively one can see the sudden shift in the trend of
the gyro data at 1500ft and say that it is suspect from that depth.
Whatever the reason, the graph clearly shows that there is a difference
in the survey readings and that further investigation is required.
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Relative Instrument Performance
Expected measurement errors for Inclination and Azimuth axes may be
displayed on the analysis graphs by clicking the error bars button
on the toolbar or in graphic options. The quality of overlapping
surveys may be determined by evaluating the actual inclination and
azimuth differences against their expected performance shown by the
error bars.
The error bars on survey analysis graphs are a combination of the errors
on both the reference survey and the survey chosen for comparison
(using RSS addition of independent sources of error). Note that the size
of the error bars is determined from the confidence level chosen for
Output Errors in customer set-up.
The following graphic displays a relative instrument performance:
The above graph compares the SRG and EMS surveys. Looking at the
Delta Inclination data, there is considerable variation between the two
surveys; however, no trend can be observed between them. When
comparing against the expected variation due to error, the variation is
greater than expected for the tool error models and the confidence level
defined within the company.
Turn on error bars to see how the
survey tool performed against its
defined error model.
These graphs compare surveys, so
at least one additional survey
needs to be selected to see any
results
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The Delta Azimuth graph displays a clear trend between the two
surveys, again highlighting that one of the surveys is being affected by
some physical effect which is not affecting the other survey. Survey
errors are almost within their expected margins.
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Survey Reports
The Reports functionality within COMPASS provides a flexible, easy to
use, survey/directional well planning reporting mechanism suitable for
all users of directional drilling software. COMPASS offers several
survey reports.
Survey Reports are accessed from the main Survey menu or from the
icon in the COMPASS toolbar. Note that the reporting
functionality is available whether a survey is open or not. If the latter,
then the report details the design wellpath; otherwise, the data is for the
open survey.
The following graphic depicts the Reports dialog.
All reports can be
previewed and printed in a
professional format or they
can be output to a text file.
Click the Survey button to
view a list of survey
reports.
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Survey Export
COMPASS can export a survey, a plan, or a definitive path in any ASCII
format.
The following graphic depicts the Survey Export Window. (The same
dialog is used to export Plans.)
Export File Format
You can export using a pre-defined format or you can define your own
format. If you use a pre-defined format, you can specify some
information not to be included in the export.
Note: Exporting a Survey...
The survey editor must be open for that survey to be exported. If a survey is not
open, the open Design is exported.
The output can be directed to a file or to the
Windows Clipboard for pasting into a word
processor, spreadsheet, or the Windows
Notepad. When exporting to paste into Excel, you
should set the delimiter to tab.
Data can be exported to a file format available
from a picklist. Format files may be constructed
by clients. Refer to “Exporting to a Pre-Defined
Format” on page 296 for more information.
Check to include the final driller’s
depth (TD) at the end of the
interpolations.
Click User Defined to specify export format
details. Refer to “Exporting to a User
Defined Format” on page 296 for more
information.
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Exporting to a User Defined Format
If you want to use a User Defined format, click the User Defined radio
button. You must then specify:
1. Units: Select the units for depth, inclination, and azimuth from the
associated drop-down lists.
2. Column Delimiter: Select the button associated with the delimiter
you want to use. When exporting to paste into Excel, you should set
the delimiter to tab.
3. Interpolate: Specify interpolation details. In user defined exports
an interpolation type may be defined. When interpolations are
requested the original survey intervals are discarded in favor of
interpolated stations at regular intervals.
�Interval - The depth frequency to interpolate the survey.
�Specify depths by - Measured Depth or Vertical Depth
�Range - The start depth end depth to clip the interpolations.
�Include station at end - Attach the last recorded station at the end
of the interpolations.
�Whole Path- If a survey is open, check the Whole Path box if
you wish to include the definitive path above the tie-on point
when you export the open survey.
Exporting to a Pre-Defined Format
COMPASS allows you to configure export file formats. The format files
(*.cef) are placed in the COMPASS\CONFIG directory, and when the
export dialog is called, a drop-down list containing the different formats
available is listed.
Custom export formats can be used for a number of reasons:
� Quick export to spreadsheet of various data.
� Formats for geological or geophysical applications.
� Exports to other engineering applications.
� Preview of data in Notepad, to cut and paste.
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If requested Landmark can supply formats for a number of third-party
applications, or can assist with the development of new format
configuration files.
If you want to use a Pre-Defined format, click the Pre-Defined radio
button. You must then select the format you want to use from the drop-
down list. Items that are included in this format will become active and
be checked by default. If the item is checked, it will be included in the
export. If you don’t want to include the item, uncheck the associated
box.
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Chapter
Plots
Overview
There are two types of graphics in COMPASS.
� Live Graphs
� Wall Plots
Comparing Live Graphs and Wall Plots
Live Graphs
Live graphs or views are primarily designed for on screen viewing. This
type of graph can be output to a printer or exported to a file, however the
flexibility of Live Graphs is inferior to Wall Plots. You can use live
graphs at any time to view your work. These graphs are termed live
because they are online and are updated automatically as data is changed
in the editors or data entry windows.
You can print a Live Graph using the toolbar icon. However, a better
method is to use the Print Preview feature by clicking File > Print
Preview. The Print Preview window displays the formatted changes and
uses the actual printer driver to present the graph on the window. This
enables you to see exactly what will be printed before you send it to
hardcopy.
The Live Graphs can display different types of Wellpath data. In
addition to the Definitive Path (default color = Blue), Live Graphs
display:
• currently open Survey (default color = Red)
• currently open Plan (default colours = Red and Green)
• Survey Project Ahead sections (default color = Green)
• Other wellpaths in the Field using Offset Wells
Examples of Live Graphs are:
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• 3D view
• Vertical Section view
• Plan view
• Target Viewer
• Template Viewer
• Wellpath Optimizer view
• Anti-Collision Plots
Wall Plots
Wall Plots are designed for printer or plotter output. You can configure
a Wall Plot in many ways as you will see later in this chapter. For
presentation output, use Wall Plots in COMPASS because Live Graphs
are not WYSIWYG (What You See is What You Get). All Live Graphs
are formatted as they are sent to the printer.
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Using Live Graphs
Accessing Live Graphs
Live Graphs Common to All Modules
Access Live Graphs common to all COMPASS modules using toolbar
buttons.
� 3D View,
� Section View,
� Plan View,
� Template Viewer,
� Target Viewer,
� Optimizer Viewer,
Live Graphs in the Survey Module
Access Live Graphs in the Survey module by:
� Survey > Data Analysis > Min/Max Graph
� Survey > Data Analysis > Varying Curvature
� Survey > Data Analysis > Analysis Graphs
Live Graphs in the Anticollision Module
Access Live Graphs in the Anticollision module by:
� Anticollision > Travelling Cylinder View
� Anticollision > Ladder View
� Anticollision > Separation Factor View
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� Anticollision > 3D Proximity View
� Anticollision > Spider View - Local
� Anticollision > Spider View - Map
Customizing Live Graphs
Use the General Graph Setup dialog to configure the appearance of Live
Graphs. Access the General Graph Setup dialog by:
� Tools > Graph Setup
� Clicking the Graph Setup toolbar button.
Current Track Identification
To help distinguish different trajectories on a graph, you may assign
different colors and symbols to Definitive Survey, Current Survey, and
the Current Plan. You can’t assign a symbol to Targets.
Offset Track Identification
???How does this work now???You may assign colors only for offset
information including Offset Wellbores, Offset Surveys, and Offset
Plans.
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Multi-Color
In the options for the Offset Wellbores, Surveys and Plans you may
choose "Multi-color" which will assign a different color to each
new track. Color by Type
In the options for Offset Wellbores you may choose a pen color
based on the type defined in the Wellbore Properties. The colors are
assigned to Wellbore types in the Wellbore Type editor.
Sizes (% of the window)
Text in this category does not change size as you enlarge the view. Font
sizes are shown as a proportion of the window size, so when you change
the window size, the font sizes also change.
Sizes (% of the graph)
Text in this category changes size as you enlarge the view. Font sizes are
shown as a proportion of the graph size. When you change the window
size, the font size does not change. Also when there are multiple graphs
on a plot, such as an analysis, plot symbols and data labels are scaled to
the area occupied by each individual graph not the overall windows size.
Why is size based on % of window or % of graph?
When you enlarge graph details using zoom some text is enlarged while
other text is unchanged. The reason for this is that enlarging the titles
and axis labels gives a clear indication that the view has been magnified.
On the other hand when you zoom in to magnify detail, you don't want
to make symbols, depth labels and casing shoes, too large to read.
Symbol Spacing
The frequency (number of stations) symbols are to be plotted along a
Wellbore.
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Background
This causes the graphs to display on a black background. Black lines
will now appear as white lines.
Note: Black background color...
Setting the background color to black will not affect the printed versions of the
graphs.
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Using the Live Graph Toolbar Icons
Each Live Graph has its own set of properties and tools, but there is a
common subset of tools. The following graphic depicts the COMPASS
Live Graphs Toolbar icons:
You activate these additional tools and settings by clicking the icon. The
appearance of the graph can change, or an additional window can
appear. The most useful feature is the online help available for each type
of graph. Each graph type has its own subset of tools to manipulate the
plot, and graphic options to customize the plot.
COMPASS for Windows Live View Icon Map
Symbols
• Turn on Line Symbols for B & W Printing
• Helps differentiate lines on plot
Axis at (0,0) On/Off
• Major grid axis displayed in center or to left of plot
Formations
• Display Formation Tops
Display Error Surface
• Display ellipse of uncertainty along wellpath
• Ellipse interval may be adjusted in graphic options
• Ellipse is projected onto viewing
surface
Display Casing Shoes
• Display casing shoe symbols and labels along wellpath
Grid On/Off
• Turn grid lines on or off
• Useful to turn off grid lines on b & w plots
Display Targets
• Include Wellpath targets in plot
Vertical Section Lines
• Display Vertical Section Lines in Plan
Horizontal Section Lines
• Display Horizontal Section Lines in PlanData Labels On/Off
• Turn display of data labels on or offAxis Labels On/Off
• Turn display of axis labels on or offGraphics Options
• Access to all Live View/Wallplot Customizations
or simply double-click on graph
Point Data Reader
• Read X & Y axis values from selected point on graph
• Read Delta X & Y between 2 points on graph
Line Data Reader
• Read X & Y axis values on selected point along line
• Move Mouse to select point
Rescale Axis
• Drag mouse pointer to reduce graph area
Zoom In
• Click area to zoom in on
Zoom Out
• Click to pan out to original scale
Display Definitive Wellpath
• Turn Definitive Wellpath On/Off
Graphics Offset Wells
• Select Offset Wellpaths to include
in current plot
Print Live View
• Format, then send graphic to printer
Close
• Turn off the graph
Online Help
• Launch the Help to see the tips available for the current graph
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There are additional icons that appear on certain graphs.
Legend Box
When you launch a live graph, COMPASS also opens a Legend Box that
contains a list of all wellpaths displayed on the current view.
The Legend Box has the following features to help you distinguish
different wellpaths.
• The first wellpath is always the current Definitive Wellpath.
• If you open a survey or a plan it is next in the list.
• The next line is a blank line.
• The rest of the Legend contains additional offset wellpaths.
• Clicking on a wellpath name in the Legend Box highlights its trace
in the graphic view.
• Clicking on the blank line unhighlights all wellpaths.
• Double-clicking the name of each offset wellpath in the Legend
Box changes its color or symbol.
• To change the color of the current wellpath or survey, see Graph
Setup.
Using the 3D View
This is one of the most commonly used Live graphs, as it quickly
enables you to obtain a good overall perspective of wellpath trajectory
entered in COMPASS.
The selected wellpath line will be
highlighted in bold on all live views.
To change wellpath color or symbol,
double-click on it within the Legend
and choose from list.
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There are two types of tools available:
• Keyboard quick keys
� Toolbar icons
The following graphic depicts the keyboard quick keys and toolbar
icons:
The 3D view is actually a 2D line drawing representation of 3D. When
zoomed out, perspective is easy; however, when you zoom in and start
rotating objects, it becomes difficult to keep your frame of reference. If
this occurs, zoom out, regain your perspective, then rotate the object
back to where you think it should be, and zoom in again.
In addition to the keyboard, you can use the left mouse button to drag
the 3D view around, and the right mouse button to zoom in and out.
Using the Vertical Section View
The Vertical Section view displays the current wellpath as projected
onto a vertical plane defined in Wellpath Setup. You can add additional
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wellpaths to this plot, show target and casing details, and use the line
data reader to select points on the wellpath.
Using the Plan View
The plan view displays a horizontal projection of the wellpath. You can
display the current line of the vertical section from the origin to the end
of the wellpath.
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Using the Wall Plot Composer
What is the Wall Plot Composer?
The Wall Plot Composer is used to create and customize plot layouts for
windows, file, or professional hardcopy output by creating a template of
the page layout that can be saved and reused. A wallplot consists of any
combination of graphical and data elements generated from COMPASS,
in addition to bitmaps or windows metafiles constructed elsewhere. The
only limitation is the amount of real estate available on hardcopy.
Accessing the Wall Plot Composer
The Wall Plot Composer is accessed by clicking the toolbar button.
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Examining the Wall Plot Composer Components
What is an Object?
An object is a graph, legend, text box, or other item that is added to a
Wall Plot Composer plot. Add objects by:
• Using the Object Toolbar
• Composer > Add
• Right-click menu
Indicates the name of the plot. This plot has not
been saved, so the name is still the default
name of New Plot. The * indicates the plot has
been changed since the last save.
General toolbar
Object toolbar
Layout toolbar
Rulers indicate the
location of the printable
page area, margins, and
objects.
This section view and legend
are both objects. Objects have
sub-objects such as labels,
grids, lines, and text.
This numeric
display indicates
the position of the
cursor.
The dotted blue line
indicates the
margin. You can
change the margins
by using the ruler.
Click on the ruler
where the margin is
and move the
double-arrow cursor
to the new margin
location.
The white area is
the page. The solid
gray line indicates
the printable area
of the page.
The gray dots on the page indicate
the snap-to-grid settings that can
aid with lining up objects of the
page. Refer to “Using the Layout
Toolbar” on page 316 for
information on snap-to-grid.
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Objects can be configured, resized, and customized in many ways. The
following objects can be added:
• XY Graph
• Traveling Cylinder graph
• 3D graph
• Data Box
• Geological Column
• North Arrow
• Legend
• Text
• Pictures
• Rectangles, Polygons, Ellipses, Circles, Lines, Segmented Lines,
Curved Lines, and Arrows
What is a Sub-Object?
Objects contain sub-objects. Sub-objects can’t be moved outside of the
object they are in. Examples of sub-objects are:
• Lines
• Text
• Labels
• Grids
Setting Up the Wall Plot Composer Page
Use the Page Setup dialog to specify the paper size, margins, scaling,
and layout for printing Wall Plot Composer plots. Refer to the online
help for more specific information about dialog options.
Click the to access the Page Setup dialog.
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Using the Toolbars
The Wall Plot Composer has three toobars, including:
� General toolbar: The General toolbar is used for many functions,
including saving plots, zooming, configuring wall plot layout, and
printing.
� Object toolbar: The Object toolbar is used to select objects (plots,
data, arrow, legends, etc.) to place on the wall plot.
� Layout toolbar: The Layout toolbar is used to align the position of
objects on the wall plot and customize the grid.
Use the scaling options to
convert a plot to a larger or
smaller sized paper.
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Using the General Toolbar
Refer to the online help for more information concerning a toolbar
button than what is presented below.
Icon Description
New: Open a new template.
Open: Open an existing template file. Use the drop down
arrow to open template from recent selection list.
Save: Save the open template to file.
Save As: Save the open template with the different file name
(save as). Plots can be saved as WPC files only. Refer to
“Wall Plot Composer Files” on page 329.
Undo: Click this button to undo the most recent actions.
Redo: Click this button to redo actions that you have undone
using the Undo button.
Zoom: Use this button to zoom in and out.
Page Units: Use this button to select inches or centimeters
as the units for the Wall Plot Composer ruler.
Properties: Click this button to access the Properties dialog
to configure the selected object. If an object is not selected,
this button is not accessible.
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Using the Object Toolbar
Refer to the online help for more information concerning a toolbar
button than what is presented below.
Bring to Front / Drop to Back: Click this button to place
the selected object behind or in front of another object on the
Wall Plot. When two graphs are marked as opaque the top
component will overwrite the bottom component.
Import: Click this button to import an object from a file into
the Wall Plot.
Export: Click this button to export selected objects.
Exported objects can be imported using the Import toolbar
button.
Page Setup: Click this button to access the Page Setup
dialog. Use the Page Setup dialog to select the paper the plot
is to be designed for.
Printer: Click to send this Wall Plot to the printer.
Close: Click to close this template plot file. If the plot has
changed, you are obliged to save the layout.
Help: Click to access online help.
Icon Description
XY Graphs: Click this button and select the desired graph
from the list.
Icon Description
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Traveling Cylinder: Click this button to add the Traveling
Cylinder graph to the Wall Plot.
3D Graph: Click this button to add the 3D graph to the Wall
Plot.
Data Boxes: Click this button to select information to
include on the plot from pre-defined data groups.
Geological Column: Click this button to add the Geologic
Column to the Wall Plot.
North Arrow: click this button to add a North Arrow to the
Wall Plot.
Legend: Click this button to add a legend to the Wall Plot.
Text: Click this button to add a text box to the Wall Plot.
Picture: Click this button to add a picture to the Wall Plot.
Rectangle: Click this button to add a rectangle to the Wall
Plot.
Polygon: Click this button to add a polygon to the Wall
Plot. See Placing an Object on the Wall Plot Composer for
more info
Ellipse: Click this button to add an ellipse to the Wall Plot.
Icon Description
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Using the Layout Toolbar
Refer to the online help for more information concerning a toolbar
button than what is presented below.
Circle: Click this button to add a circle to the Wall Plot.
Line: Click this button to add a line to the Wall Plot.
Poly Line: Click this button to add a poly (segmented) line
to the Wall Plot.
Curved Line: Click this button to add a curved line to the
Wall Plot.
Arrow: Click this button to add an arrow to the Wall Plot.
Icon Description
Align Left: Click this button to align two or more objects
along a vertical line defined by the left-edge of the last
object selected.
Align Right: Click this button to align two or more objects
along a vertical line defined by the right-edge of the last
object selected.
Align Top: Click this button to align two or more objects
along a vertical line defined by the top-edge of the last
object selected.
Icon Description
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Align Bottom: Click this button to align two or more
objects along a vertical line defined by the -bottom edge of
the last object selected.
Center Vertically: Click this button to align one or more
object(s) along a vertical line defined by the middle of the
page.
Center Horizontally: Click this button to align one or more
object(s) along a horizontal line defined by the middle of the
page.
Space Across: Click this button to evenly space three or
more objects across the page.
Space Down: Click this button to evenly space three or
more objects down the page.
Make Same Width: Click this button to make all selected
objects the same width as the object selected last.
Make Same Height: Click this button to make all selected
objects the same height as the object selected last.
Make Same Size: Click this button to make all selected
objects the same size as the object selected last.
Grid: Click this button to toggle the grid on or off.
Snap-To-Grid: Click this button to create a background
grid on the plot to help position graphs on a plot. When snap
to grid is selected graphs will resize and move to the next
closest grid point.
Grid Settings: Click this button to access the Grid Setting
dialog.
Icon Description
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Working With Wall Plot Composer Objects and Sub-Objects
Wall Plot Composer objects and sub-objects can be configured,
customized, moved, and resized. You must select the object(s) or sub-
object(s) that you want to change the appearance of before you can
change it. For a more complete explanation of what objects and sub-
objects are, refer to “What is an Object?” on page 310 and “What is a
Sub-Object?” on page 311.
Adding an Object to the Wall Plot
1. Select the object you want to add to the Wall Plot. Use any of the
following three methods.
• Object toolbar buttons. Refer to “Using the Object Toolbar” on
page 314 for more information on the Object toolbar. (If the
toolbar buttons are not active, click anywhere on the Wall Plot
page to activate them.)
• Composer > Add
• Selecting an object from the right-click menu. To use the right-
click menu, click anywhere on the Wall Plot page where there is
not already an object.
2. Using the mouse, place the crosshair cursor where you want one
corner of the object to be located. If you are adding an art object
(other than a circle or ellipse), refer to “Adding an Art Object to the
Wall Plot” on page 318. Use this procedure for circle and ellipses.
3. Click and hold the left mouse button as you define the size of the
object.
4. Release the mouse button when the object is the desired size.
Adding an Art Object to the Wall Plot
1. Select the art object you want to add to the Wall Plot. Use one of the
following three methods to add an art object.
• Object Toolbar buttons. Refer to “Using the Object Toolbar” on
page 314 for more information on the Object toolbar. (If the
toolbar buttons are not active, click anywhere on the Wall Plot
page to activate them.)
• Composer > Add
• Select an art object from the right-click menu. If you are adding
a circle or ellipse, refer to “Adding an Object to the Wall Plot”
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on page 318. To access the right-click menu, click anywhere on
the Wall Plot page where there is not already an object.
2. Using the mouse, place the crosshair cursor where you want the
starting point to be. Then, refer to the following:
• Lines: Click where you want to begin the line. Continue to hold
the mouse button as you move the cursor to the end point.
Release the mouse button.
• Polygons: Begin as if you were drawing a line. To add another
segment to the line, click anywhere on the line, and continue to
press the mouse button as you move the cursor where you want
the segment to be. Release the mouse button. The last point will
automatically be joined to the first point.
• Polyline: Same procedure as for polygons except the first and
last points are not joined.
• Curved Lines: Same procedure as for polylines except that the
line segments are curved.
• Arrow: Same procedure for lines except there is an arrow head
at one end of the line.
Selecting an Object(s) on the Wall Plot
Click on the black line outlining the object. The outline will change to
to indicate the object has been selected. To select more
than one object, press the Shift key as you select objects.
Selecting a Sub-Object(s) Within an Object on the Wall Plot
A sub-object within an object is selected by clicking on the sub-object.
The outline will change to to indicate the sub-object has
been selected. To select more than one sub-object, press the Shift key as
you select sub-objects. To select all sub-objects in a group, select the
first sub-object, then press the Alt key when you select the second sub-
object.
Moving an Object(s) or Sub-Object(s) on the Wall Plot
1. Select an object(s) or sub-object(s) that you want to move. Refer to
“Selecting an Object(s) on the Wall Plot” on page 319 or “Selecting
Note: Selecting an object prior to resizing, moving, or customizing...
You must select an object before you can resize, move, or customize it.
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a Sub-Object(s) Within an Object on the Wall Plot” on page 319 for
instructions on selecting objects or sub-objects.
2. Slightly move the cursor until it changes to .
3. Press and hold the left mouse button until the object or sub-objects
is in the desired location. Sub-objects within an object can’t be
moved outside of the object.
Deleting Object(s) or Sub-Object(s)
1. Select an object(s) or sub-object(s) that you want to delete. Refer to
“Selecting an Object(s) on the Wall Plot” on page 319 or “Selecting
a Sub-Object(s) Within an Object on the Wall Plot” on page 319 for
instructions on selecting objects or sub-objects within objects.
2. Press the Delete key. Labels are not really deleted, but are hidden.
Refer to “Using Wall Plot Composer Right-Click Menus” on
page 328 for more information on hiding/showing labels.
Resizing an Object(s) or Sub-Objects(s)
1. Select an object(s) or sub-object(s) that you want to resize. Refer to
“Selecting an Object(s) on the Wall Plot” on page 319 or “Selecting
a Sub-Object(s) Within an Object on the Wall Plot” on page 319 for
instructions on selecting objects or sub-objects within objects.
2. Slightly move the cursor over a box located in the boundary of the
object or sub-objects until it changes to . If you want to
resize the text within an object while you resize the object, press the
Shift key as you resize the object.
3. Press and hold the left mouse button until the object or sub-objects
is the desired size. Sub-objects within an object can’t be resized
outside of the object. To rescale the fonts and line thickness and
maintain size relative to the object box, hold the Shift key down
when resizing an object.
Note: Resizing objects with a specific scale...
You can not resize an object that you have specified a specific scale.
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Placing Object(s) and Sub-Object(s) Relative to Each Other
1. Select an object(s) or sub-object(s) that you want to move relative to
other overlapping object(s) or sub-object(s). Refer to “Selecting an
Object(s) on the Wall Plot” on page 319 or “Selecting a Sub-
Object(s) Within an Object on the Wall Plot” on page 319 for
instructions on selecting objects or sub-object(s) within objects.
2. Click the right mouse button and select Order. Bring to Front
moves the object to the front of all objects that overlap it. Bring
Forward moves the object forward one place when overlapped by
other object(s). Send to Back moves the object to the back of all
objects that overlap it. Send Back moves the object back on place
when overlapped by other object(s).
Aligning Object(s) and Sub-Object(s) on the Page
1. Select an object(s) or sub-object(s) that you want to align on the
page. Refer to “Selecting an Object(s) on the Wall Plot” on page 319
or “Selecting a Sub-Object(s) Within an Object on the Wall Plot” on
page 319 for instructions on selecting objects or items within
objects.
2. Use the Layout toolbar options to align the object on the page.
Refer to “Using the Layout Toolbar” on page 316 for more
information on using the Layout toolbar.
Editing Style, Thickness, and Color
Double-click on any line, and the Properties dialog for the Wall Plot
Composer displays. Use this dialog to edit the style, thickness, and
color.
Exporting Selected Objects
Export the currently selected object(s) to create a library of customized
objects. You can import this library into any plot. The exported objects
appear on the import drop-down menu.
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Designating an Object’s Properties as the Default Setting
1. Customize an object with your preferred line styles, color schemes,
and fonts.
2. Right click and choose the Defaults > Save option.
3. Use the Defaults > Apply option to apply the default properties to
existing objects.
Setting an Exact Graph Size
Make a graph exactly the size you want by specifying both a scale and
a range on the Scale tab of the graphs properties. The graph will be
resized to adhere to the scale and range and will always spring back to
that size even if you try and resize it using the mouse.
Embedding Images on a Plot
Any images used on a plot will get embedded in the.WPC file when the
plot is saved. This means the.WPC file can be used on different
machines without having to copy the images around. The exceptions to
this are logos, which are refreshed based upon the current context. Refer
to “Wall Plot Composer Files” on page 329 for more information.
Changing Object Properties
There are many dialogs that are used to change the properties of Wall
Plot Composer objects and sub-objects. In this section, the tabs
associated with each type of object are listed along with a short
description. For more information about a specific tab, refer to the
online help.
To change the properties of an object or sub-object:
1. Select an object(s) or sub-object(s) that you want to change the
properties of. “Selecting an Object(s) on the Wall Plot” on page 319
or “Selecting a Sub-Object(s) Within an Object on the Wall Plot” on
Note: Defaults for different paper sizes...
Different defaults are maintained for different ranges of paper sizes
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page 319 for instructions on selecting objects or sub-objects within
objects.
2. To access the Properties tabs, right-click and select Properties or
click the toolbar button.
Changing XY Graph Properties
XY graphs can be changed using the following Properties tabs. Not all
tabs apply to all types of XY graphs. Refer to the online help for more
specific information about a tab.
Tab Name Functionality
Analysis Use this tab to specify what is to be displayed on the X and
Y axis of an XY Analysis graph.
Annotations Use this tab to include and to configure the display of
annotations on the 3D and XY Graph Wall Plot Composer
objects. To specify annotations, open a Plan and click the
Plan Comments icon.
Axis & Grid Use this tab to configure the axis (top, bottom, left, and
right) and to control the display of the grid on an XY Graph
Wall Plot Composer object.
Azimuth and
Inclination Labels
Use this tab to include and configure the display of azimuth
and inclination labels on XY Graph Wall Plot Composer
objects. The title of this tab will be either Azimuth Labels or
Inclination Labels depending on the XY Graph selected.
Background Use this tab select a background color and border style,
thickness, and color for many Wall Plot Composer objects.
Casings Use this tab to include and to configure the display of casing
sizes and placement on the 3D and XY Graph Wall Plot
Composer objects.
Errors Use this tab to configure the display of error ellipses on an
XY Graph object.
Formations Use this tab to include and configure the display of the
formation tops on the 3D or XY Graph Wall Plot Composer
objects.
Options Use this tab to configure a variety of items associated with
XY Graph Wall Plot Composer objects.
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Changing Traveling Cylinder Graph Options
Traveling Cylinder graphs can be changed using the following
Properties tabs. Refer to the online help for more specific information
about a tab.
Picture Use this tab to select a picture for display within a Wall Plot
Composer object. You can resize the picture to fit the screen
or by maintaining the aspect ratio. For XY Graphs, you can
apply the picture to the grid area only.
Scale Use this tab to specify the axis scale and range, and to
configure axis location and grid configuration.
Targets Use this tab to include and to configure the display of
targets.
Template Use this tab to display templates on some of the XY Graphs.
TVD or MD Labels Use this tab to include and configure the display of MD and
TVD labels. The title of this tab will be either MD Labels or
TVD Labels depending on the XY Graph selected.
Well Labels Use this tab to specify the location, frequency, orientation,
and other options associated with well labels.
Tab Name Functionality
Background Use this tab select a background color and border style,
thickness, and color for many Wall Plot Composer objects.
Depth Labels Use this tab to specify the location, frequency, orientation,
and other options associated with depth labels
Options Use this tab to configure a variety of items associated with
Traveling Cylinder Graph Wall Plot Composer objects.
Picture Use this tab to select a picture for display within a Wall Plot
Composer object. You can resize the picture to fit the screen
or by maintaining the aspect ratio.
Scale & Grid Use this tab to configure the scale, graph labels, and grid
options.
Well Labels Use this tab to specify the location, frequency, orientation,
and other options associated with well labels.
Tab Name Functionality
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Changing 3D Graph Options
3D graphs can be changed using the following Properties tabs. Refer to
the online help for more specific information about a tab.
Wellpath Selection Use this tab to select the offset wells you want displayed on
the Traveling Cylinder object. The list of selections
available on the tab is based on the offset wells selected
using the View > Offset Designs dialog.
Tab Name Functionality
Annotations Use this tab to include and to configure the display of
annotations. To specify annotations, open a Plan and click
the Plan Comments icon.
Background Use this tab select a background color and border style,
thickness, and color for many Wall Plot Composer objects.
Casings Use this tab to include and to configure the display of casing
sizes and placement on the 3D Graph Wall Plot Composer
objects.
Errors Use this tab to configure the display of error ellipses on a 3D
Graph object.
Formations Use this tab to include and configure the display of the
formation tops on the 3D or XY Graph Wall Plot Composer
objects.
Options Use this tab to configure a variety of items associated with
3D Graph Wall Plot Composer objects.
Picture Use this tab to select a picture for display within a Wall Plot
Composer object. You can resize the picture to fit the screen
or by maintaining the aspect ratio.
Targets Use this tab to include and to configure the display of targets
on the 3D and XY Graph Wall Plot Composer objects.
Wellpath Selection Use this tab to select the offset wells you want displayed on
the 3D object. The list of selections available on the tab is
based on the offset wells selected using the View > Offset
Designs dialog.
Tab Name Functionality
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Changing Data Boxes Graph Options
Data Box objects can be changed using the following Properties tabs.
Refer to the online help for more specific information about a tab.
Changing Geological Columns Graph Options
Geological Column objects can be changed using the following
Properties tabs. Refer to the online help for more specific information
about a tab.
Changing North Arrow Options
North Arrow objects can be changed using the following Properties tabs.
Refer to the online help for more specific information about a tab.
Tab Name Functionality
Background Use this tab select a background color and border style,
thickness, and color for many Wall Plot Composer objects.
Data Box Use this tab to configure what is displayed in a Data Box
object. If you have selected a pre-defined Data Box, you can
change what is displayed using this tab. If you have selected
a User Defined Data Box, you must use this tab to specify
what you want displayed in the Data Box.
Picture Use this tab to select a picture for display within a Wall Plot
Composer object. You can resize the picture to fit the screen
or by maintaining the aspect ratio.
Tab Name Functionality
Background Use this tab select a background color and border style,
thickness, and color for many Wall Plot Composer objects.
Geological
Columns Options
Use this tab to configure the Geological Columns objects.
Picture Use this tab to select a picture for display within a Wall Plot
Composer object. You can resize the picture to fit the screen
or by maintaining the aspect ratio.
Tab Name Functionality
Background Use this tab select a background color and border style,
thickness, and color for many Wall Plot Composer objects.
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Changing Legend Options
Legend objects can be changed using the following Properties tabs.
Refer to the online help for more specific information about a tab.
Changing Text Box Options
Text Box objects can be changed using the following Properties tabs.
Refer to the online help for more specific information about a tab.
Changing Picture Options
Picture objects can be changed using the following Properties tabs.
Refer to the online help for more specific information about a tab.
Picture Use this tab to select a picture for display within a Wall Plot
Composer object. You can resize the picture to fit the screen
or by maintaining the aspect ratio.
Tab Name Functionality
Background Use this tab select a background color and border style,
thickness, and color for many Wall Plot Composer objects.
Legend Options Use this tab to configure many Legend object options.
Picture Use this tab to select a picture for display within a Wall Plot
Composer object. You can resize the picture to fit the screen
or by maintaining the aspect ratio.
Tab Name Functionality
Colors and Lines Use this tab to configure the appearance of lines, polylines,
curved lines, arrow, or text boxes.
Text Box Use this dialog to specify and configure the text you want to
add to the Wall Plot.
Tab Name Functionality
Background Use this tab select a background color and border style,
thickness, and color for many Wall Plot Composer objects.
Tab Name Functionality
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Changing Rectangle, Polygon, or Ellipse Options
Rectangle, polygon, or ellipse objects can be changed using the
following Properties tab. Refer to the online help for more specific
information about a tab.
Changing Line, Segmented Line, Curved Line, or Arrow Options
Line, segmented line, curved line, or arrow objects can be changed using
the following Properties tab. Refer to the online help for more specific
information about a tab.
Using Wall Plot Composer Right-Click Menus
Right-click menus are a convenient way of accessing commonly used
functionality. The content of the right-click menus vary depending on
what the cursor is on when you right-click. Right-click menus are
available for:
� Wall Plot Composer: Use this right-click menu to select an object
for placement on the Wall Plot. You can also use Composer > Add
or the Objects Toolbar to select objects for placement. Also
available on the Wall Plot Composer right-click menu is the Import
option that can be used to import a Wall Plot Export (.wpe) file.
You can also use the toolbar button to import the WPE
file.
Picture Use this tab to select a picture for display within a Wall Plot
Composer object. You can resize the picture to fit the screen
or by maintaining the aspect ratio.
Tab Name Functionality
Background Use this tab select a background color and border style,
thickness, and color for many Wall Plot Composer objects.
Tab Name Functionality
Colors and Lines Use this tab to configure the appearance of lines, polylines,
curved lines, arrow, or text boxes.
Tab Name Functionality
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� Wall Plot Composer Objects: Use this right-click menu to access
many useful configuration features for Wall Plot Composer objects
or sub-objects within an object. You can also right-click on the Wall
Plot Composer to select an object for inclusion on the Wall Plot.
� Wall Plot Composer Art Tools: Use this right-click menu to access
many useful configuration features for lines, polylines, polygons,
curved lines, or arrows.
Wall Plot Composer Files
Wall Plots can be saved. If you create a Wall Plot file using one set of
wells and then reopen the file using the same set of wells, all changes
you made to the plot will be included. If you open the file with a
different set of wells, the layout and settings will be remembered, but
changes you made to labels will not be included.
Plots can be saved WPC (.wpc) files only. Stored in the plot file is:
� File version: To allow tracking changes over time and to maintain
backward compatibility with previous versions of the software.
� Printer and page settings: The Wall Plot Composer will attempt to
select this printer by default when printing or preview printing.
� Colors and symbols: Any colors and symbols used by any offset
wells that are currently selected. When the WPC file is opened,
these settings will be restored in the same offset wells are already
selected. After the WPC file is opened, selecting the offset wells
will not apply the color and symbols settings. The offset wells must
be selected prior to opening the WPC file.
� Plot objects and sub-objects: Including any property changes and
the positions of all labels.
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Chapter
Tools
Overview
In addition to the setup windows for each level of the data structure, you
commonly use a number of additional utilities and resources when
working with COMPASS.
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Geodetic Calculator
The geodetic calculator is a simple tool used to calculate Grid
Convergence and Scale Factor for a given location, assuming a chosen
geodetic system. You can also use it to do quick geographic conversions
and calculate a UTM zone from geographic coordinates. Calculated
results are displayed in the window and can be shared using Windows
Notepad.
The Calculator
The following graphic depicts the Geodetic Calculator.
Geodetic System, Datum and Map Zone
You must select the correct geodetic system before doing geodetic
conversions (latitude and longitude <> easting and northing). The
default system is taken from the current Field.
Some Geodetic Systems have a fixed Datum (e.g. Nigerian Projection
System uses Clarke 1880) while others (e.g., UTM) enable any datum to
be selected. Additionally, some Geodetic Systems have a fixed Map
Zone (e.g., Brunei/Borneo grid = NW Borneo Grid), or enable a
Full selection of Geodetic
Systems and Datums available.
A Geodetic Coordinate ‘System’
comprises the Geodetic
System itself, a Geodetic
Datum or Ellipsoid, and a Map
Zone.
Location may be entered as local
offsets from Site Center, Map
Coordinates, or Geographic
Coordinates.
You can determine appropriate
UTM zone from entered Latitude
& Longitude.
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selection of one or more Map Zones (e.g. Lambert Algerie North &
South).
Select one of the input coordinate types using the radio button, then
enter the position of interest in the coordinate system based on the
following criteria:
Results
Grid Convergence
The angle difference from True North to Grid North for the location.
Scale Factor
The scale factor is the ratio between measured distance on the map and
measured distance on the ground at the location. Even though it is
calculated, Scale Factor is not used to conduct map to local coordinate
conversions unless the COMPASS geodetic system configuration file is
set up to apply it. Scale Factor conversion is normally turned off by
default.
UTM Zone
The geodetic calculator has a UTM Zone button to compute the correct
UTM Zone for the latitude and longitude you enter. This button is only
available when you choose the Universal Transverse Mercator system.
Position Criteria Description
Local to Site Enter the location of interest as local Northings
and Eastings from Site Center.
Map Position Enter Map coordinates based on the Geodetic
System.
Geographic Geodetic coordinates of your location based on
the Spheroid.
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Geomagnetic Calculator
Where the local magnetic field cannot be measured or obtained, the
Geomagnetic calculator enables the local geomagnetic field to be
calculated using a set of Geographic coordinates, a Date, and a
predictive global Geomagnetic model. The calculator is most commonly
used to calculate magnetic declination, which is a required correction for
magnetic survey readings.
The calculated values are not used in any COMPASS calculations.
However, the results appear in most surveying reports and the Site data
block in Wallplot Composer output. A Norths arrow is displayed in the
Status Box reference area which can also be included in a Wallplot.
The Calculator
The following graphic depicts the Geomagnetic Calculator.
The Geomagnetic Calculator can be launched from the Site Setup
window or from the COMPASS toolbar. The geographic coordinates
Location defaults from
current Site. Change it by
retyping, using up/Down
arrows or selecting Field,
Site, Well or User defined
location.
A short Geomagnetism Report is available using the
Windows Notepad feature. This text can be easily
printed or copied to other documents via the Windows
Clipboard.
You can compare the results from
different Geomag models;
however beware of date restrictions
on certain models.
Vertical Depth value can be
entered to calculate geomag field
lower down the wellpath.
Date defaults to current
date, but it can be changed
to compute historical values.
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default to those of the current site, assuming that a site is open with a
geodetic system defined. The date defaults to today, but can be changed
to any date. The geomagnetic model defaults to that selected in Site
Setup.
The Geomagnetic Field can be calculated at surface, or calculated at
different TVDs below the current site. This is a useful feature to gauge
the effect of TVD on declination of surveys taken down the wellpath.
Results
The Geomagnetic field varies slowly in time and can be described as
that of a bar magnet with north and south poles deep inside the Earth,
and magnetic field lines that extend well out in space. Because the field
varies, models are used predict what the geomagnetic field is at a
particular time and place.
The results are in nanoteslas (nT) and degrees (°).
The geomagnetic field can be quantified as total field, dip angle,
horizontal intensity, vertical intensity, and declination. Total field or
total intensity is the magnetic strength, which ranges from about 23
microteslas (equivalent to 23000 nanoteslas or gammas, or 0.23 oersteds
or gauss) around Sao Paulo, Brazil to 67 microteslas near the south
magnetic pole near Antarctica. The angle of the field relative to the level
ground is the dip angle or inclination, which is 90° at the north magnetic
pole. Note dip angle is positive downwards.
Vertical and horizontal intensity are components of the total intensity.
X-North is the component of the magnetic field that is aligned north /
south. Y-East is the component of the magnetic field that is aligned east
/ west. Z-Vertical is the component of the magnetic field that is aligned
with gravity.
Finally, the angle of the horizontal intensity, with respect to the north
geographic pole, is declination. Declination is the angle between where
a compass needle points and the true north pole.
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The following graphic depicts the seven parameters of the Earth’s
Magnetic Field:
Results can be shared with other colleagues or contractors using the
Notepad feature.
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Using the Site Optimizer
When drilling to a number of targets, you can use the Site Optimiser to
determine the optimum site location to minimize the drilling required to
hit all targets defined for the Site. The Optimiser plans a series of 2D
Slant or S wells to each target aiming point. Results are displayed with
the total well drilled, maximum inclination held, maximum measured
depth, and total displacement. You can manually adjust the site center,
or use an optimize function that automatically determines the site
location.
Similar to other tools in COMPASS, the Site Optimiser consists of two
windows:
� Optimiser, which is used to control and view results,
� Viewer, which is used to display the relative positions of the site
center and target locations.
Note: Site Optimizer plans are not saved when tool is closed.
The simple plans Site Optimiser creates to determine the best location are not
saved when you close the tool. When you determine the best drilling location,
click OK to update the Site center or click Cancel to exit without updating the
location.
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Both dialogs come with specific tools.
ViewerOptimizer
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Site Optimizer
The following graphic depicts the Site Optimiser.
Targets
When design constraints are entered, the targets list contains a short
description of the plan to each target. The description includes the target
location, displacement from site center, maximum inclination of the
well, and its MD and TVD.
Design Constraints
This area is used to define which type of well design is used to drill to
each target.
You have two choices:
� Slant well
� Optimum Align using dogleg severity.
The Kick Off field enables you to define a typical KOP. If you are using
optimum align, the optimiser uses the Dogleg entered in the DLS1 field
for Slant wells. Also note that you can increase DLS1 and DLS2 using
The Target List displays the MD, TVD,
and maximum inclination to drill a well
to the target location.
The Summary Statistics display the
worst case directional parameters for all
wells to hit all targets.
The Design Constraints enables the
user to define directional drilling
parameters for Slant and Optimum
Aligned wells to hit targets.
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the Optimiser if a plan to a particular target is not possible using the
parameters entered.
The optimiser assumes a well is used for each target in the site list; no
wells are planned that intersect multiple targets. Also note that all wells
are drilled in a vertical section—they are 2D.
Site Centre
This area enables you to manipulate the site center location. There are
three ways to change the site location:
� Type in the new Centre Location map coordinates.
� Click one of the buttons to move the site north, south,
east or west by 100 map units.
� Click the Optimiser Viewer , then move the cursor and click
the left mouse button on the required location.
When you decide on a location click Set Site Centre to assign the
current coordinates to the current Site.
Click Optimize to sums the target Eastings and Northings, and divide
both by the number of targets to provide a first-guess start location.
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Optimiser Viewer
This graph is a plan view of the site targets and the site center connected
by lines that represent each plan. The optimiser view appears
automatically when site optimiser is shown.
The site optimiser viewer enables you to toggle between UTM (Map)
and Local coordinates display.
You can change the site center by entering the coordinates in the edit
controls, or by clicking the graph when it is displays Map coordinates.
Results
As you move the site location, COMPASS reports the following:
This... Means...
Maximum Angle The maximum inclination of any wellpath.
Average Angle The sum of the final inclinations divided by the
number of targets.
Maximum MD The maximum measured depth to any of the
targets.
Total Measured Depth The sum of the measured depth to all the
targets.
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The maximum results also reports which target required this worst case
value.
Maximum Displacement Horizontal displacement to the furthest target.
Total Displacement The sum of all the horizontal displacements to
all targets.
Centre Location The origin for the well plans.
Kick-off The depth at which each wellpath launches.
Build Rate The build rate for kick-off.
This... Means...
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Chapter
Theory
Overview
This section of the training manual discusses in detail some of the theory
referenced in other sections of the manual. In addition, there is an
introduction to directional drilling.
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Introducing Directional Drilling
This section briefly introduces directional drilling and survey
measurement techniques, and describes the hardware technology related
to use of COMPASS. This section is not intended as a complete
reference and there are numerous, more thorough publications that deal
with this subject.
Directional drilling is the science of drilling a well so that its trajectory
follows the planned path to one or more drilling and/or geological
targets. The well must be drilled precisely using the planned directional
parameters designed for the well. If the well steers off course, the
trajectory must be redesigned and drilled to get the well back on track.
Different planning techniques enable wells of varying complexities to
be planned. Different tools enable the well to be drilled and surveyed so
the trajectory drilled is physically as close as possible to that of the plan.
Origins
Directional drilling has always been a part of drilling. In the early days
of drilling at Spindletop, Texas, resourceful drillers put wooden wedges
(Whipstocks) down wells to deviate them towards nearby gushers. This
practice was known as poaching. To prevent this, laws were enacted that
required wells to be positioned within a lease boundary, and wells had
to be inspected for deviation by the Texas Railroad Commission and
other bodies.
The same methods of deviation and measurement enabled wells to be
deviated under obstacles, such as cities, lakes, seas, mountains, shallow
gas, and pipelines. Sidetracks are wellpaths intentionally deviated from
the original hole, which are used to get past fish (lost drill string), correct
unwanted deviation, or reuse an old hole to reduce costs.
Blowout relief wells started in the 1920’s and required precision control
to drill the relief well to within a few feet of a blowout well. Early survey
instruments were developed to meet the requirement to know the exact
trajectory of both blowout and relief wells. When the relief well was
determined to be close to the blowout well, cement was pumped to plug
the formation and control the pressure. In modern relief wells, magnetic
ranging methods are used to accurately position the well close to the
blowout.
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Platform Drilling negates the requirement for additional platforms. A
single template underneath the platform is used to access a number of
locations within a reservoir. Deviated wellpaths permit tapping an
extended area of the reservoir from a compact drill site.
Salt Dome drilling is performed to access traps that form on the
upthrown side of the plug. Drilling can be problematic due to plastic salt
deforming casing and high pressure gas at shallow depths. Sidetracks
are made to re-use wells from depleted zones and to drill new ones.
Planned and unplanned deflections are called doglegs. Bit Walk is a
natural tendency for BHAs to steer off course due to formation and BHA
effects. Planned well trajectories can be corrected for this effect to keep
the well on target.
The following graphic depicts the origins of Directional Drilling:
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Early Means of Directional Control
Oriented Drilling
Directional drilling began with the use of devices such as whipstocks or
techniques such as jetting, rotary assemblies to maintain course, and
wireline steering tools to orient and survey.
Whipstock is the name of a wooden wedge that was the first widely-used
deflection tool for changing the wellbore trajectory. It was run and
oriented on drill pipe and the drill bit was deflected off it, provided the
whipstock was harder than the formation. Use of a whipstock was
problematic because a fill in the hole could seriously impede its
performance. Also, much experience was required to use this method
effectively.
The fulcrum and pendulum bottom hole assemblies are mechanical
methods of increasing or decreasing hole angle once an angle is built.
All BHAs cause a side force at the bit that makes the bit build, drop, or
hold angle and turn to the right or left. BHAs can be designed to provide
a desired performance. This technique relies on precise stabilizer
placement and blade diameters that are used to stand-off and pivot the
collars and bit. This functionality, used with the natural turning
characteristic of different bit types, provides drillers with three-
dimensional, rotary, and directional control.
Keeping the well vertical is very difficult in areas of dipping or hard
formations. The weight applied to crush rock at the bit buckles the pipe
and causes deflection into the dip. Heavy collars and pendulums are
used to counteract these trends.
An example is ‘Oklahoma measured depths’ which was an early study
to determine the pipe depth required to reach top reservoir. Some wells
required 10-50% more pipe to reach the reservoir in so-called vertical
wells. This was because hard Okie formations required much weight to
be drilled. The large compressive forces caused buckling in the drillpipe
which caused the drillstring to be deflected.
Jetting is used in soft formations (gumbo) where one nozzle in a tri-cone
bit is enlarged and oriented to create a rathole, into which the string is
dropped. The technique has been very successful in the Gulf of Mexico,
but has not had much success in the North Sea. Jetting uses the hydraulic
energy of the drilling fluid to erode a hole along a given azimuth. The
string is dropped into the rathole.
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This jet and drop procedure is performed for 3 to 6 ft. without rotating
to establish the new direction. Rotary drilling then proceeds until a
survey is taken to verify the new wellbore trajectory.
This technique is dependent on the formation being drilled. Weakly
cemented sandstones and oolitic limestones prove good candidates,
while very soft or hard formations fail due to the jet blowing away too
much hole in soft formations and not having sufficient power to make
new hole in hard formations. The primary advantage of jetting is that it
can be performed with the same BHA used to drill.
Survey Measurement
The wellpath trajectory is determined by measuring the inclination and
direction at various depths. Early measurement tools included the acid
bottle and punch card, which were used to record inclination in order to
indicate whether the trajectory had deviated. These tools were run on
slick-line (steel wireline). Hydrofluoric acid was poured into a glass
bottle and etched the bottle at the angle at which it came to rest. The
punch card technique was the basis for the TOTCO tool used for
inclination measurement.
Magnetic and gyroscopic tools are used to record inclination and
direction. They use either a single or multi-shot timed camera or
sensitized paper to record stations for deviated wells. Gyros are usually
run on a conductor cable, which supplies power and can be used to
transmit readings to the surface. Other gyros are battery-powered and
are run on a wireline inside casing. Magnetic multi-shot tools are run on
a slick-line, sand line (braided cable), or dropped inside non-magnetic
collars and brought back to surface as the string is tripped.
The muleshoe ensures that the single shot survey tool is consistently
located inside the bottom of the BHA relative to the bent sub, jetting bit,
whipstock wedge, undergauge stabilizer blade, or other tool used to
orient the BHA. As the survey tool lands in the BHA, a stub in the
muleshoe landing ring (in pipe) draws the recess in the survey tool spear
point round so that the tool seats in the direction of the tool face. For
quality control, a lead slug is seated in the recess to indicate a good
survey orientation. Marks in the slug indicate that the landing ring had
seated right into the muleshoe recess.
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The following graphic depicts the early means of directional control:
Modern Directional Drilling
During the 1970’s, directional drilling requirements escalated on
platforms designed to access large parts of the reservoir. Drilling at
these sites became more complex as the fields matured and wells were
safely directed around existing producing and injecting wells. During
the 1980’s and 90’s, directional drilling techniques and equipment
improved dramatically due to requirements to drill a large number of
horizontal wells though fractured limestone reservoirs to increase
production, instead of vertical wells. The Austin Chalk in Texas and the
Cretaceous chalks in the North Sea were driving areas of this
cost-effective technique.
Extended Reach Drilling (ERD) wells are defined as those wells with
departures that exceed twice the well TVD. Different classes of ERD
well have evolved based on increasing Reach/TVD ratios. These include
conventional directional drilling (<2.0), ERD wells (>2.0), and severe
ERD wells (>3.0).
Modern equipment and techniques can drill wells with 10km stepouts at
only 1.5km depth. The best example is Wytch Farm in southern England
where the Sherwood Sandstone reservoir underlies Poole Bay, which is
environmentally protected. Parts of the target are problematic in that the
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reservoir dips onshore, requiring the wells to hit the target downdip,
build, and drill up through the reservoir. These extended wells have been
used as a test site for some of the emerging technologies described in
this section. Even greater ERD wells are being drilled all the time.
Horizontal Wells were pioneered in fractured chalk reservoirs where
vertical wells are uneconomic, because they fail to hit vertical fractures.
Examples include Farmington (short radius), Austin Chalk (medium
radius) and offshore Denmark (long radius). Horizontal wells are now
used in reservoirs where greater life and productivity can be expected
from fewer wells by limiting Water and Gas coning. The economic
success of these wells has resulted in horizontal wells becoming the
norm. The question now is ‘why drill a vertical well?’
Heavy Oil projects (Alberta, Canada) require steam injection from
horizontal wells to warm up the viscous oil and make it mobile so that it
flows into an adjacent parallel wellbore—this is an example of an
Enhanced Oil Recovery (EOR) method. One well is drilled for
production and a second steam injection well is drilled 10/20’
underneath using magnetic ranging from the MWD to the magnetized
casing of the top wellpath. The hot steam from the injection well reduces
oil viscosity, enhancing oil flow into the overlying producer.
Multi-lateral wellpaths are drilled from the same well. Laterals are
planned side-tracks where each path is selectively available to
completion equipment.
River crossing is where a hole is drilled under a river to carry a pipeline
or cable. The hole is drilled and widened using a mining rig on a truck
and deviated up to a target location. Then the pipeline is attached to the
bit and pulled back through.
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The following graphic depicts modern directional drilling techniques:
Mud Motor
The mud motor is the workhorse of modern directional drilling,
representing a major advancement in directional control. First employed
in the oil field by Dynadrill (Smith, Halliburton, now Pathfinder) in
1968 as a directional tool, Positive Displacement Motors (PDM) offer
greater torque and better pressure feedback than turbines. Drilling with
motors is easier because the surface standpipe pressure reflects motor
torque, which in turn can reflect weight on bit (WOB). As motor torque
increases, standpipe pressure increases and vice-versa. Therefore, the
directional driller uses standpipe pressure to advance the bit by
controlling torque. If the bit stalls you get an increase in pressure.
The motor is composed of four standard sections:
� The Dump Sub is used to divert mud so that the roughnecks don’t
get wet feet. It is used to bypass the fluid from the motor while the
tool is tripped into and out of the hole. Essentially it enables the
drillstring to fill with mud from the annulus while tripping in, and
enables the drillstring to drain while tripping out—this prevents it
from flowing out onto the drillfloor when a connection is made.
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When the pumps are started, the fluid forces a piston down, closing
the bypass ports, directing fluid through the motor.
� The Power Section converts hydraulic horsepower into mechanical
horsepower, resulting in drill bit rotation. It consists of two parts,
the rotor and the stator, that when assembled form a continuous seal
along their contact points. The rotor is an alloy steel bar shaped into
a helix and is specially coated in chrome to reduce friction, wear
and corrosion. The stator is a length of tubular steel lined with an
elastomer compound shaped into a helix to mate with the rotor.
PDMs use a reverse application of the Moyno pump principle to
generate power from the mud stream. Slugs of mud are driven
through slots in the rotor/stator, generating torque, which causes the
rotor to cycle backwards through the grooves in the stator
(epicyclical motion). Different rotor/stator lobe ratios (1/2 5/6 9/10)
are used for more power and lower speed. The most common PDM
is a half-lob motor where the rotor has one lobe and the stator two.
PDMs always have 1 more lobe in the stator than the rotor; this
results in a progressive series of cavities for the fluid to flow
through. The pressure of this fluid causes the rotor to rotate. Torque
is then transmitted to the Universal Joint.
� A Universal Joint forms the coupling assembly, which converts the
epicyclical motion of the rotor into rotation at the drive shaft, which
is connected to the bit. It is either a U Joint (Car FWD) or a solid
piece of Beryllium Copper.
The Bent Housing was originated in 1982. Previously a bent sub was
used above the motor. The bent housing allows the whole motor to
be rotated to drill straight, or oriented from surface to drill at an
angle. Bent housing angles are now adjustable.
� The Bearing Assembly supports the motor drive shaft that transmits
drilling thrust which turns the bit. It consists of on- and off-bottom
thrust bearings and radial bearings. Of all the components in a mud
motor, the Bearing Assembly is most exposed to harsh conditions.
Controlled curved wellpaths are drilled using a sequence of
curved/oriented and straight/rotating sections. The bend is always
over- designed by 25-50%. The Stabilizer on the bearing housing is
used to balance the bit and the bend for optimum direction control.
MWD data will tell the Directional Driller which way the bend is
pointing, and the inclination and azimuth of the well heading.
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The following graphic depicts the Mud Motor:
Measurement Systems
Accurate knowledge of wellbore position is important to:
� Optimize the recovery from a reservoir by strategic positioning.
� Build an accurate 3-dimensional map of reservoir surfaces.
� Enable the well to be relocated in the event of an underground
blowout.
� Prevent loss of wells and damage caused by inter-well collisions.
Modern wellbore surveying tools to achieve these objectives include
MWD and Gyros.
Magnetometers are the primary measurement method used while
drilling. The MWD and Multi-shot tools have triaxial magnetometers
and accelerometers. Magnetic surveys are affected by variations in the
earth's magnetic field and by steel from the drill string; they require
special non-magnetic drill collars to be spaced about the survey tool.
Gyroscope surveying is used to obtain more accurate logs. Gyros are
normally run inside casing, although some gyros have been adapted for
pump down and MWD.
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The rate gyroscope has become the standard in the business; it was
developed for cruise missiles. It uses one fixed axis gyro, with gimbal
axes that are held steady by electro-magnetic resolvers. The current
required to prevent swing indicates the rate of turn of the assembly.
These gyros are sufficiently sensitive to pick up the earth’s motion. This
is called gyrocompassing. The initial angle of the tool is detected, and
the sensors then detect movement as the tool moves down the wellbore
on wireline. The movements are integrated into angles and then into
positions.
Because gyros are generally more accurate than magnetic surveys, they
are typically used to correct the wellbore trajectory as calculated from
the magnetic survey data. Magnetic surveys when compared against the
plan can indicate that the well was not drilled to the plan, resulting in
some serious discussion between drillers and geologists. The solution is
to run a gyro and recalculate the wellbore trajectory to see how it
compares against the plan.
The following graphic depicts Magnetic and Gyroscopic Systems:
Measurement While Drilling
MWD tools are instruments that signal the surface with information
about the wellbore and formation at the drill bit. The first application
was directional information (Inc/Azi), which replaced the existing
single-shot instruments.
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In the early 1980’s, formation information was available that included
short normal resistivity and natural gamma ray tools. Recent
developments include sensors that measure formation acoustic velocity
(sonic) and provide electrical images of dipping formations. These types
of tools are called Logging While Drilling (LWD), because the quality
data they provide results in equivalent wireline runs no longer being
required. Tools include sensors that measure Temperature, Neutron
Porosity, Density, Pressure, Vibration, etc.
Additional information provided by MWD systems include downhole
WOB, downhole pressure at bit (PWD), drillstring dynamics data
(vibration), neutron porosity, bulk density, and ultrasonic caliper
measurements. This type of information is used to aid geo-steering.
MWD tools typically consist of a power system, telemetry system,
directional sensor, and formation measurement tools.
� Power is supplied to the tool by turbine or batteries. Batteries can
supply tool power without drilling fluid circulation. Turbine energy
is abundant as it is supplied by fluid flow.
� The Telemetry equipment transmits data back to surface. The
signals are sent via mud pulses, which are interpreted by a pressure
transducer in the stand pipe at the surface.
An example is negative pulse, made by diverting mud from the pipe
to the annulus; it reduces the pressure in the stand pipe. Pressure
pulses are slow. A single pulse takes less than 1 second to transmit.
A digitized angle (Toolface) can take 10-20s to transmit in digital
form.
Positive pulse is also widely used, where the pulse is caused by a
valve restricting flow in the pipe. Both the negative and positive
mud pulse systems use a solenoid driven by a bank of capacitors to
drive the valve. Other methods for signalling the surface have been
tried, such as cable in the pipe (wears out quickly) and radio
transmission (VLF is used but limited by depth).
� Directional survey information is detected by triaxial
magnetometers (electronic compass) and triaxial accelerometers
(electronic plumb bob).
� Geophysical traces are transmitted for geosteering, These are the
Gamma Ray detector (a Geiger counter) and Resistivity (via
electromagnetic wave coils).
� At surface the pulses are converted into log data, which is made
available at the rig floor in terms of dial readings and to the
operator in the form of logs. Log plotting requires a depth tracking
system and computer software.
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The following graphic depicts the MWD at Rigsite:
Inability to steer mechanically while rotary drilling resulted in the
design and implementation of Variable Blade Stabilizers (VBS) also
known as Adjustable Gauge stabilizers (AGS). These tools are designed
to enable blade diameters to be changed while drilling.
These tools, along with other fixed-gauge BHA stabilizers, are used to
change the build and drop tendency of rotary and steerable BHAs with
a simple pumps-on/pumps-off procedure. This enables BHA steering
tendency to be changed to downhole without having to trip the
assembly.
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Other benefits include improved hole cleaning, due to continuous
rotation of the drill string, and torque/drag tortuosity reduction by
limiting dogleg severity.
Emerging Technologies
A number of new technologies are being employed in directional
drilling to enable extended reach or designer well trajectories to be
achieved.
Coiled Tubing/Underbalanced Drilling
Coiled Tubing (CT) rigs were originally developed for workover
operations inside existing wells, but have now been adapted for
sidetracking and drilling. CT rigs can drill short length wells (1500’
horizontal) at lower cost and time than a conventional drilling rig (with
a smaller footprint). The coiled tubing (2” steel) is coiled onto a drum
and fed into the wellbore through an injector with spools that can push
or pull the tubing into the hole. The standard steering combination of
bent mud-motor and MWD has been modified for CT with the addition
of a ratchet indexing device for orienting the motor bend. This is used
because CT cannot be rotated for orientation.
In the Underbalanced Drilling (UB) method, the drilling fluid is made
less dense than the formation fluid inside the reservoir. As a result, the
formation fluid flows into the wellbore. This is desirable because if the
drilling mud overbalances pore pressure, it will invade the reservoir pore
space and reduce permeability. Reduced permeability results in reduced
formation productivity, particularly in horizontal wells where the
reservoir is subject to longer contact times with the drilling fluid, and
open hole completions are more prevalent.
In addition to reducing formation invasion, underbalanced drilling
results in reduction of drilling time due to increased ROP, increased bit
life, and less chance of differential sticking. In normal drilling, lower
mud densities are avoided because pressure problems (blowouts) will
occur which can be difficult to control.
In UB drilling the pressure can be regulated with a special blow-out
preventer and choke at surface. Fluid densities can be reduced by foam
drilling or injecting nitrogen into the drilling fluid. Special equipment is
used at the surface for solids separation and cuttings sampling.
A major drawback with the technique has been the inability to use
MWD—and therefore geosteer—due to the presence of compressible
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gas in the annulus which prevents mud pulse systems from transmitting
back to surface. Electro-magnetic tools (EMT) have solved this problem
for shallow wells enabling direct transmission back to surface. Depth
and temperature restrictions in addition to formation restrictions have
limited the use of EMT, though repeaters/transmitter technology seems
to enable EMT tools to be used at deeper depths.
The following graphic depicts the Coiled Tubing Rig and
Underbalanced Drilling:
Multi-Laterals
Planned multi-lateral (ML) wellbores are now a part of modern
completion practices. Lateral wellbores allow simultaneous production
from two or more zones without the cost of the extra upper wellbore and
surface equipment. Second and subsequent wellbores can be drilled at
30% of the cost of the original well. This method only suits reservoirs
that have good mechanical stability.
ML wells comprise a parent wellbore with one or more secondary
wellbores (laterals), all of which produce or inject fluids or provide
information. They are classified based on the junction mechanism
between the parent and sibling wellbores.
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Whether the junction is open or closed, or whether the tubing or casing
is installed across the junction determines a ML well’s classification. A
common classification scheme contains six variants with increasing
complexity:
The lateral wellbore shown below (Level 3) is constructed by installing
casing in the primary wellbore with a window joint positioned and
rotated in the desired direction. A protective sleeve is removed and a
drilling whipstock is oriented and installed. The window is opened with
a milled tooth bit run on a steerable motor.
Once the lateral is drilled, the junction is cased off with a short liner, the
section of the primary wellbore is washed over and recovered. Drilling
of the lower lateral is then performed through the primary wellbore.
Re-entry into the upper lateral can be performed at any time by installing
a retrievable workover whipstock.
This classification... Has these features...
Level 1 No zonal isolation, such as openhole sidetracks.
Specific branch access is difficult, sometimes
impossible.
Level 2 Cased and cemented parent wellbore with a milled and
slotted liner in the sibling, but provides no zonal
isolation or pressure integrity across the junction.
Level 3 Contained cased and cemented parent and sibling
wellbores with cement or epoxy at the junction. The
junction provides no zonal isolation, and cannot sustain
a differential pressure greater than the formation
fracture pressure.
Level 4 Same as Level 3 but contains cement at the junction
designed to provide pressure support greater than the
fracture pressure. Packers in the parent wellbore
provide zonal isolation by being placed on both sides of
the sibling.
Level 5 Achieves full zonal isolation using a downhole
deflector at the junction and a system of packers in both
parent and sibling wellbores. This enables production
tubing to be mechanically sealed.
Level 6 Uses mechanical splitters to achieve full zonal isolation
along both branches.
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The following graphic depicts the Multi-Lateral Level-3 Completion:
ML wells can also be classed based on their relative geometry. Different
types include:
� opposed dual laterals
� stacked dual laterals
� multi-laterals
� branched multi-laterals
� splayed multi-laterals
� forked dual laterals
Rotary Steerable Systems
Rotary steerable devices (also known as Steerable Rotary Drilling -
SRD) enable inclination and azimuth correction during rotary drilling.
The concept was first introduced in 1991 by Camco. There are currently
several rotary steerable systems in an expanding market. A number of
different types of systems are being tried.
Rotary steerable systems offer considerable advantages over the
steerable mud motor system:
� Drillstring torque and drag should decrease, resulting in less
tortuous wellbores. This should reduce stuck pipe, and make
workovers and completions easier.
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� Drilling in rotary mode should reduce bit walk.
� ROP should increase 50-100% by enabling bits to be selected for
performance reasons rather than steerability.
� The number of trips required to directionally drill a well should
decrease.
� LWD data quality should improve due to drilling in rotary mode as
well as because the data is obtained closer to the bit. Drilling course
corrections can be made earlier.
� Cuttings transport is better in rotary mode resulting in easier hole
cleaning, less chance of forming cuttings beds, and getting stuck.
� Fewer wiper runs are required (smoother wellbore, less cuttings
beds, and so on).
� Dogleg severity and wellbore spiralling should decrease, resulting
in easier completions.
� Steering should enhance production by keeping the well within the
reservoir.
In comparison, mud motor systems are slow when steering because the
drill string is not rotating and the string will pick up friction and cuttings.
The resultant extra drag becomes so great that the motor becomes
unsteerable, especially if the pipe buckles. A rotary steerable system
will drill faster and farther. They do not offer the range of radii of
motors; therefore they are best suited to extended reach wells.
A rotary steerable device consists of two sections:
� The bias unit is located immediately above the bit. It has three
actuator pads which can be operated in synchronization with bit
rotation in order to provide a lateral displacement in a constant
direction and hence steer the well. The pads are operated
hydraulically using the drilling fluid, and are controlled by a rotary
valve that is mechanically connected to the control unit.
� The control unit is mounted inside a non-magnetic drill collar and
contains a directional sensor package, roll sensors, and control
electronics.
The example below (a hybrid of three designs) has a non-rotating
stabilizer body with three buttons on hydraulic pistons in each blade.
Pressurized oil is driven through a rotating valve to one blade’s pistons.
This imparts thrust to the wall, which by reaction will drive the bit in the
opposing direction, causing it to drill laterally by side cutting.
The rotating valve determines which direction the thrust moves. The
valve itself is driven by an electric stepper motor at to a position which
is synchronized with the rotation detected by a Hall effect transistor.
An oil pump is driven by the rotation movement.
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The following graphic depicts the Hybrid Rotary Steerable Device:
Geo-Steering
Geo-steering is directional steering within the close confines of a
payzone. Wellpath adjustments are made based on real time geological
and reservoir data, in addition to drilling observations. The goal is to
maintain a bit position at an optimum depth near the top of a producing
formation.
Geo-steering enables the planned wellpath trajectory to be evaluated
against the geological model as the well is drilled. The planned build
trajectory may be compromised by inaccurate depths from seismic data,
resulting in the formation tops coming in higher or lower than expected.
Formation markers are detected by Gamma/Resistivity sensors while
drilling the well. The planned trajectory is adjusted to any changed
formation tops to ensure that the well meets it geological requirements.
Steering in the payzone is achieved by watching the petrophysical
sensors for signs of the producing formation, and steering away from
poor formations. Shales and non-productive formations have high
gamma counts (radioactivity) and low resistivity. Productive formations
are ideally clean of radioactive clay minerals, and therefore show low
gamma counts and high resistivity (especially in oil/gas zones).
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Geo-steering equipment consists of detectors near the bit which provide
faster reaction times than sensors located 40’ to 80’ behind the bit. This
enables thinner zones to be drilled with confidence. In a thick productive
zone, other indicators may be used, such as examining cuttings from the
shale shakers, looking for microfossils in limestone, or evaluating
hydrocarbon returns at surface. These measurements can be more
immediate if ROP is low through the reservoir.
The following graphic depicts Geo-Steering Equipment at the Bit:
To maintain quick reaction times, geo-steering is a team effort requiring
close coordination between the driller, the directional driller, MWD
operator, and the geologist interpreting the formations.
With a typical ROP of 30ft/hr, the engineers have two data points per
foot on which to interpret the well against the predicted
geological/petrophysical model. Log curves must be compared and
interpreted against predicted responses to ensure that the well is drilled
to its planned target. These interpretations are fed back to the directional
driller and adjustments are made to the well trajectory where necessary.
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The following graphic depicts the geosteering as a team effort at the
rigsite:
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Survey Calculation Methods
You use survey calculation methods to calculate the final wellbore
position of a second measurement station that is deeper than a first
station, using the position and vector (inclination and azimuth) of the
first station, the vector of the second station, and the measured distance
between the two. Working down the wellpath, a survey calculation
method enables you to determine the total wellpath trajectory.
COMPASS offers four survey calculation methods.
• Minimum Curvature
• Radius of Curvature
• Average Angle
• Balanced Tangential
This setting is the company's preferred calculation method and cannot
be overridden in the Survey module except for Inclination-only surveys.
The following graphic depicts Wellpath Trajectory Calculation
Parameters:
Vertical Section View
TVD
East
V.SectionTVD
North
DVD
3 Dimensional View
Compass Survey Calculation
DMD
Plan View (horizontal)
RI (radcur)
I2
I1
A1
A2
DNS
DEW
R (mincur)
Tangents to Sphere
Great Circle
DVS
East
RA (radcur)DL
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General Parameters
• TVD2 = TVD1 + ∆TVD
• NS2 = NS1 + ∆NS
• EW2 = EW1 + ∆EW
Input Parameters
• MD1 = measured depth of top point (ft./m)
• MD2 = measured depth of bottom point (ft./m)
• I1 = inclination of top point (rad)
• I2 = inclination of bottom point (rad)
• A1 = azimuth of top point (rad)
• A2 = azimuth of bottom point (rad)
Output Values
• ∆NS = change in North/South position between points 1-2 (ft./m)
• ∆EW = change in East/West position between points 1-2 (ft./m)
• ∆TVD = change in true vertical depth between points 1-2 (ft./m)
• DL = Dogleg Angle (rad)
• DLS = Rate of Change of angle with depth in 3D space
• Build = Rate of change of inclination with depth (may be Drop)
• Walk = Rate of change of azimuth with depth (also called Turn)
• ∆MD = MD2 - MD1
• DL = ArcCos (Cos(I2 - I1) - Sin(I1) * Sin(I2) * (1.0 - Cos(A2 - A1)))
• DLS = DL/∆MD
• Build = (I2-I1) / ∆MD
• Walk = (A2-A1) / ∆MD (Note: azimuth is normalized for > 180
degree turns)
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Calculation Methods
Minimum Curvature (also called Circular Arc)
This survey calculation method is most widely adopted in the oil
industry. The path taken conforms to the tangential arc in the 3D sphere
shown in the diagram on the previous page.
Calculate RF (Minimum curvature ratio factor) Smoothing Factor
• if (DL < 0.0043633 rad) RF = 1.0
• if (DL >= 0.0043633 rad) RF = (2.0 / DL) * Tan(DL/2.0)
Note: (0.0043633 rad = 0.25 deg)
• ∆NS = ∆MD/2.0 * (Sin(I2)*Cos(A2) + Sin(I1)*Cos(A1)) * RF
• ∆EW = ∆MD/2.0 * (Sin(I2)*Sin(A2) + Sin(I1)*Sin(A1)) * RF
• ∆TVD = ∆MD/2.0 * (Cos(I2) + Cos(I1)) * RF
Radius of Curvature
The Radius of Curvature survey calculation produces slightly different
results from the Minimum Curvature method. The path taken conforms
to the two separate radii in the plan and section views shown in the
COMPASS Survey Calculation diagram. It does not have a single 3D
radius, and hence dogleg severity (DLS) changes over the course length.
• ∆NS = ∆MD * [Cos(I1) - Cos(I2)] / (I2 - I1) * [Sin(A2) -
Sin(A1)] / (A2 - A1)
• ∆EW = ∆MD * [Cos(I1) - Cos(I2)] / (I2 - I1) * [Cos(A1) -
Cos(A2)] / (A2 - A1)
• ∆TVD = ∆MD * [Sin(I2) - Sin(I1)] / (I2 - I1)
Average Angle
Average angle is a survey calculation easily adopted to hand calculation.
The differences between it and the above two methods are very small.
• ∆NS = ∆MD * Sin((I1+ I2)/2)*Cos((A1+ A2)/2)
• ∆EW = ∆MD * Sin((I1+ I2)/2)*Sin((A1+ A2)/2)
• ∆TVD = ∆MD * Cos((I1+ I2)/2)*Cos((A1+ A2)/2)
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Balanced Tangential
The balanced tangential survey calculation method is essentially the
Minimum Curvature method with RF=1. It is considered to be the least
accurate of these four methods.
• ∆NS = ∆MD/2.0 * (Sin(I2)*Cos(A2) + Sin(I1)*Cos(A1))
• ∆EW = ∆MD/2.0 * (Sin(I2)*Sin(A2) + Sin(I1)*Sin(A1))
• ∆TVD = ∆MD/2.0 * (Cos(I2) + Cos(I1))
Inclination Only
The inclination only method is included in COMPASS to handle
inclination-only measurement tools like TOTCO. It calculates vertical
depth in the same way as Radius of Curvature or Minimum Curvature,
but does not calculate the North and East dimensions.
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Geodesy
Geodesy is the science of measuring the earth's surface. The Earth is
round (sort of) and maps are flat. A geodetic system enables you to
convert geodetic coordinates (angles on a round earth—latitude/
longitude) to map coordinates (distances on a flat map—easting/
northings). To do this you must know the system, the datum (ellipsoid),
and the zone.
System
A geodetic system is one or more map projections covering adjacent
parts of the globe. A system can comprise one or more zones. If you do
not know the geodetic system for your area, or if you have no need to
convert between geodetic and map coordinates, select Flat Earth. By
selecting Flat Earth you disable conversion between geodetic and map
coordinates throughout the Field. Otherwise, select the geodetic system
agreed on for use in an area.
COMPASS ships with a pre-defined set of geodetic systems that cover
the majority of systems used in the oilfield. Certain locations require
additional or customized geodetic systems. These are easily added in
COMPASS as geodetic configuration files, which are commonly
constructed by your regional Landmark Support Office.
Datum
A datum or ellipsoid is essentially a mathematical model that best
represents the actual shape of the Earth’s surface in a given area. The
Earth’s surface is generally geometric like an American football or
rugby ball. However, it is an irregular, slightly flattened sphere—a
geoid. We cannot compute geodetic conversion on a geoid, so we
assume the earth to be an ellipsoid. Because the earth's surface is
irregular, different shaped ellipsoids better represent different parts of
the globe. The size and shape of the ellipsoid varies depending on part
of the globe mapped.
Regional geographic organizations, and even oil operator survey
departments recommend which geodetic system and ellipsoid to use for
a given operating area.
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Map Zone
A geodetic system can contain one or more map zones. Each zone maps
a different area. Following are three examples of geodetic systems
shipped with COMPASS:
US Stateplane Coordinate System 1983
This system maps the United States. It is a combination of
Transverse Mercator and Lambert Projections and comprises 124
zones. Most States have more than one zone—Alaska has ten zones,
Texas has five, Maryland has only one. Unlike the UTM projection,
just one ellipsoid is used for the entire system—GRS 1980.
Universal Transverse Mercator
The UTM system maps the entire world by dividing it into 60 zones,
each 6° of longitude wide, extending up to 84° N and S. When the
UTM system is selected COMPASS makes all datums available and
lets you select any one of the 60 zones north or south.
The diagram below depicts a UTM zone covering both southern and
northern hemispheres. Two reference points are plotted, one in the
West side of the Northern Hemisphere, the other in the East side of
the Southern Hemisphere. Note that convergence (angle from True
North to Grid North) for both points is negative. In the other two
quadrants (NE & SW), convergence is positive.
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UK National Grid
This system maps the United Kingdom, has one zone, and is based
on the Airy 1949 ellipsoid.
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Geomagnetism
What is the Magnetic North Pole? The Earth's core has remained molten
due to heat from ongoing radioactive decay. Convection currents
flowing in the outer core generate a magnetic field, but the poles of this
field do not coincide with north and south poles (the axis of rotation of
the Earth). In early 1998, the average position of the modeled north
magnetic dipole (according to the IGRF-95 geomagnetic model) was
79.5° N, and 106.3° W, 40 kilometers north-west of Ellef Ringnes Island
in the Canadian Arctic. This position is 1170 kilometres from the true
(geographic) North Pole.
It is generally believed that a compass needle points to the magnetic
north pole. Because the geomagnetic field is the effect of complex
convection currents in magma composing the Earth’s core, the local
field must be described as several dipoles, each with a different intensity
and orientation. Because of this, the compass needle actually points to
the sum of the effects of these dipoles at a given location. In other words,
the needle aligns itself with the magnetic lines of force. Other factors, of
local and solar origin, further complicate the resulting field. It may be
all right to say that a compass needle points to magnetic north, but it only
roughly points to the north magnetic dipole.
The following graphic depicts the Magnetic Declination variation as
calculated by IGRF95. Mercator projection. IAGA Division V,
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Working Group 8, International Geomagnetic Field, 1995 Revision, J.
Geomag, Geoelectr.,47,1257-1261, 1995:
Geomagnetic Main Field Models
A geomagnetic main field model is a set of a few hundred numbers
determined by 3D curve fitting a large number of geomagnetic field
observations from sites around the world. Predictive geomagnetic
models can be used worldwide, and only predict the values of that
portion of the field originating in the deep outer core.
Different geomagnetic models are available, some of which are used
within COMPASS:
� World Magnetic Model (WMM): updated every five years. Public
model available from the US Department of Defense, who provide
it on behalf of the US National Geophysical Data Center. Available
from the Internet at
http://ftp.ngdc.noaa.gov/seg/potfld/DoDWMM.shtml.
� International Geomagnetic Reference Field (IGRF): public model
updated every five years. Available from the International
Association of Geomagnetism and Aeronomy on their Internet site
at http://ftp.ngdc.noaa.gov/IAGA/wg8/igrf2000.html.
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� Definitive Geomagnetic Reference Field (DGRF): model describes
how the field actually behaved. This is also provided for five-year
intervals, and is also available from the International Association of
Geomagnetism and Aeronomy.
� British Geological Survey Geomagnetic Model (BGGM): The BGS
annually computes a model of the geomagnetic field, meeting the
demands of accuracy and Quality Assurance required for
directional drilling and well placement. The BGGM is supported by
major oil companies, service companies in the oil sector, and by the
Health and Safety Executive.The model is updated every year, and
is therefore considered more accurate. It is a commercial model,
and is therefore not shipped automatically with COMPASS. Clients
must provide proof of a license from the BGS before Landmark
will ship geomagnetic model files for use with BGGM. Information
is available from the BGS on the Internet at
http://192.171.143.111/bggm.html.
Factors that Influence Declination
The following factors influence declination and therefore magnetic
survey instruments. Their effects are noted in parentheses:
� Location (one to thousands of kilometers/degree)
� Local magnetic anomalies (0-90 degrees; 3-4 degrees frequently)
� Altitude (negligible to 2 degrees)
� Secular change (2-25 years/degree)
� Diurnal change (negligible to 9 degrees)
� Solar magnetic activity (negligible to extreme)
Location has an obvious effect, as magnetic declination varies over the
entire globe. Each position on the Earth has a particular declination. The
change in its value as you travel is a complex function. If you travel
along a straight line of equal declination, called an isogonic line, it
varies little over thousands of kilometers. However, if you cross
isogonic lines at high latitudes, or near magnetic anomalies, the
declination can change more than one degree per kilometer.
Local anomalies originating in the upper mantle, crust, or surface,
distort the WMM or IGRF predictions. Geologic features include the
following:
� ferromagnetic ore deposits
� volcanic structures, such as dikes and lava beds
� topographical features such as ridges, trenches, seamounts, and
mountains
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� ground that was hit by lightning and possibly harboring fulgurites
Cultural features include the following:
� power lines, pipes, rails, and buildings
� personal items, such as a steel watch or belt buckle, which can
cause an error of three to four degrees
In some places the field is completely vertical and a compass will
attempt to point straight up or down (for example, at the magnetic
dipoles), but there are other locations where extreme anomalies create
the same effect. Around such a place, the needle on a standard compass
drags so badly on the top or the bottom of the capsule that it cannot be
steadied.
The effect of altitude is normally negligible. According to the IGRF, a
20,000 meter climb even at a magnetically precarious location as
Resolute, NWT, Canada (500 kilometers from the north magnetic pole),
results in a two-degree reduction in declination.
Secular change is the movement of the magnetic north pole itself. As
convection currents churn in apparent chaos in the Earth's core, all
magnetic values change erratically over the years. The north magnetic
pole has wandered over 1000 kilometers since Sir John Ross first
reached it in 1831. Its rate of displacement has been accelerating in
recent years and is currently moving about 24 kilometers per year. That
is several times faster than the average of six kilometers per year since
1831.
The stream of ionized particles and electrons emanating from the Sun,
known as solar wind, distorts the Earths’ magnetic field. As the Earth
rotates, any location is subject alternately to the lee side, then the
windward side of this stream of charged particles. This has the effect of
moving the magnetic poles around an ellipse several tens of kilometers
in diameter, even during periods of steady solar wind without gusts.
The resulting diurnal change in declination is negligible at tropical and
temperate latitudes. For example, Ottawa is subject to plus or minus 0.1
degree of distortion. However; in Resolute, NWT, Canada, the diurnal
change cycles through at least plus or minus nine degrees of declination
error. This error can conceivably be corrected, but both the time of day
and the date have to be considered, as this effect also varies with
seasons.
The solar wind varies throughout an 11-year sunspot cycle, which itself
varies from one cycle to the next. In periods of high solar magnetic
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376 COMPASS Training Manual Landmark
activity, bursts of X-rays and charged particles are projected chaotically
into space, which creates gusts of solar wind. These magnetic storms
interfere with radio and electric services, and produce dazzling auroras.
The varied colors are caused by oxygen and nitrogen being ionised, and
then recapturing electrons at altitudes ranging from 100 to 1000
kilometers. The term geomagnetic storm refers to the effect of a solar
magnetic storm on the Earth.
For wellbore magnetic survey instruments other conditions that can
affect the measurement of wellbore azimuth are:
� Nearby casing, for example at KOPs
� Drillstring magnetization
� Nearby offset, P&A’d or junked wells
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True, Grid, and Magnetic North
True north
Imagine a line from you to the North Pole. This is a line of constant
longitude and points to true north. In many cases, True North is chosen
because directional survey instruments read azimuth to true (or
magnetic) north. In both cases the convergence correction does not need
to be applied. True North is an accepted reference for local co-ordinates.
Grid north
On a map, a line joining two points with equal Easting co-ordinates
points to grid north. By representing the spherical earth on a flat map,
the distortion introduced means that (over most of the map) grid north
does not point to true north. The difference between grid north and true
north is called the grid convergence. Grid north is an accepted reference
for local co-ordinates.
Magnetic North
Additionally, Magnetic north is a North reference, but is not used in
COMPASS. A magnetic compass points to the horizontal component of
the earth's magnetic field and is measured from true north. Magnetic
north varies with location and time. Magnetic North is not an accepted
convention for local co-ordinates. When loading azimuths and local co-
ordinates into Compass they should already be corrected to True or Grid
North depending on the convention chosen in the Project Properties.
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The following graphic depicts Norths’ Reference custom in Northern
and Southern Hemispheres:
In COMPASS, the convention for displaying convergence in the
northern hemisphere is that positive values are to the East (right) of True
North, negative values are to the West (left) of True North. South of the
equator, this convention is reversed.
NOTE: Diagrams are schematic.
These diagrams are schematic. The direction and magnitude of magnetic
declination and grid convergence depends upon the location.
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The following diagram depicts conventions for the sign of grid
convergence in northern and southern hemispheres, and west/east of the
geodetic zone’s central meridian.
Central
Meridian
Equator
500,000 m
G T GT
GT G T
Grid = True - Conv
Grid = True - Conv
Grid = True - Conv
Grid = True - Conv
+
+
-
-
Compass - Sign of Grid Convergence
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Drillers Target Algorithm
The following explanation describes the statistical algorithms employed
to construct a driller’s target from a geological target using the
positional uncertainty surface calculated for the wellpath down to the
TVD of the target.
Surveys show that a wellpath has penetrated a target at position.
Uncertainty at this position is represented by an error ellipse (this one
drawn at 2 standard deviations).
Points are 100 possible repeat survey locations of the actual point of
penetration in the target. The eight points lying outside the target
represent the 8% probability that the target has been missed. From this,
the inclusion probability of hitting the geological target at the calculated
point is 92%.
Geological
Target
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We can calculate the inclusion probability at every point within the
geological target and color-code it as follows:
The following graphic depicts the Plan View and 3D view (inset),
displaying a reduced size Driller’s target constructed from a circular
Geologic Target using the displayed Error Ellipse dimensions down an
example wellpath. The drillers target was constructed using a 75%
confidence level:
Well
Direction
< 90%
90-95%
> 95%
Drillers Target
defined from 90%
confidence contour
Drillers Target
Geological Target
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Select the confidence for hitting the target. The confidence is the
percentage probability that if the wellpath, when surveyed, intercepts
the target at this point, that it really is within the boundaries of the target.
A useful range is from 80% to 95%. Neither 0% nor 100% is possible.
The drilling target boundary represents a contour of confidence—points
within the boundary represent better than the required confidence.
Because the Driller’s Target tool uses the errors on the current definitive
path at the depth of the target, if the path does not go to this depth or no
errors exist, an error message appears. Additionally, to construct a
driller’s target, the tool needs a geological target that is big enough to fit
the errors, otherwise an error message appears saying the target isn’t big
enough. In this situation, you have two options: use a bigger geological
target, or assume a more accurate (and possibly more expensive!) survey
program to make the errors smaller. The driller’s target is given the
name of the original target, with the confidence label displayed.
Note: Drillers targets in live views...
In the live views, it is possible to only display drillers targets and hide geological
targets. Look in the Options tab in Graph Setup.
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Chapter
References
Brooks, A.G. and Wilson, H., An Improved Method for Computing
Wellbore Position Uncertainty and its Application to Collision and
EUROPEC, Milan, 22-24 Oct. 1996.
DuBrule, O. and Nelson, P.H., Evaluation of Directional Survey
Errors at Prudhoe Bay. SPE 15462, 1986 ACTE, New Orleans, Oct
5-8.
Harvey, R.P., Walstrom, J.E. and Eddy, H.D., A Mathematical
Analysis of Errors in Directional Survey Calculations, SPE 3718,
JPT, pp. 1368-1374, Nov. 1971.
McClendon, R.T. and Anders, E.O., Directional Drilling Using the
Catenary Method, SPE/IADC 13478, 1985 SPE/IADC Drilling
Conference, New Orleans, Mar 6-8.
Thorogood, J.L., Instrument Performance Models and their
Application to Directional Survey Operations, SPE 18051, 1988
ATCE, Houston, Oct 2-5.
Thorogood, J.L. and Sawaryn, S.J. The Travelling Cylinder
Diagram: A Practical Tool for Collision Avoidance, SPE 19989,
SPEDE pp. 31-36, Mar 1991.
Walstrom, J.E., Brown, A.A. and Harvey, R.P., An Analysis of
Uncertainty in Directional Surveying, JPT, pp. 515-523, April
1969.
Walstrom, J.E., Harvey R.P. and Eddy, H.D., A Comparison of
Various Directional Survey Models and an Approach to Model
Error Analysis, SPE 3379, SPE 46th Annual Meeting, New
Orleans, Oct 3-6, 1971.
Williamson, H.S., Accuracy Prediction for Directional MWD, SPE
56702, 1999 ACTE, Houston, Oct. 3-6.
Wolff, C.J.M. and deWardt, J.P., Borehole Positional Uncertainty -
Analysis of Measuring Methods and Derivation of Systematic
Error Model, JPT pp.2339-2350, Dec. 1981.
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