modpak exi learning modpak t version 8pages.geo.wvu.edu/~wilson/geol554/modpak.pdf ·...

December 2007

Seismic Micro-Technology, Inc.

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ModPAK

Learning ModPAK

Version 8.2

Trademarks and CopyrightThis manual was produced by Seismic Micro-Technology, Inc.

Version 8.2

December 2007

Seismic Micro-Technology, Inc.8584 Katy Freeway, Suite 400

Houston, Texas 77024U.S.A.

Tel: (713) 464-6188Fax: (713) 464-6440

Internet Address: www.seismicmicro.comE-Mail Address: [email protected]

Marketing: [email protected] Support: [email protected]

The following trademarks appear in this manual.

The KINGDOM™ software and all of its components, 2dPAK®, 3dPAK®, 2d/3dPAK®, AVOPAK®, CGMPAK®, EarthPAK®, LoadPAK®, LogPAK®, ModPAK®, PAKnotes®, OpenKINGDOM Domain®, OpenKINGDOM Scout® SynPAK®, The KINGDOM Company®, TracePAK®, Tunnel L+®, Tunnel O®, VelPAK®, VuPAK®, are registered trademarks of Seismic Micro-Technology, Inc. (SMT).

Certain software programs incorporated in KINGDOM are proprietary products copyrighted © 1993 – 2007 by Seismic Micro-Technology, Inc. All rights reserved.

Portions of data loading are copyrighted by Blue Marble Geographics.

VuPAK and VelPAK include OpenInventor™ and VolumeViz™ from Mercury Computer Systems Incorporated. Some components or processes may be licensed under U.S. Patent Number 6,765,570.

ModPAK includes SHAPES® from XOX Corporation.

Tunnel L+ includes OpenWorks® and SeisWorks® Development Kit from the Landmark Graphics Corporation.

Tunnel O includes OpenSpirit® FrameWork from the OpenSpirit Corporation.

Portions of KINGDOM bitmap graphics are based on GD library by Boutell.Com, Inc. Further information about the company can be found at www.boutell.com.

PAKnotes TIFF support is based in part on libtiff.

Rock Solid Attributes™ is a trademark of RDSP I, L.P. Solid Attributes™ contains confidential, proprietary, and trade secret information of RDSP I, L.P. This unpublished work by RDSP I, L.P. is protected by the laws of the United States and other countries. Additionally, if publication occurs, the following notice shall apply: Copyright ©RDSP I, L.P., All Rights reserved.

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Microsoft is a registered trademark of Microsoft Corporation. Windows 2000, XP, and XP x64 operating systems, MS-DOS and SQL Server are trademarks of Microsoft Corporation. Oracle® Databases are registered trademarks of Oracle Corporation. OpenWorks, SeisWorks, Interpret 2000 and Interpret 2003 are registered trademarks of Landmark Graphics Corporation.

SMT incorporates BMC® AppSight™ Black Box Technology in its software. BMC Software, BMC Software logos and all other BMC Software product and service names are registered trademarks or trademarks of BMC Software Inc. © 2007 BMC Software, Inc. All rights reserved.

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©2007 Seismic Micro-Technology, Inc. All Rights Reserved Worldwide

KINGDOM and this manual are both copyrighted and intended for use by a single user or a single computer whose model is authorized by Seismic Micro-Technology, Inc. You are entitled to electronically transcribe KINGDOM DVD to the hard disk of an authorized computer so long as KINGDOM and related software packages are operated on only one computer at a time. You are further entitled to electronically transcribe the DVD to other DVD(s) for archival storage only. Physical duplication of the KINGDOM software and SENTINEL is expressly forbidden. No portion of KINGDOM software may be incorporated into any other program. No other usage or transcription in any form is allowed without the express written permission of Seismic Micro-Technology, Inc.

No portion of this manual may be reproduced, transmitted, transcribed or stored on any information retrieval system, or translated into any foreign language or any computer language in any form and by any means whatsoever without the express written permission of Seismic Micro-Technology, Inc.This document contains confidential information and trade secrets proprietary to Seismic Micro-Technology, Inc.

Misuse DisclaimerSeismic Micro-Technology, Inc. makes no representation or warranties of any kind with respect to this manual or the KINGDOM software. Specifically, Seismic Micro-Technology, Inc. disclaims any implied or any other claimed warranties of merchantability or suitability for any particular purpose. Seismic Micro-Technology, Inc. reserves the right to modify the KINGDOM software and any of the associated user documentation at any time.

AcknowledgmentsSeismic Micro-Technology, Inc. wishes to gratefully acknowledge the contributions of the many client software testers in preparing the KINGDOM software. The enthusiastic Beta testers, smoke testers, and SMT staff greatly appreciate their invaluable feedback and contributions.

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ModPAK

Introduction

ModPAK is a 2D/3D-modeling software application designed to create synthetic seismic traces from depth models. Models can be built from little or no external data, taking what is known and applying it to what is unknown. Depth models can be derived from existing sources, such as depth grids (time grids or gridded horizons that have been converted to depth in 2d/3dPAK), well data (Formation Tops), imported depth grids, fault cut data and hand digitized data. Models can also be created from templates provided by SMT.

The model is constructed using depth surfaces (horizons and faults). These surfaces delineate layers. One or more blocks are assigned to a layer. Layers contain lithology types and patterns as well as the selected property extrapolation methods. Physical properties such as velocity and density are identified for a block. These physical properties are derived in the model at user defined locations which are typically well locations. The physical properties are extracted from well logs or can be entered manually using the keyboard. Physical properties are interpolated through the model using one of three extrapolation methods illustrated in Figure 1.

• Stretch/Squeeze from top to bottom will interpolate properties by linearly stretching or squeezing the well log data between two wells as the horizons either expand or contract between the wells.

• Conformable to Upper Surface will interpolate properties between wells and assume the properties to be conformable to the upper surface. If the section expands to a thickness greater than the interpolated properties’ thickness, the value at the base of the interpolated data will be extrapolated to fill the expanded lower section. This method results in an On Lap geometry – the top values conform to (follow) the UPPER surface.

• Conformable to Lower Surface will interpolate properties between wells, and then assume the properties to be conformable to the Lower Surface. If the section expands to a thickness greater than the interpolated properties’ thickness, the value at the top of the interpolated data will be extrapolated to fill the expanded upper section. The method results in an Off Lap geometry – the top values conform to or follow the LOWER surface.

After the model is constructed, that is, all surfaces and layers are identified, all blocks are assigned material properties and subsequently assigned to layers, then synthetic seismic traces can be generated over the model.

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Figure 1 Property Extrapolation Methods

Example - Stretch/Squeeze

Example - Conformable to Upper surface

Example - Conformable to Lower Surface

2 KINGDOM 8.2

Model Creation Workflow

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Model Creation Workflow

Identify Geological / Geophysical Problem

Use saved arb line to place wells in modelModel Manager Create Model Name

Add InterpretationDepth Grids / HorizonsFormation TopsFault Cuts

Model Layers

Assign Blocks to Assign material property values (constant or from

Generate Model

Select the extrapolation method for the Layer

Create Layers

to the Blocks

Select a log Log conversion option

Layers

Compute Property Distribution

TracesCompare synthetic traces withactual seismic traces

log)

KINGDOM 8.2 3

Modeling Guidelines and Considerations

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Experienced modelers know that it is often wise to model only to the extent necessary to answer their question(s). It is important to think through your model before beginning it. The sign of an inexperienced modeler is an overbuilt model. Overbuilding not only wastes times, but also leads to the inclusion of inferior quality data. Keep it as simple as you can. Quite often, an extremely simple model can answer your particular question.

Be sure to think through your model before beginning it. Ask yourself what you expect to accomplish through modeling. What results do you anticipate? What is the best approach to test your hypothesis?

Modeling is often an iterative process. Model surfaces or physical parameters are adjusted frequently and the results compared. Remember, change only a limited number (1 is best!) of items in each iteration. Although it is easy to make several parameter value changes at once, the results are ambiguous. Without using a controlled variable you cannot be sure of the effects of a single parameter.

Only one set of traces can be saved with a single model. In a future release when other trace types, including Image Ray, CMP, and Common Shot become available, a single set of each type of resultant traces can be saved.

Any alteration of your model invalidates the derived synthetic traces. We currently do not have any mechanism to warn you of this. It is up to you to remember that any horizon, surface, or material property change will produce different synthetic trace results.

To retain synthetic traces of various model iterations, you need to make a copy of the model first. After the model has been copied make the desired edits and changes, and then regenerate the traces.

Modeling results provide only plausible answers. It should not, despite what other modeling companies say, be used to “verify” your interpretations (only drilling can do that!). Remember that varying input data for two or more data types can produce somewhat similar results.

Most models do not use much disk space, so it is wise to save them. However, resultant synthetic traces can use a lot of disk space. If you find you are getting low on space, you can delete the synthetic traces and regenerate them easily later on.

Always make backups of your models.

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ModPAK Terminology:

Table 1

Point An individual point with an X, Y, and Z value.

Segment A segment is two or more points connected by a line. One or more segments compose a “Model Surface.” Segments are either Assigned or Unassigned. “Assigned” means the segment is part of some named Surface.

Surface Comprised of one or more segments. In ModPAK there are three types of Model Surfaces: Horizon, Fault and Lens.

Block An enclosed area (polygon) bounded by Surfaces and/or model boundaries. Material Properties are assigned to blocks using log data or constant values.

Layer A group of similar (geological) blocks. For example, all the blocks bounded by Horizon A, Horizon B, several faults, and the left and right model bound-aries. A layer is characterized by a specific lithology pattern and material property extrapolation method.

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Basic ModPAK Workflow

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The objective of this exercise is to familiarize you with the basic ModPAK workflow, terminology and functionality used in constructing a forward seismic model. You will build a simple model across the Sooner Field, which is located in Weld County, northeastern Colorado. The reservoir is interpreted to be a funnel-mouth estuary, opening from the north and expanding to the southern end of the field. Production is from the Cretaceous D Sand at about 1.40 seconds. You will compare the resulting modeled traces with the actual seismic data.

1. Open the sooner3d.tks project and select Demo in the Select Author window.

2. Create a 2d well subset following the steps below:

a. From the active Base Map choose Wells > Select Wells to Display > By List or Polygon.

b. Click on the None button to unhighlight wells in the well list.

c. From the List tab select the following wells by holding down the <Ctrl> key and MB1.

FEDERAL SOONER 7-21

SOONER UNIT 5-21

SOONER UNIT 6-21

SOONER UNIT 9-21

d. Save the well list as a subset by clicking the Save As Subset button.

e. Name the list, Sooner Model Wells.

f. Click OK.

g. Close the Select Wells to Display dialog box.

3. On the Base Map, digitize an arbitrary line through the wells by right-clicking and selecting Digitize Arbitrary Line > Single Line with Selected Wells.

a. The Digitize Arbitrary Line with Selected Wells window appears.

b. In step 1, digitize the line as shown in Figure 2.

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c. In step 2, after you click on the wells, the selection(s) will turn a teal blue color where the projected well intersects the arbitrary line.

Figure 2 Example of Single Line with Selected Wells

d. The Arbitrary Line A window will appear. You may need to turn off the formation tops by unchecking the box next to Formation Tops in the active Tree. The logs displays will be discussed below.

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Figure 3 Vertical seismic display

e. In the vertical seismic window, select the Set Scales icon.

f. Set the Vertical scale to 30 Inches per Second and the Horizontal scale to 10 Traces per inch.

g. Click OK.

4. Save the arbitrary line by choosing from the main menu, Line > Arbitrary Line > Save As. Name the arbitrary line, Sooner A-A.

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Display Log CurvesDisplay the GR and LLD curves along the borehole paths on the arbitrary line:

1. On the vertical seismic display, click the Log Settings icon.

a. On the Scale and Style Setup tab, in the Category field, select Digital Logs.

b. Place the GR curve into Track 1 by selecting GR then click on Track 1 and click the right arrow button. The curve will appear in the Displayed Curves area.

c. In the Line section, select the Spring Green color from the Color drop-down menu (the name will appear in the field), click Apply.

d. Place the LLD curve in Track 2, assign a Red Line Color and check Logarithm scale. Click Apply.

a. On the Define Curve Tracks tab uncheck the check boxes for Depth Track, Track 1 and Track 2.

a. Click OK. Your display should resemble Figure 3.

Create the Model1. Launch ModPAK by choosing Project > ModPAK from the main menu bar.

a. Click Yes to the warning message: Every cross-section must be displayed in the context of a 3D model. No models have been created in this project. Would you like to create a new model?

b. The Model Management dialog box appears. On the Create tab enter Sooner Model as the New Model Name.

c. For the Vertical Bounds toggle ON Subsea for the Depth Type.

d. Enter a Starting Depth of -1200 feet and an Ending Depth of -2000 feet.

e. Click OK.

2. The Select Map Coordinates dialog box appears.

3. Toggle ON Arbitrary Line, select Sooner A-A.

4. Click OK.

The ModPAK workspace opens and displays the arbitrary line.

5. In the workspace do the following:

a. Select Wells > Borehole Display Options and enter 1000 feet into the Borehole Projections window.

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Click OK.

If any of your wells are not displayed on the ModPAK workspace the well may fall outside the projection envelope around the line.

b. Adjust the scales with the Set Scales icon . Set the Horizontal scale to 500 Feet Per Inch and the Vertical scale to 100 Feet Per Inch. Toggle ON Subsea.

c. Accept the other defaults and click OK.

Add Depth InterpretationThere are three types of depth data you can add to the model: Depth Grids, Formation Tops and Fault Cuts.

Note: In order to be visible in the ModPAK model, horizon time grids, horizon and fault time interpretations must first be depth converted.

1. Make the ModPAK window active and choose Models > Add Interpretation.

a. In the Add Interpretation wizard, deselect Depth Grids and Fault Cuts leaving the Formation Tops option selected, click Next.

b. In the Select Formation Tops window, click All for Wells as shown in Figure 4.

c. In the Tops list pane, hold down the <Ctrl> key and click MB1 on the following tops: D Sand and J Silt.

d. Click Finish.

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Figure 4 Select Wells and Tops

e. ModPAK interpolates and extrapolates the formation tops in the selected wells to construct horizon depth surfaces.

f. Observe the layers by moving your cursor into the workspace and clicking MB1. The selected layer will be highlighted with diagonal hatching.

An Example of hatching is shown in Figure 5.

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Figure 5 Example of Layer Hatching

Create Model LayersThe model blocks contain velocity and density values. These values can be taken from electric logs or entered manually after the blocks are assigned to a layer.

The layer contains lithology pattern, color and the extrapolation method used to distribute velocity and density values between wells for the model layer/block assignment.

Extrapolate describes the way velocity and density or other material properties will be interpolated and extrapolated throughout the model layer/blocks. There are three extrapolation options:

• Stretch/Squeeze — The material properties are stretched and squeezed vertically to follow the bounding layers.

• Conformable to Upper Surface — The material properties will remain the same along the upper bounding surface but will be extrapolated downward for layers which vary in thickness.

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• Conformable to Lower Surface — The material properties are held constant along the bottom layer and are expanded upward for layers which vary in thickness.

1. Make ModPAK the active window and choose Models > Layer Management to open the dialog box shown in Figure 6.

Figure 6 Layer Management dialog box

a. On the Create tab use the information provided in Table 1 to enter the following.

a. Click Apply after each entry.

b. When finished click Cancel.

Table 1 Layer Characteristics

Layer Name Extrapolation Method Fill Color Lithology

Upper Stretch/Squeeze Light Salmon Shaly Sand

D Sand Stretch/Squeeze Yellow Sand

J Silt Conformable to Upper Surface

Brown Shaly Sand

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Assign Model Blocks to LayersNow that the model layers have been created with the desired extrapolation method, fill color and lithology, you will assign the model blocks that were constructed earlier to the layers that you just created. The velocity and density determination method will also be selected at this time.

Assign Upper Block to Upper Layer

1. Activate the ModPAK window and select Models > Assign or Unassign Layers to Blocks to open the dialog box shown in Figure 7.

Figure 7 Assign / Unassign Blocks dialog box

a. Step 1- In the ModPAK workspace, click the upper block with MB1 to select it which will be hatched in the workspace.

b. Step 2 - In the Assign or Unassign selected blocks area, click the down arrow and select the Upper layer.

c. Click the Assign to Layer! button. The layer characteristics assigned to that block will display in the ModPAK workspace as shown in Figure 8.

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Figure 8 Example showing Block 1 being assigned to Upper Layer

d. Click the Block(s) Properties button (Figure 9).

Figure 9 Block Properties dialog box

Choose the property assignment input. The default is to use logs. This will determine the velocity and density log values to be distributed across the Block. In the absence of logs you can enter appropriate velocity and density constant values as a substitution.

e. Click OK.

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Assign Middle Block to D Sand Layer

1. In the ModPAK workspace, click the middle block with MB1 to select it which will be hatched in the workspace.

2. In the Assign or Unassign selected blocks dialog box, click the down arrow and select the D Sand layer.

3. Click the Assign to Layer! button. The layer characteristics assigned to that block will display in the ModPAK workspace.

Assign Lower Block to J Silt Layer

1. In the ModPAK workspace, click the lower block with MB1 to select it which will be hatched in the workspace.

2. In the Assign or Unassign selected blocks dialog box, click the down arrow and select the J Silt layer.

3. Click the Assign to Layer! button. The layer characteristics assigned to that block will display in the ModPAK workspace.

4. When finished, close the Assign/Unassign Blocks dialog box. Your model should resemble Figure 10.

Figure 10 Example of blocks assigned to layers

Block0

Block0

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Compute Property DistributionThe next step in the process is to compute the property distribution through the model. The Compute Property Distribution dialog box allows the user to distribute the properties of selected logs within a model. Use this option to check the property distribution before generating synthetic traces.

Compute Property Distribution extrapolates the density and velocity property values throughout the various blocks. A graphical display of the extrapolation can be used to quality check the material distribution before generating the synthetic or modeled traces.

For models based on cross sections, use Trace Spacing to compute how often the properties will be computed horizontally. In our case the model is based on a 3D survey so the trace spacing will corresponding to that of the Sooner3D survey which has a 100 foot by 100 foot bin size.

1. Choose Models > Distribute Properties to open the Compute Property Distribution dialog box shown in Figure 11.

Figure 11 Distribute Properties interface when Yes or No is selected

2. There is no velocity curve. Therefore, we will create one by converting the LLD curve to a velocity curve using the Faust equation.

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a. In the Compute Property Distribution dialog box, toggle ON Yes and select the LLD log curve.

b. Check the Apply Log Conversion option.

c. Toggle ON Convert to Velocity.

d. Accept the default for Trace Spacing.

The trace spacing is based upon survey bin size.

e. Enter a Sample Interval (traces) value of 1.0.

f. Click Apply.

To learn more about the other available options, refer to Table 2 below, Compute Property Distribution Options.

g. Click Cancel to close the window.

3. Display the Color Bar in the ModPAK workspace by clicking on the Show Color Bar icon

.

4. Click the select icon and choose the Rainbow 200.CLB as the color map.

5. Adjust the model’s vertical scale and color map to better view the distributed properties as shown in Figure 12.

Table 2 Compute Property Distribution Options

Option Description

Trace Spacing Determines how often the properties will be computed horizontally. (Feet or Meters)

Sample Interval (traces) Determines how often the properties will be computed vertically. (Feet or Meters)

Type of Plot Display options include High Resolution, Low-Resolution, Wiggle Trace and Wiggle Variable Area

Auto Update Property Distribution Whenever the Model is Updated

Turn this option OFF if you want to do a number of edits

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Figure 12 Computed Properties example

6. Examine the display. Changes can be made to the various blocks at this time and the property distribution recalculated to reflect the edits.

Compute Seismic Traces1. After examining the property distribution display, compute the synthetic traces by choosing

Models > Compute Seismic Traces. This opens the multi-tabbed Compute Seismic Traces dialog box shown in Figure 13.

Block2

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Figure 13 Compute Seismic Traces dialog box

2. On the Traces tab, enter a Trace Start Time of 0 seconds and a Trace End Time of 1.5 seconds.

3. On the Velocity tab, choose the LLD log curve. The conversion from resistivity to velocity will be made using the Faust equation.

4. On the Density tab, uncheck Use Constant Density and select the RHOB log.

5. And finally, on the Wavelet tab, select the default Ormsby wavelet.

6. Click OK.

7. The Arbitrary Line A vertical window will open with a Hi Res Color Raster display as shown in Figure 14.

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Figure 14 Example of Sooner Model computed seismic traces

8. Change to color map to Red to White to Blue 200.CLB

9. In the Arbitrary Line A window, click the Wiggle Overlay icon .

a. From the Wiggle Overlay window that opens set the Data Type to *Amplitudes (Time), and the Overlay Trace Increment to 2 or 3.

b. Toggle ON Wiggle Variable Area and Trough Fill.

c. Click the Wiggle Options button and for Trough Fill Color select LightSpringGreen.

d. Click OK.

e. Adjust the display gain of the wiggle overlay by clicking <Ctrl> + <F5> or <F6> as needed.

f. Click OK to dismiss the Wiggle Overlay dialog box.

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Figure 15 Model Seismic Traces (Hi Res) with Actual Seismic Traces (Trace Overlay)

10. Close ModPAK and the SOONER project.

22 KINGDOM 8.2

Modeling a Stratigraphic Lens

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This exercise is purely hypothetical and is designed to demonstrate how to model a stratigraphic lens.

1. In the KINGDOM Software Version 8.2 Start Page, open the BEG demo project.

2. Select Project > New Vertical Display.

3. On the Select Line from Wells tab toggle ON Select Wells.

4. Choose the Straton #17, #13 adn #10 wells and click OK.

5. Save the Arbitrary line by selecting Line > Arbitrary Line > Save As. Enter the name, Model A.

6. Click OK.

Build a Log Template

1. Build a log template by clicking on the Log Settings icon .

2. On the Scale and Style Setup tab, place the GR log onto Track 1. Choose your color and click OK.

3. Adjust the Cross Section Vertical scale to 200 feet per inch and Horizontal scale to a Fixed Distance between Track Edges to 2 inches. Hint; Click the Set Scales icon .

4. Select Project > ModPAK.

5. Answer Yes to the pop-up message.

Create Model1. In the Model Management dialog box and on the Create tab enter the name, Model A.

a. Toggle ON Subsea.

b. Set the Starting Depth to -6000 feet and Ending Depth to -8000 feet.

c. Click OK.

2. In the Select Map Coordinates dialog box, click the down arrow and select Model A.

3. Toggle ON Arbitrary Line and choose Model A.

d. Click OK.

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4. Readjust the ModPAK scales by clicking on the Set Scale icon .

5. Enter a Vertical scale of 200 feet per inch and a Horizontal scale of 700 feet per inch.

Select Models > Add Interpretation (Figure 16).

Figure 16 Add Interpretation dialog box

Check ON Formation Tops only.

Click Next.

Click the All button to select all the wells.

This is will display a list of tops. Highlight the F21, f37 and f39 tops and click Finish (Figure 17).

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Figure 17 Three tops added to the Model

Model Lens

1. In the Surfaces toolbar click the down arrow and select Unassigned Lens.

a. Click the Digitize Surface icon and digitize the sandstone lens shown in Figure 18.

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Figure 18 Unassigned Lens

2. Create a new layer in the Layer Management dialog box by clicking the Layer Manager icon and navigating to the Create tab.

3. In the New Layer Name text field enter Lens A.

a. Select the Stretch/Squeeze extrapolation method.

b. Set the Fill Color to Yellow and the Lithology to Sand.

c. Click OK.

4. In the ModPAK workspace click the lens to select it. The lens will display hatchures.

5. In the Layer toolbar, , select Lens A and click the Assign

Block icon .

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Create and Assign Layers to the Other Blocks1. In the ModPAK workspace, click on the upper layer. It will appear hatched.

2. Click on the Layer Manager icon .

3. Using the table below create layer names, select an extrapolation method, fill color and lithology pattern.

4. Click OK after each layer to create a layer then reopen the Layer Manager for the next layer.

5. Once the Layers and layer properties are created you need to assign the layers to the Model Blocks.

6. In the ModPAK workspace click on the upper layer which will become hatched when selected.

7. In the Layer Tool Bar , click the down arrow and

choose the Upper Layer.

8. Click the Assign Block icon .

The Upper Layer is assigned to Block 1.

9. Now perform the assignments for the other layers. When finished your ModPAK workspace should reassemble Figure 19.

Table 1 Assign Layer to Blocks

Block Layer Extrapolate Fill Color Lithology

Block 0 Lens A Stretch/Squeeze Yellow Sand

Block 1 Upper Layer Stretch/Squeeze Brown Shale

Block 2 F37 Layer Stretch/Squeeze Tomato Sandy Shale

Block 3 F39 Layer Stretch/Squeeze MediumGray Shale

Block 4 Lower Layer Stretch/Squeeze Wheat Sandy Shale

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Figure 19 Model A with Lens and Lithology Display

Compute Property Distributions

1. Open the Compute Property Distributions dialog box with this icon , and toggle ON Yes to Distribute Properties.

a. Highlight RHOB in the Select a log window.

b. Click Apply and after the computation has finished, click Cancel.

Compute Seismic Traces

1. Open the Compute Seismic Traces .

2. Accept the default parameters for the Traces tab.

3. On the Velocity tab, use RHOB.

4. On the Density tab use RHOB.

5. Choose the Ormsby wavelet on the Wavelet tab.

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6. Click OK. Figure 20 is showing the results of the synthetic traces over the hypothetical sand lens on the Stratton #13 well.

7. Select the Set Scales icon and toggle ON Wiggle Variable Area with a Peak Fill.

8. Adjust the gain of the seismic display by using View > Seismic Amplitude Scale options.

Figure 20 Wiggle Display of modeled lens

You have successfully modeled a hypothetical lens.

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