0806514_hydro log book

16
RESEARCH AND APPLICATIONS IN HYDROGRAPHIC SURVEYING EXTERNAL SPEAKER LOG BOOK Wednesday 22 nd April 2015 0806514 EXECUTIVE SUMMARY This log book contains summaries from talks by speakers from the Hydrographic Surveying profession and four summaries from sessions at Hydro-fest 2015. This includes talks from iSurvey, Shell, Subsea 7, DeepOcean, Nautronix, Veripos, Fugro, Harkand Andrews and Bibby Offshore. 0806514 of 1 16 Hydrographic Surveying

Upload: peter-mccready

Post on 16-Aug-2015

80 views

Category:

Documents


0 download

TRANSCRIPT

Page 1: 0806514_Hydro Log Book

!RESEARCH AND APPLICATIONS IN!

HYDROGRAPHIC SURVEYING!EXTERNAL SPEAKER LOG BOOK!!!

Wednesday 22nd April 2015 0806514

!!!!!!!!!!!!!!!!!!!!!!!EXECUTIVE SUMMARY!!This log book contains summaries from talks by speakers from the Hydrographic Surveying profession and four summaries from sessions at Hydro-fest 2015. This includes talks from iSurvey, Shell, Subsea 7, DeepOcean, Nautronix, Veripos, Fugro, Harkand Andrews and Bibby Offshore.!!!

0806514� of �1 16Hydrographic Surveying

Page 2: 0806514_Hydro Log Book

iSurvey! ! ! ! ! ! ! ! ! ! 25/02/15!!The talk from iSurvey was presented by Alasdair Howe (HR coordinator) and former University of Glasgow student Steven Strathie (Operations manager). The session took place on Wednesday the 25th February 2015 on the main University of Glasgow campus, room 418.!!iSurvey are an offshore surveying company with their head office based in Oslo, Norway. They also have offices in Singapore and Aberdeen which opened for business in 2011 and 2014 respectively. The company are ISO 9001:2008 certified, are a member of the International Marine Contractors Association (IMCA) and have a joint operations agreement with the Norwegian remotely operated vehicle (ROV) specialists IKM Subsea.!!The company performs high precision rig and Floating Production Storage and Offloading (FPSO) operations including jack-up and semi-submersibles, prism installations, anchor handling (e.g. with Statoil) and establishing reference frames for relative and absolute positioning.!!iSurvey also provide marine construction support and cabling. Current customers include NEXANS Cables Worldwide, ABB Cable Division and STATNETT. The cabling is commonly used to connect offshore renewable energy sources to the national grid through subsea cabling.!!In the future iSurvey look to undertake pipe lay, pipeline metrology, heavy lifts (platforms into place etc), make Aberdeen the main office (aim of Steven Strathie and Alasdair Howe), and expand the company into other markets (e.g. Asia, Africa and Gulf of Mexico).!!iSurvey have a range of systems including:!!• iNAV - a helmsman display that provides real-time navigation with survey systems such as

USBL, LBL, surface GNSS and jack-up total station positioning.!!• iCABLE - specialised system for offshore cable installations!!• iMAP - seabed mapping projects, provides 3D DTMs, bathymetry and video!!• iROV - ROV system for survey applications!!• iSAFE - a positioning and display system for multi-vessel operations!!• iMON - rig positioning visualisation and movement calculations!!• iBUOY - transponder based anchor positioning!!• iCONTROL - remote control of offshore survey systems through secure internet connection!!!!

0806514� of �2 16Hydrographic Surveying

Page 3: 0806514_Hydro Log Book

iSURVEY Graduate Scheme:!!Looking to employ 2-4 Offshore Surveyors and 3-4 Trainee Surveyors.!!The employment process consists of 1st interviews with the HR coordinator and Operations manager (based at the University of Glasgow), 2nd interviews with the HR coordinator and HR director (based in Southampton) and a 2-3 day technical and practical assessment centre (based in the Central Belt). If successful the candidate will start work in September 2015 and undergo an induction and offshore training in Aberdeen.!!The company will put the successful candidate through the BOSIET (offshore safety and survival training), CA-EBS (emergency breathing system training), Minimum Industry Safety Training (MIST), Norwegian Escape Chute training and offshore medical. There is also a 10 day basic training course taking place in Oslo, Norway, that will train the candidate in the use of iSurvey systems - this is a theory and practical course.!!The scheme involves undergoing placements in different departments in the business (e.g. Project Management, Business Development etc). Trainees normally keep their trainee status for approximately 6 months. Career progression is aligned with IMCA competencies.!!!• There is no clearly defined work schedule (4 weeks on 4 weeks off is not regular)!• Allocations are normally provided 1-2 weeks in advance if possible but there may be last minute

call-ins.!• The company covers door-to-door expenses for work-related travel (food, accommodation and

travel costs).!• There is no relocation requirement as long as the candidate is based in Europe within 1-2 hours

of a major airport, ideally with direct flights to Aberdeen, Oslo, Pairs, Amsterdam, London or Copenhagen.!

• ONIX system, read-only version of the personnel database that provides an online version of allocation!

• The company communicates through Microsoft Outlook and Lync Messenger.!• 28 days paid holiday per year.!• Possibility to work from home if working onshore.!• Company-provided work phone, laptop, laptop bag and home internet (if working from home).

0806514� of �3 16Hydrographic Surveying

Page 4: 0806514_Hydro Log Book

Shell UK ! ! ! ! ! ! ! ! ! ! 06/03/15!!The talk from Shell UK was presented by Rhian Parkin, GeoInformation Management (GIM) Analyst at Shell UK. The session took place on Friday the 6th March 2015 on the main University of Glasgow campus, room 418. Shell have main offices in Aberdeen, Netherlands and Norway.!!The company looks after 135 offshore structures, >6000 well bores and 725 pipelines and utilities.!!The talk focussed on Rhian’s work at Shell and the role that geomatics plays in the Oil and Gas industry, upstream exploration and production in particular.!!It is estimated that reliance on oil will taper off towards 2060 with higher investment in natural gas, coal and nuclear (among other) sources of energy.!!Offshore surveying and positioning covers rig moves in particular, with approximately 80 rig moves per year using self propelled means or by tug-boat movement of the rig requires surveyors to ensure the rig is positioned correctly away from subsea infrastructure. A debris survey is required before rig positioning to map the seafloor and display any obstructions to the proposed move. This is done using single-beam, multi-beam, sidescan and bottom profilers.!!Onshore surveying and positioning involves procedures such as; setting out, dimensional control (e.g. using CAD models), as-built surveys, land and legal (e.g. demarcation) and subsidence monitoring (e.g. as oil is extracted the land above may subside to fill the gap).!!Shell also utilise remote sensing and deformation monitoring using satellite, thermal imaging and subsidence monitoring. Note: an increase in temperature usually indicates someone tapping into the pipeline to steal oil. Site selection for infrastructure lays is also performed using subsea mapping by analysing hydrographic survey data and identifying suitable areas and routes.!!Geodesy is a further branch of geomatics that is crucial to Shell’s operations. ED50 is used with Europe and WGS84 is generally used elsewhere. Incorrect application can lead to costly errors such as the following examples:!

• ! Pipeline materials were over budgeted for by 30% due to the wrong map projection !! being used.!

• ! Missing seafloor data lead to a transit barge running aground with oil platform ! !! topside cargo and capsized.!

• ! An incorrect assumed boundary lead to reputation issues, litigation and loss of ! !! privileged data.!

• ! Missing pipeline or cable data - means costly rig move delays or damaged lines.!• ! Correct latitude and longitude coordinates used within the incorrect coordinate ! !! system may lead to drilling in the wrong location (possibly hundreds of metres ! !! apart). Won’t strike oil and will require an expense rig move.!!

Shell also using mapping for incident preparedness and rapid emergency response (e.g. Shell MyMaps system that integrates global oil and gas infrastructure positioning data from DECK).!!

0806514� of �4 16Hydrographic Surveying

Page 5: 0806514_Hydro Log Book

Rhian also covered the Exploration and Production lifecycle in more detail, in particular the explore stage as geomatics plays a key role in this area.!The Exploration and Production lifecycle incorporates:!!(1) Explore (seismic support, positioning for rig moves, maps using ArcGIS and databases)!(2) Appraise (seabed surveys)!(3) Develop (pipe-lay surveys)!(4) Produce!(5) Decommission !!Exploration involves seismic support, positioning for rig moves, maps using ArcGIS and databases.!Shell split this stage into Identify, Assess and Select phases.!!• The Identify phase covers; coordinate assurance, remote sensing, seep hunter (uses satellites to

identify natural seeps and slicks on the seabed that give an indication of hydrocarbons underground), area discounting, nontechnical risks, shallow geo-hazards, maps (e.g. Shell’s MyMaps platform) and seismic acquisition. This phase is mostly about identifying the next large oil/gas reservoir.!!

• The Assess phase includes site selection, spatial data expertise and urban planning.!!• The Select phase focusses on common operation, mobile mapping and pipeline routing.!!In terms of subsea mapping Shell collates run-lines into a 3D seismic data grid known as a BIN. Seismic data is supplied by the Technical Data Management team to the GeoInformation Management team, transformations are applied, orthogonal checks are performed and the data is then distributed to the business.!!!Shell offer careers opportunities in rig and vessel positioning, construction support, inspection and seabed surveys (site/route surveys). However, they do not perform the surveying in-house. This type of work is contracted out to companies such as Deep Ocean, DOF, Fugro, Gardline, Harkand Andrews, Integrated Subsea Services, Marine Offshore Designers, MMT, NCS, iSurvey, Sonsub Saipem, Specialist Subsea Services, Subsea7 and UTEC.!!The career path of an offshore surveyor is generally:!!(1) Trainee Surveyor!(2) Surveyor!(3) Senior Surveyor!(4) Party Chief!(5) Onshore Project Manager!(6) Onshore Senior Management!!!

0806514� of �5 16Hydrographic Surveying

Page 6: 0806514_Hydro Log Book

Subsea7 ! ! ! ! ! ! ! ! ! ! 13/03/15!!The Subsea7 session was presented by Neil Muir (Life-of-field) on Friday the 13th of March 2015 on the main University of Glasgow campus, room 418.!!Neil’s talk focused on Autonomous Underwater Vehicles (AUVs) and closely examined Subsea7’s Autonomous Inspection Vehicle (AIV). In basic terms AUVs are programmable robots that can travel underwater without input from an operator.!!The main developers of AUVs include; Kongsberg, Remus, Hugin, Munin, Bluefin Robotics, Teledyne, Ocean Server and Subsea7. Main AUV markets are for defence and scientific purposes.!!Subsea7 are a company consisting of 40+ vessels, 175 Remotely Operated Vehicles (ROVs), 14,000 people and 2,000 engineers. Life-of-field operations include; survey services, inspection, ROV, Remotely Operated Towed Vehicle (ROTV) & AUV, Geomatics, Geographic Information System (GIS) and quality assurance services.!!!AUV APPLICATIONS!AUV applications include:!!• Commercial!

- ! Oil & Gas!- ! Inshore!- ! Offshore (e.g. pipeline inspection, pre-lay & post-lay surveys)!- ! Search and Salvage!

• Military!- ! Mine Hunting!- ! Submarine Detection!

• Research!- ! Sub-ice-cap monitoring!

• Hobby!!!COMMON SENSORS!Common sensors found in AUVs include but are not limited to;!!• Positioning!

- ! Differential Global Navigation Satellite System (DGNSS)!- ! Inertial Navigation System (INS)!- ! Doppler Velocity Log (DVL)!

• Sensors!- ! Single-beam Sonar!- ! Multi-beam Sonar!- ! Side-scan Sonar!- ! Sub-Bottom Profiler!

0806514� of �6 16Hydrographic Surveying

Page 7: 0806514_Hydro Log Book

- ! Video/Fast Stills Cameras!- ! Conductivity, Temperature and Density (CTD) Profiler!- ! Cathodic Protection!- ! Depth Pressure Sensor!- ! Auto-tracker (detects pipe and auto-tracks it alongside the side-scan sonar shadow,

parameters can be set during mission planning to track a particular pipe)!• Operations!

- ! Battery (commonly 4-6 hours life)!- ! Propulsion!- ! Obstacle Avoidance!- ! Altimeter!!

AUV adjustable navigation variables include; constant depth/altitude, speed (m/s), and waypoints/run-lines. All variables adopt the WGS-84 format.!!Neil also explained that an AUV can be fully modular, meaning each module can be unscrewed and fitted with another. i.e. the AUV can have a sensor removed and replaced with another.!!!TELEDYNE GAVIA!Neil used a case study of an NCS Survey project for BP in Azerbaijan, involving pipeline inspection using the Teledyne Gavia AUV. This project was a harbour and channel survey lasting 3 days.!!Successes of the project included; good data quality and acquisition, successful auto-tracking, cost was 30% of an ROV survey, survey carried out 5 times faster than with an ROV, project was nominated for the BP Helios Award.!!Challenges of the project included INS drift and data processing issues. The INS drift was remedied using a lawnmower run-line pattern, the change in direction prevented large drift occurring. Data processing software had to be changed.!!!SUBSEA7 AIV!The final part of Neil’s presentation focussed on Subsea7’s AIV for life-of-field operations. The presentation was provided by Lee Wilson, the AIV Project Manager.!!The AIV has been designed and tested by Subsea7 and incorporates SeeBytes auto-tracking tech.!!Key technology within the AIV such as hover/ stop/ close manoeuvring capability, feature-based and dead-reckoning navigation, basket launch and recovery, and subsea docking help make the AIV unique from the AUV family.!!The AIV can operate at up to 2knots speed, at 3000m depth for a maximum of 24 hours or 40km excursion, at 300m range. The AIV incorporates PAIV (hover capability), SeeByte Autotracker and SPINAV (riser tracking functionality) technology.!!

0806514� of �7 16Hydrographic Surveying

Page 8: 0806514_Hydro Log Book

Advantages of the AIV include;!!• No need for expensive vessels for deployment!• Compact systems!• Topside or subsea residency using subsea docking!• Minimal support/ crewing requirements!• Onshore/ remote control!• Potential of increased surveillance and inspection regimes!!!FUTURE OF AUVs!!• Better batteries (longer excursion duration)!• Better telemetry - increased range and bandwidth!• Additional tooling/sensors - intervention (e.g. turning valves etc)!• Subsea garage/ docking stations (e.g. don’t have to recover in rough seas)!!!DRONE APPLICATIONS!!• Helicopter/ octocopter inspections!• Fixed wing - e.g. Trimble UX5!• Used for Normally Unattended Installation (NUI) Inspections!!!!

0806514� of �8 16Hydrographic Surveying

Page 9: 0806514_Hydro Log Book

Deep Ocean! ! ! ! ! ! ! ! ! 20/03/15!!The talk from Deep Ocean was presented by Ruaraidh Martin (Graduate Surveyor), a 2014 graduate of the MSc in Geospatial & Mapping Science at the University of Glasgow. The session took place on Friday the 20th March 2015 on the main University of Glasgow campus, room 418.!!Ruaraidh’s talk focussed on Deep Ocean, their main areas of expertise, his current role and his job hunting and interview experiences. His current role is as an offline surveyor, performing data processing as the real-time data is collected. He is also currently learning about calibrations. In his team he works with 2 other offline surveyors (data processing), 2 online surveyors (data acquisition), one senior surveyor and an offshore manager.!!Deep Ocean is a Norwegian company with offices in Aberdeen, Norway, Holland, Mexico, Brazil and Singapore. It has a fleet of 17 vessels that perform ROV/Survey, Inspection Maintenance and Repair (IMR) and Construction operations. Nine of these vessels are company owned. From Ruaraidh’s experience the company’s main line of work is in ROV inspection, maintenance and repair operations.!!Ruaraidh’s graduate scheme consists of offline surveying (data processing) tasks in the first year and moving into online surveying (data acquisition) tasks in the second year.!!So far Ruaraidh has worked on the Enagas Pipeline Inspection project in the Balearics and the BP North Sea Pipeline Inspection project which he is set to continue for the rest of this year.!!The presentation was completed with a set of questions from the floor, mainly about offshore life and current job prospects for surveyors within the oil and gas industry. The presentation was very interesting and it was good to hear what offshore life is like from the perspective of someone who recently completed the course.!!

0806514� of �9 16Hydrographic Surveying

Page 10: 0806514_Hydro Log Book

Nautronix! ! ! ! ! ! ! ! ! ! 27/03/15!!The talk from Nautronix was presented by Ross Leitch (Project Surveyor). Ross previously attended the University of Glasgow to study an undergraduate degree in Topographic Science and then a postgraduate degree in Geospatial & Mapping Science. The session took place on Friday the 27th March 2015 on the main University of Glasgow campus, room 418.!!Ross worked for a land survey company prior to going offshore to work as a hydrographic surveyor and explained that the fundamentals of land survey were equally applied for operations offshore. He noted that land survey experience would be desirable for a hydrographic surveyor position.!!The presentation focussed on survey sensors and applications, mainly remotely operated vehicles (ROVs) in the subsea environment for the oil and gas industry.!!Sensors commonly used offshore include:!• Positioning (Surface & Acoustic)!• Attitude (Gyro Compass & Motion Reference Unit)!• Sound Velocity Profiler!• Inertial Navigation Systems (e.g. Kongsberg or PHINS) - being used more in deeper water!• Doppler Velocity Log!• Depth Sensor (Pressure zero’d on deck and attached to ROV)!• Cross-profilers, single-beam & multi-beam echo sounders!• Pipe-tracker (metal detection unit)!• Side-scan sonar!!Latency (time) is critical for the use of a USBL system to know where the ROV is.!!Sound velocity profiling takes salinity, density and temperature into account when calculating the sound velocity profile.!!Inertial navigation systems use guidance to correct drift over time. It is a low cost solution for high accuracy positioning. However, absolute accuracy is limited to the host positioning system.!!Bathymetry is used offshore to position an object. This uses an acoustic pulse from the source with the pulse time-of-flight used to calculate the range to the target ( D = 1/2 * V * T ).!!Ross also mentioned the pipe-tracker system that is essentially a sophisticated metal detector. It uses an active pulse induction system (440) and a passive tone system (350) to identify the presence of objects. Target scaling is also used. After installation, the pipe needs to be buried at a certain depth and covered by material (commonly rocks) for protection from fishing trawler equipment etc. It can be found using the pipe-tracker technology attached to an ROV. Ross noted the usefulness of this technology for a project he was involved in. A riser had disconnected and fallen to the seabed. The ROV was used for intervention and was fitted with a hydraulic cutter and subsea basket. The riser was cut into 10m sections and recovered to the vessel deck at the surface using the basket and any remaining sections were found using the pipe-tracker. The pipe-

0806514� of �10 16Hydrographic Surveying

Page 11: 0806514_Hydro Log Book

tracker picked up magnetic anomalies and flew a grid pattern to ensure the area was clear of riser pipe, allowing the operation to meet environmental regulations.!!A further case study Ross referred to was a project for TOTAL involving a spool installation. The installation area was not flat and had to be flattened in order for the project to go ahead. Sensors that were adopted for the project included:!!For surface positioning:!• Position (GNSS)!• Heading (INS)!• Pitch & Roll (INS)!• Subsea USBL (HiPAP)!!For ROV positioning:!• Position!• Contingency Positioning!• Velocity (Doppler Velocity Log)!• Heading (INS)!• Pitch & Roll (INS)!• Depth (Digiquartz)!• Sound Velocity Profiling (SVP)!• Multi-beam Sonar!• Camera!• Laser!• Obstacle Avoidance System (OAS)!!!Ross has developed an error calculator that uses inputs such as water depth, system type, precision and other system parameters to determine expected error observations at different depths. This is useful in his line of work to make effective decisions on equipment use.

0806514� of �11 16Hydrographic Surveying

Page 12: 0806514_Hydro Log Book

Hydrofest 2015! ! ! ! ! ! ! ! ! 22/04/15!!!

!

0806514� of �12 16Hydrographic Surveying

Page 13: 0806514_Hydro Log Book

Shell!The talk from Shell was presented by Ian Douglas (Head of Offshore Survey in Europe). The session took place on Wednesday the 22nd April 2015 in lecture room MT1 of Aberdeen University.!!Ian gave an overview at the start of the session and then a summary at the events conclusion.!!Ian explained the importance of position and noted that incorrect position can lead to HSSE incidents, legal costs and drilling targets being missed etc. He also looked at coordinate systems and datums within Europe. There are 18 offshore systems, 15 onshore systems and 8 datums (3 versions of ED50) currently in use and noted that the North reference needs to be clearly stated; i.e. true, grid or magnetic North.!!The lifecycle of a standard Oil and Gas project transits through; (1) Exploration, (2) Project Appraisals, (3) Development, (4) Production, and (5) Decommission.!!Identification of geo-hazards are particularly important. This can be done using 2D, 3D and 4D seismic surveys. Note, 4D examines how the reservoir performs during extraction. Traditional seismic surveys use floating seisms gun arrays that are towed from the back of the vessel. Some arrays are large enough to cover the land mass of Aberdeen. Geo-hazard surveys identify obstructions such as boulders, sands and reactive clays but is essential for identifying shallow gas that can be extremely dangerous when a rig is positioned above or nearby. Shallow gas is the man in geo-hazard that geophysicists need to identify. This is safety critical as gas in the water column can result in a loss of buoyancy resulting in vessel or rig sinking. Twisted rig legs can result from misidentification of the bottom composition as the rig can settle at a faster rate on different materials.!!He also looked at rig positioning, for example; jack-up, semi-submersible, dynamically positioned (DP) and drill ship positioning.!!Ian explained that feasibility studies are used to assess operations. For example, positioning a rig in shipping lanes and assessing the shipping activity within the area to conclude whether the operation is possible and a worthwhile distribution of resources. 3-5m accuracy is required for rig positioning and rig move operations can last for between 2-3 days or a matter of weeks for significant moves. These require thorough seabed route surveys beforehand.!!Ian also the value of subsidence monitoring and methods to perform it, as well as emergency response in the event of an oil spill, search and rescue or incident investigation.!!!

0806514� of �13 16Hydrographic Surveying

Page 14: 0806514_Hydro Log Book

Veripos!The talk from Veripos was presented by Dr. David Russell (Technology Manager). The session took place on Wednesday the 22nd April 2015 in lecture room MT1 of Aberdeen University.!!David’s talk focussed on Surface Positioning Systems. He explained the importance of georeferencing data; for defining exploration blocks, acquiring seismic data in the correct block, drilling location, and subsea infrastructure location.!!The limitations of old terrestrial-based navigation and positioning systems were; a lack of coverage, low accuracy, maintenance, and lack of redundancy.!!Inertial Navigation Systems (INS) uses dead reckoning to identify position based on where the object has been. As the system is self contained it does not suffer from interference. The system is very good in the short term. However, it drifts with time and needs positional aids to correct for this drift. The system computes 200 times per second. !!David explained that relative positioning is essential in the Oil and Gas industry for vessel to platform dynamic vessel positioning. Recent advances in laser and radar guidance have been adopted by the industry for such purposes.!!David also gave an overview of how GNSS works and the frequencies and codes that allow it to do so. He mentioned that Veripos provide data through augmentation. He explained that spatial(location) and temporal (time) errors affect positioning quality and gave satellite clock errors, receiver clock errors, ionospheric errors and satellite orbit errors as examples. Veripos augmentation system consists of 80 reference stations and control stations in Aberdeen and Singapore. Correction and integrity information are sent to uplink stations that then pass this information to geostationary satellites which broadcast the data to system users with enabled GNSS receivers!!David then covered different forms of GNSS such as DGNSS, RTK, PPP, PPP with Ambiguity Resolution (AR) and Dynamic Positioning. Veripos have tested the PPP with AR and conclude that it is capable of providing RTK accuracy without the need for a base station.!!Finally, David described surface positioning applications within the offshore Oil and Gas industry. For example, the use of GNSS to provide a vessel baseline C-O in order to calibrate the heading sensor, or using GNSS for tidal data. He concluded that a good correlation between tidal data from GNSS and tidal gauges is achievable.

0806514� of �14 16Hydrographic Surveying

Page 15: 0806514_Hydro Log Book

Fugro!The talk from Fugro was presented by Anna Fulop (Chief Geoscientist). The session took place on Wednesday the 22nd April 2015 in lecture room MT1 of Aberdeen University.!!Anna discussed the use of site surveys for rig moves, seabed lays, foundations, environmental conditions and geo-hazard identification. She bathymetry (depth, gradient and relief), sediment type (clay, sand, gravel and bedrock), obstructions (existing infrastructure, wrecks, debris and boulders) and sensitive habitats must be considered prior to the commencement of operations. Sub-seabed conditions such as geology, foundations/anchor positions and trenching must also be considered. It is also essential that geo-hazards such as shallow gas, slope stability and faulting must be identified.!!Anna covered features that can be identified through bathymetry and she noted the implications of not identifying obstructions that can cause delays in operations (e.g. incorrectly mapped telephone cabling that wrapped around drilling equipment). Environmental areas such as Coral can be initially suspected within side-scan sonar data but is generally confirmed using the camera and video equipment on ROVs and AUVs.!!Methods currently used for geological mapping of the subsea environment include (1) Remote Sensing and (2) Acoustics. Note, the range of different acoustic equipment and the different frequencies should be considered when planning a survey.!!Anna looked at high resolution seismic systems and single-channel systems. She noted the types of equipment that can be utilised as part of a seismic survey such as lingers (hull mounted), chirps (hull mounted), boomers/ sparkers (towed) and single air guns (mini & single-channel streamers). She then explained that 2D high revolution multichannel seismic systems use digital recording, require extensive data processing (more than side-scan), but are capable of obtaining deeper penetration. This data is presented using a data stacking method.!!Other tools geoscientists utilise that complement acoustics include magnetometers, gradiometers and geotechnical testing/sampling using; grab samplers, piston corers, vibrocorers, cone penetration testing, and deep boreholes (>30m bsb).!!Environmental surveys are now standard practice for many survey operations and generally make use of underwater cameras. Geoscientists and geophysicists are involved in these types of survey.!!Anna concluded her session by looking at Fugro’s Echo Surveyor IV AUV. This AUV is a Kongsberg Hugin 1000, is semi-autonomous and can operate at depths of 3000m. It often produces very detail data as it can operate close to most seabeds and this allows it to obtain much improved quality sub-bottom profiler data. She then very briefly explained the interpretation of the data and the ways that it is often presented as a standard survey project deliverable.

0806514� of �15 16Hydrographic Surveying

Page 16: 0806514_Hydro Log Book

Subsea 7!Danny Wake (Group Support Surveyor) of Subsea 7 presented this talk. The session took place on Wednesday the 22nd April 2015 in lecture room MT1 of Aberdeen University.!!Danny explained that projects are split into Capital expenditure (CAPEX) and Operational expenditure (OPEX).!!Danny also looked at pipe lay, bundle tows and installation (Subsea 7 8km bundle pipe lays).!!Different forms of pipeline survey:!• ! Route!• ! Pre-lay!• ! As Laid/ As Built!• ! General Visual Inspection (GVI)!!Out of straightness (OOS) surveys:!• ! Upheaval Buckling (UHB)!• ! Precise vertical OOS with INS!• ! Precise lateral OOS with INS - is there ant lateral shift?!!Metrology & Dimensional Control!Position and attitude of flanges:!• ! Dimensional control onshore (TLS and Photogrammetry)!• ! LBL acoustics offshore!• ! Subsea laser scanning!• ! Inertial navigation!• ! Photogrammetry!• ! Taut wire/ Diver!!Attitude monitoring of installation and GVI as it passes through the water column and rests on the seabed.!!Danny then looked at USBL and LBL techniques for subsea positioning. !Sound velocity probing:!• ! SV probe - direct reading from known baseline!• ! CTD probe - Conductivity (Salinity) Temperature Density (Pressure) probe!• ! Expendables!!Pipe-tracker used for buried pipes - essentially a large metal detector.!!!Hydrofest also consisted of talks from Scott Winning (UK Project Survey Lead for Subsea 7) and Laura McCarthy (Tendering at Fugro) that discussed tendering. Chris Almond (Senior Geophysicist at Fugro), David McLoughlin (Onshore Support at Harkand Andrews), Robin Longstaff (Bibby Offshore), and Ewelina Rams (Geomatics Lead at Bibby Offshore) completed the talks.

0806514� of �16 16Hydrographic Surveying