Hydrofest The Hydrographic Society in Scotland

Transcription

1 Hydrofest 2017 The Hydrographic Society in Scotland

2 Offshore Survey in the Oil and Gas Industry Hydrofest 2017 Chris Leaf Head Offshore Surveys Shell Projects and Technology, Europe

3 Presentation Overview Why Position Matters The Exploration & Production Lifecycle Seismic Surveys Rig Moves Seabed & Geohazard Surveys Construction Support Subsidence Monitoring Emergency Response Conclusions

4 Why Position Matters Around 80% of the data used by Oil & Gas companies is spatially referenced. Errors in positioning, or a poor understanding of spatial relationships, can be extremely costly and have hugely significant safety and commercial implications. Such as: Major HSSE incidents Legal costs Drilling targets missed Incorrect interpretation Understanding of reservoir characteristics Loss of asset value Loss of revenue Higher lifting costs Delays to schedules Loss of reputation

5 Is Your Survey Referenced Correctly? There are many different coordinate systems/datums/projections Coordinate Systems & Datum in Europe 18 Offshore systems 15 Onshore systems 8 Datums (3 x ED50) Vertical reference Units (metres/feet) Drill Floor Elevation, Kelly bushing? Datum, Mean Sea Level (MSL), Lowest Astronomic Tide (LAT)? North References True, Grid or Magnetic North? 5

6 How to Produce a Dry Hole Planned well at coordinates lat= , long= (WGS84 coordinate system) Actual well at coordinates lat= long= (ED50 coordinate system) m reservoir

7 The Upstream Oil & Gas Industry Lifecycle Explore Appraise Develop Produce Decommission Coordinate Reference Systems & Geodetic Parameters Geo-Info & data management GIS & Mapping Remote Sensing Emergency Response Seismic, Well and Asset Coordinates Positioning & Navigation

8 Offshore Survey in the E&P Industry Lifecycle Explore Appraise Develop Produce Decommission Scouting As Built Survey As Left Survey Seismic Seismic Seismic Environmental Baseline Environmental Monitoring Environmental Monitoring Seabed Survey Seabed Survey Seabed Survey Seabed Survey Seabed Survey Geohazard Assessment Geohazard Assessment Geohazard Assessment Geohazard Assessment Geohazard Assessment Rig Positioning Rig Positioning Rig Positioning Rig Positioning Rig Positioning Stratigraphic Coring Geotechnical Borehole Geotechnical Borehole Pipeline Routing Shallow Geotechnical Construction Support Pipeline Inspection Shallow Geotechnical Construction Support Pipeline Inspection Construction Support

9 Marine Seismic Acquisition Explore Appraise Develop Produce Decommission 2D Seismic 3D Seismic 4D Seismic Broadseis Wide Azimuth (WAZ) Multi Azimuth (MAZ) Undershoot Transition Zone (TZ) On Bottom Cable (OBC) Node Surveys Electro Magnetic (EM)

10 Marine Seismic Acquisition The Basics Survey Ship Seismic Source (airgun) Hydrophones Path of reflected sound

11 Seismic Navigation & Positioning 10 + Steerable Streamers 6 8 KMs long m lateral separation 2400 hydrophones to be positioned every 11.5 seconds For a 1000 sq km 3D survey = 135 million coordinated hydrophone position Vessel Navigation Gun Timing Control Streamer Steering Steamer positioning Real time navigation data processing Post processing

12 Seismic Navigation & Positioning Birds Vessel Guns & Paravanes Front End Acoustic Pod (Compass & depth) Active Steering Tail Buoy Seismic Airgun Gun Array Acoustic Network Instrument Room

13 Seismic Permanent Reservoir Monitoring Seismic array covers an area of 40 sq. km >120 kms of 4D seismic cable 300m between cables Designed around seabed infrastructure Available hub connectors allow for adding more cables in the future. Cable trenched into seabed Umbilical connection to platform based seismic recording system Cables trenched to an average depth of 1.1 metres 79 locations were rock dumped Seabed Array Termination Canister

14 Offshore Survey in the E&P Lifecycle Rig Positioning Explore Appraise Develop Produce Decommission Jack Up Rig Semi-Submersible Rig Dynamically Positioned (DP) Rig Drill Ship Exploration & Appraisal Development Workover Abandonment

15 Positioning Rig & Anchors in the Correct Place Ensure rig and anchors are positioned within tolerance Design Anchor Plan or jack up location Compile Well Set Procedures Confirm Location Antenna Offsets and winch offsets Gyro checks and known errors Subsea structures 1

16 Anchor Planning & Mooring Analysis All executed in GIS... Source: 2009 Annual Report

17 Front End Feasibility Studies Using GIS analysis to assess ease of access to Drilling Permits Underlying Data Protected Habitats Migratory Birds Fish & Mammals Shipping Activity Explosive Remnants of War Military Areas Difficult Easier 1

18 Offshore Survey in the E&P Lifecycle Seabed Surveys Explore Appraise Develop Produce Decommission Seabed Survey Bathymetry Survey Geohazard Survey High Resolution 2D (HR2D) Seismic Survey Shallow and Deep Geotechnical Environmental

19 Anchoring Conditions & Jack-Up Surveys Seabed surveys Design, Acquisition and Reporting: Shallow Geohazards How hard is the seabed? Seabed Relief? Obstacles & Debris 1

20 Underwater Vehicles for Seabed Surveys Autonomous Underwater Vehicle (AUV) Remotely Operated Vehicle (ROV) Image source: Designed to run multiple survey sensors simultaneously Sharp clean data possible More coverage in less time Accurate positioning is a challenge over extreme topography Not designed to run full survey sensor spread simultaneously Very high resolution data possible More time for less coverage: expensive for large areas Greater control on subsea positioning Greater flexibility for close inspection or changing survey plan 2

21 30 to 60 metre peaks Example of Seabed Survey Seafloor Bathymetry

22 Offshore Survey in the E&P Lifecycle Geohazard Survey Explore Appraise Develop Produce Decommission Drilling Hazards Shallow gas Faults Boulders Loose sands Reactive clays Other Geohazards and Hazards Buried channels Geotechnical/shallow soils Seabed topography Obstructions Habitats Archaeological Explosive Remnants of War

23 Safety Critical Activities

24 Safety Critical Activities

25 Offshore Survey in the E&P Lifecycle Offshore Construction Explore Appraise Develop Produce Decommission Pipelay Pipeline Bundle Tow & Installation J-Lay, S-Lay Manifold / Template Installation Heavy Lift Barge Plowing, Trenching & Jetting Out of Straightness Survey Seabed Intervention Metrology Spool Piece, Jumper, Riser As-Built Survey

26 Offshore Construction

27 Decommissioning & Restoration What is decommissioning? Decommissioning is the process by which options for the physical removal and disposal of structures at the end of their working life are assessed; a plan of action is formulated by the operator, approved by government and then implemented. The overall timescale for this is several years, as it needs to take into account many diverse factors and involves many organisations. a b The decommissioning of Southern North Sea fixed platforms Brent Spar: a) towed to shore, b) part of a new dock construction

28 Subsidence & Reservoir Monitoring Tilt & Settlement Surveys Continuous GPS Monitoring Air Gap Survey Scour Monitoring Seabed Geodesy Time Lapse 4D Gravity Surveys

29 Emergency Response Incident Preparedness Oil Spill Modelling Incident Response Search & Rescue Incident Investigation Common Operating Picture

30 Data Integration to Provide Situational Awareness Available anywhere in the world where Shell operates (upstream, downstream, shipping) INFRASTRUCTURE ADMIN. BOUNDARIES NAUTICAL CHARTS ENVIRONMENTAL INCIDENT FEATURES VESSELS BATHYMETRY INFRASTRUCTURE TOPOGRAPHY METOCEAN WEATHER RADAR IMAGERY DESKTOP MOBILE Unified Command Situational Status Public Information Operations WEB HARDCOPY MAPS Planning Safety Logistics Finance Static info Observed data ARCHIVE Dynamic info Predicted data 30

31 Conclusions Offshore survey is a fundamental activity within the Exploration and Production industry 80% all data managed by an E&P company is geographically referenced Always be careful with coordinates. Check, check and check again!! Offshore survey is required from cradle to grave for an E&P project Explore Appraise Develop Produce Decommission Requires a broad range of skills and competences The cost of getting it wrong can be severe $$$, HSSE, Reputational, license to operate

32 Q&A