Oil spill leakage avoidance with real time seismic monitoring. Helge Brandsæter, President OCTIO AS

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1 Oil spill leakage avoidance with real time seismic monitoring Helge Brandsæter, President OCTIO AS

2 Injection wells - Pitfalls Oseberg - Norway Frade Brazil Veslefrikk Norway Tordis - Norway

3 Challenges in Northern Norwegian waters From the Wisting field, Source: Halfdan Carstens, Geo635 Pockmarks, The Barents Sea, Source: Mareano project report

4 Drilling Hazards Particularly applicable for: Areas with shallow overburden with young or eroded sediments Northern Norwegian waters, Brazil, West Africa

5 Up to 25% of wells ends up as service or injection wells Challenge: Production and Environmental risk Injection systems raise the reservoir pressure Can cause cap rock integrity issues and subsequent failure Can result in potential environmental contamination 131 An estimated 25% of offshore wells in Europe can be considered service wells (water or waste injection) 1 Production loss and environmental risk / penalties ~15% of operational discharge injection wells in the NCS are shut in because of established or suspected leaks European Offshore Wells Drilled Annually Predicted 1.8% annual increase Simmons Market Intelligence 2 Norwegian Climate and Polution Agency (Klif) 3 Drilling and Production Outlook, 2010

6 System Objectives Ensure spill avoidance by: Monitoring of stress changes Real time monitoring of microseismic events Real time monitoring of failures in CapRock and flow barriers Most important: Provide alarms in the event that critical barriers are effected, so that appropriate actions can be taken

7 The ReM System

8 Ethernet on the seafloor: Open digital system Interfaces third party sensors Connects to subsea infrastructure Expandable, starting from a small focused system to a large full-field system =>The digital oil field becomes a reality!

9 Active and Passive operation Active mode On demand surveys for IOR or CapRock integrity monitoring Passive mode 24/7 passive monitoring for detection of microseismic events caused by: Fault reactivation CapRock failures and leaks to surface

10 Remotely operated 24/7 Data in real-time to client s office System operation and QC in client s office and/or OCTIO s operation room Unmanned system on the rig

11 The SWIM project

12 Oseberg area - Location OSC C-4 A Source : Statoil

13 Survey on Oseberg C after observation of subsea craters OMR C OMR B OMR A High concentration of EOM (Extracted Organic Material) Source: Statoil

14 Oseberg C, Seafloor changes Source: Statoil

15 Seismic Data across the old CRI well at Oseberg C Seismic data(1982) before outof-zone injection event Seismic data (2011) after outof-zone injection event Utsira Utsira Injection intervall Injection intervall Source: Statoil

16 The SWIM project principles Onshore for real time processing Detect fractures before they reach surface Source: Statoil

17 Perforation shot Vertical, Hz Expected P Multiples: - P P (just where S expected) Travel time curves shifted up, not to hide the signal

18 Fracking from water injection test

19 Operational Scenario Real time console Operational Team Baseline Microseismic Pressure Other activity Alert level Graded event notifications Sets alert levels Evaluates fracture positions and speed of fracture propagation Requests more detailed fracture analysis if needed If fracturing reaches critical levels appropriate actions will be instigated within 3 hours of notification

20 Cuttings Re-Injection or Transport Onshore? Transport onshore Re-injection Transportation costs scenario based on North Sea case (yearly cost): All inclusive transportation cost: USD 12 mill Lost drilling awaiting weather for transport: USD 6.5 mill Total: USD18.5 mill Yearly monitoring cost USD 2-3 mill Additional benefits: 2 years extension of life time of injection well Reinjection of sloop saving USD 50k per week Potentially less production downtime

21 Conclusions Focused well monitoring facilitates: Safer injection (for IOR) in case CapRock integrity is challenged Safe injection of cuttings and waste water Well integrity monitoring during drilling and production Most important focused monitoring improves the bottom line