1. Designer Seismic VSP Ernie Majer (LBNL) J. Queen ( Hi –Q Geophysics) T. Dalely (LBNL) Roy Long ( DOE)

2. Acknowlegements Whiting Oil and Gas Company U.S. DOE Oil and Gas Program

3. Goal of Microhole Seismic Methods Goal of Microhole Seismic Methods Active Seismic  Define fine scale structure and lithology controlling fluid flow and content Fracture flow versus matrix flow Fault locations, bedding, pinch outs, compartment size and geometry, etc.  Discriminate fluid type and content in near and long term Oil/water/gas interface CO 2, steam, water drive efficiency, etc  Cost effective!!! Passive Seismic  Low cost means to monitor dynamics of reservoir as fluid is produced and/or injected Hydrofracture creation Interaction in the long and short term of natural fractures with induced fractures Effect and interaction of reservoir properties with changing stress  Provide validation of reservoir manipulation

4. CO 2 Project Results at Teapot Dome, WY Using VSP Microhole Technology Note: Modified from Kinder Morgan CO 2 LP Company Weathered Zone Deep Targets ( Ref. October, 2006 Issue of SEG’s Leading Edge – “Cost-effective imaging of CO2 injection with borehole seismic methods”: http://tle.geoscienceworld.org/http://tle.geoscienceworld.org/

5. Changes the way we explore for oil and gas Changes the way we monitor EOR projects Micro-Electromechanical Systems (MEMS) Microhole Technologies for Imaging Field Deployed MEMS Geophone Array

6. Demonstrate Microhole/Downward Looking VSP LANL/LBNL Objective Demonstrate improved high resolution active seismic (uses man-made sound source) Demonstrate cost effectiveness of shallow, low cost, VSP instrument boreholes for continuous monitoring with active and passive seismic (uses naturally occurring sound source) Accomplishments Shallow Microhole VSP “sees” up to 4 times (or more) shallow hole depth Up to three times better resolution than VSP in conventionally drilled boreholes (much better signal to noise ratio) Benefits Permits use of microholes for low cost, rapid VSP deployment because sensors do not need to be placed at reservoir level High resolution seismic surveys can be faster and much cheaper with permanently installed shallow, instrument boreholes Cost effective, permanent VSP boreholes could revolutionize complex reservoir characterization and long term EOR monitoring

7. RMOTC VSP compared to Surface Seismic Approximate hole depth 2 nd wall creek Lakota Red peak Tensleep Shannon 1 st wall creek 6000 feet Zero Offset Microwell VSP

9. Whiting VSP/Monitoring Purpose  Apply Microhole VSP to focus on areas of uncertainty Examine litholgy and heterogenety Valdate location of features controlling CO 2 migration  Linements  Continuity of lithology Detect changes in seismic due to CO 2 ( time lapse) Approach  Apply VSP in at least three microholes (ended up with 5)  Apply passive monitoring to determine effect of fluids on stress Logistics  No surface lines necessary  All recording performed at VSP Well

10. Noise Versus Depth for Microhole Noise Level at 500 feet Depth Is 60 dB Less Than Surface Noise

11. Wickett Field CO2 Start-Up Area (Phase 1), Section 19 of GWO Lease

12. CO 2 Sequestration Project Inject CO 2 along 2 lines Drive Oil to wells between lines Monitor CO 2 injection with Time Lapse Microhole 3D seismic survey

13. Geophone Installation Completed Microwell

14. Geophone, 1” OD

17. Acquisition Design Reflection Point Density (assumes uniform velocity)‏

18. Acquisition Design Reflection Points (assumes uniform velocity)‏

19. Actual Field Acquisition

20. Two Surveys after CO 2 Injection was Started - Summary February 2007  Vibroseis Source 10 – 100 Hz 5 sweeps 2 ms sample rate  165 Shot Points  5 Wells  825 VSP's  ~200,000 traces August 2007 Vibroseis Source 10 – 100 Hz 5 sweeps 2 ms sample rate  231 Shot Points  5 Wells  1,155 VSP's  ~275,000 traces

21. Frequency Content FFT Results for 5 Depths Between 313' & 380' SP 710 to MW_04

22. 2-D Processing Line 7 Shot Points 701 – 713 Wells 1 and 4 Line 5 Shot Points 501 – 535 Wells 3, 4, 5, &6

23. Processing for Time Lapse Reflection Amplitude Change Apply static shifts from explosive shot monitor. Edit noisy traces, sort by depth, etc. Use F-K filters to remove downgoing and enhance upgoing energy. Obtain reflection section for pre and post data For time-lapse change: normalize reflection amplitude using a shallower reflector above the Frio. Calculate change in reflection amplitude

24. Line 7 Time Lapse Analysis Compare Old and New VSP Migrations Pick Horizon at ~ -570' on Both Data Sets  Bright event above reservoir interval Flatten Both Data Sets to Common Depth Normalize Old Amplitudes  Calculate RMS amp. for picked event on both data sets  Multiply entire Old data set by ratio of RMS new /RMS old for picked event Difference the Old and New Data Approach:

25. Data After Flattening to Common Depth OLDNEW Yates Tops from Well GWO-156 Flattened Depth

26. Difference Plot of Old – New After Flatten and Normalize Yates Tops from Well GWO-156 Largest Differences Show Up Here

27. Line 5 Time Lapse Analysis Compare Old and New VSP Migrations Pick Horizon at ~ -410' on Both Data Sets  Bright event above reservoir interval Flatten Both Data Sets to Common Depth Normalize Old Amplitudes  Calculate RMS amp. for picked event on both data sets  Multiply entire Old data set by ratio of RMS new /RMS old for picked event Difference the Old and New Data Approach:

28. Comparison of Old and New Line 5 VSP Depth Migration Results OLDNEW Reservoir Interval

29. Data After Normalizing Old Amplitudes OLD NEW Yates Tops from Well GWO-156 Yates Tops from Well GWO-156 Flattened Horizon Flattened Horizon

30. Difference Plot of Old – New After Flatten and Normalize Yates Tops from Well GWO-156

31. Future Work Develop Microhole drilling technology Refine and develop processing technology (time lapse acquisition) Improve sensors and acquisition capability

33. Next Generation Sensors Wide Bband Width: DC – Kilohertz High Sensitivity: 10X Current 2008 Technology Low Cost