Dynamic connectivity analysis

• US 8,437,997 B2
• Filed: 11/21/2008
• Issued: 05/07/2013
• Est. Priority Date: 01/22/2008
• Status: Active Grant

• Current Assignee: Exxonmobil Upstream Research Company (Exxon Mobil Corporation)
• Original Assignee: Exxonmobil Upstream Research Company (Exxon Mobil Corporation)
• Inventors: Meurer, Mary Ellen, Vrolijk, Peter J., Snedden, John W., Sumpter, Lawrence T., Sweet, Michael L.
• Primary Examiner(s): Jacob, Mary C
• Assistant Examiner(s): Chad, Aniss
• Application Number:
  US12/738,427
• Publication Number:
  US 20100235154A1
• Time in Patent Office: 1,628 Days
• Field of Search: 703 9- 10
• US Class Current: 703/10
• CPC Class Codes: G01V 11/00 Prospecting or detecting by methods combining techniques covered by two or more of main groups G01V1/00 - G01V9/00
• CPC Class Codes: G01V 2210/641 Continuity of geobodies

Abstract

Methods, computer-readable mediums, and systems analyze hydrocarbon production data from a subsurface region to determine geologic time scale reservoir connectivity and production time scale reservoir connectivity for the subsurface region. Compartments, fluid properties, and fluid distribution are interpreted to determine geologic time scale reservoir connectivity and production time scale reservoir connectivity for the subsurface region. A reservoir connectivity model based on the geologic time scale and production time scale reservoir connectivity for the subsurface region is constructed, wherein the reservoir connectivity model includes a plurality of production scenarios each including reservoir compartments, connections, and connection properties for each scenario. Each of the production scenarios is tested and refined based on production data for the subsurface region.

Claims

1. A computer implemented method for analyzing connected quality of a subsurface region, said method comprising:

analyzing geologic time scale reservoir connectivity for the subsurface region;

developing a baseline reservoir connectivity model based on the geologic time scale reservoir connectivity for the subsurface region, wherein the baseline reservoir connectivity model includes determining compartments, at least one connection between compartments, and connection properties;

interpreting the compartments within the subsurface region based on production data;

analyzing fluid properties within the subsurface region based on production data;

analyzing fluid distribution within the subsurface region based on production data; and

using a computer to build a production time scale fluid connectivity model having compartments, at least one connection, and connection properties based on production data and a reconciliation of the baseline reservoir connectivity model with the production data.

2. The method of claim 1, further comprising acquiring production data from at least one well within the subsurface region.

3. The method of claim 2, further comprising estimating recoverable hydrocarbons based on the production time scale reservoir connectivity.

4. The method of claim 1, further comprising evaluating uncertainties within the connectivity models based on preproduction and production data.

5. The method of claim 4, further comprising building a multiscenario interpretation of at least one of a compartment, connection, and connection property based on evaluating uncertainties within the connectivity models.

6. The method of claim 5, wherein analyzing geologic time scale reservoir connectivity for the subsurface region and developing a baseline reservoir connectivity model based on the geologic time scale reservoir connectivity for the subsurface region, are each based on preproduction data.

7. The method of claim 6, wherein the multiscenario interpretation is based on preproduction and production data.

8. The method of claim 5, wherein analyzing fluid distribution comprises:

evaluating production start-up fluid contacts; and

documenting fluid contacts with respect to any inferred baseline conditions.

9. The method of claim 5, wherein analyzing fluid distribution comprises evaluating effectiveness of inferred connections based on downhole monitoring data.

10. The method of claim 5, wherein analyzing fluid distribution comprises:

evaluating well test and interference test data; and

reconciling single-well drainage volume, barrier, and baffle inferences with various interpreted, production scenarios.

11. The method of claim 5, wherein analyzing fluid distribution comprises interpreting fluid compositional changes based on time-lapse geochemistry.

12. The method of claim 5, wherein building multiscenario interpretations comprises establishing steady-state system fluid exits using production data.

13. The method of claim 5, wherein building multiscenario interpretations comprises establishing compartment exits and paths to system fluid exits using production data.

14. The method of claim 5, wherein building multiscenario interpretations comprises:

identifying interpreted elements that control fluid contacts; and

documenting associated uncertainties with interpreted elements.

15. The method of claim 5, wherein building multiscenario interpretations comprises:

evaluating fluid pressure evolution; and

reconciling cumulative prewell production data with fluid contacts and pressure evolution.

16. The method of claim 5, wherein building multiscenario interpretations comprises reconciling any changes in chemistry of produced fluids with the multiscenario interpretations of compartments, connections, and/or fluid properties.

17. The method of claim 5, wherein building multiscenario interpretations comprises interpreting saturation and pressure changes based on 4D seismic data.

18. The method of claim 5, wherein testing and refining of scenarios comprises:

predicting a magnitude of any change in a multiscenario interpretation for a selected point in production and with respect to a baseline condition; and

displaying the magnitude of the change.

19. The method of claim 5, wherein testing and refining of scenarios comprises building compartment specific well-log cross sections summarizing available data and deviations from inferred pressure and contact baselines.

20. The method of claim 19, wherein testing and refining of scenarios comprises building a connectivity diagram that documents compartments, connections and connection properties, and fluid exit paths for the subsurface region.

21. The method of claim 20, further comprising refining, based on three dimensional (3D) views of the subsurface region, at least one of interpreted surfaces, contact relationships, compartment boundaries, spill and breakover.

22. The method of claim 5, wherein testing and refining of scenarios comprises building a connectivity diagram that documents compartments, connections and connection properties, and fluid exit paths for the subsurface region.

23. The method of claim 22, further comprising developing and analyzing the multiple working scenarios to yield ranked and unranked suites of internally consistent connectivity conceptual models.

24. The method of claim 5, further comprising refining, based on three dimensional (3D) views of the subsurface region, at least one of interpreted surfaces, contact relationships, compartment boundaries, spill and breakover.

25. The method of claim 5, wherein testing and refining of scenarios comprises constructing multiple working scenarios and propagating dependencies for the scenarios.

26. The method of claim 5, further comprising acquiring production data for a well within the subsurface region.

27. A computer implemented method for analyzing hydrocarbon production data from a subsurface region, comprising:

analyzing geologic time scale reservoir connectivity and production time scale reservoir connectivity for the subsurface region, wherein analyzing geologic time scale and production time scale reservoir connectivity includes interpreting compartments, interpreting at least one connection, analyzing fluid properties, and analyzing fluid distribution;

using a computer to build a reservoir connectivity model based on the geologic time scale and production time scale reservoir connectivity for the subsurface region, wherein the reservoir connectivity model includes a plurality of production scenarios each including reservoir compartments, at least one connection, and connection properties, and

testing and refining each of the production scenarios based on production data for the subsurface region.

28. A computer implemented method for producing hydrocarbons from a subsurface region, comprising:

analyzing geologic time scale reservoir connectivity and production time scale reservoir connectivity for the subsurface region, wherein analyzing geologic time scale and production time scale reservoir connectivity includes interpreting compartments, analyzing fluid properties, and analyzing fluid distribution;

using a computer to build a reservoir connectivity model based on the geologic time scale and production time scale reservoir connectivity for the subsurface region, wherein the reservoir connectivity model includes a plurality of production scenarios each including reservoir compartments, at least one connection, and connection properties, and

testing and refining each of the production scenarios based on production data for the subsurface region; and

estimating an ultimate recovery amount of hydrocarbons from the subsurface region based on the production time scale reservoir connectivity.

29. The method of claim 28, further comprising:

interpreting the connectivity model to determine a formation as potentially hydrocarbon bearing; and

drilling a well to the formation interpreted in the connectivity model as potentially hydrocarbon bearing.

30. The method of claim 29, further comprising producing hydrocarbons from the well and obtaining production data from the well.

31. The method according to claim 30, further comprising estimating in-place hydrocarbons based on the geologic time scale reservoir connectivity.

32. The method according to claim 28, further comprising estimating in-place hydrocarbons based on the geologic time scale reservoir connectivity.