Reservoir connectivity analysis in a 3D earth model

• US 9,874,648 B2
• Filed: 11/02/2011
• Issued: 01/23/2018
• Est. Priority Date: 02/21/2011
• Status: Active Grant

• Current Assignee: Exxonmobil Upstream Research Company (Exxon Mobil Corporation)
• Original Assignee: Exxonmobil Upstream Research Company (Exxon Mobil Corporation)
• Inventors: Braaksma, Hendrik, Cheng, Yao-Chou
• Primary Examiner(s): Shah, Kamini S
• Assistant Examiner(s): Crabb, Steven W
• Application Number:
  US13/976,364
• Publication Number:
  US 20130338984A1
• Time in Patent Office: 2,274 Days
• CPC Class Codes: G01V 1/345 Visualisation of seismic data or attributes, e.g. in 3D cubes
• 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 20/00 Geomodelling in general
• CPC Class Codes: G01V 2210/641 Continuity of geobodies
• CPC Class Codes: G01V 2210/644 Connectivity, e.g. for fluid movement
• CPC Class Codes: G06F 2111/10 Numerical modelling
• CPC Class Codes: G06F 30/20 Design optimisation, verification or simulation optimisation, verification or simulation of circuit designs G06F30/30

Abstract

There is provided a system and method for reservoir connectivity analysis in a 3D earth model. A subsurface region is identified and a baseline reservoir connectivity model is obtained from the subsurface region. Compartments and connections are determined from the baseline reservoir connectivity model using reservoir connectivity analysis, and a set of 3D objects representing the compartments and/or connections is created from the 3D earth model. A mathematical graph structure is created from the 3D objects and reservoir connectivity scenarios are evaluated based on analysis of the mathematical graph structure and 3D objects.

Claims

1. A method for reservoir connectivity analysis in a three-dimensional (3D) earth model, the method comprising:

identifying a subsurface region;

obtaining a baseline reservoir connectivity model associated with the subsurface region;

determining at least one of compartments and connections from the baseline reservoir connectivity model using reservoir connectivity analysis;

creating a set of 3D objects, in a computer system, representing the at least one of compartments and connections from the 3D earth model, wherein the creating the set of 3D objects comprises;

identifying one or more geometrical algorithms; and

using the one or more geometrical algorithms to construct the set of 3D objects based on geometrical representations;

creating a mathematical graph structure from the 3D objects, wherein the mathematical graph structure includes vertices that represent compartments or edges that represent connections, wherein the creating a mathematical graph structure comprises using graph theory algorithms and the sets of 3D objects to derive the mathematical graph structure;

evaluating reservoir connectivity scenarios based on analysis of the mathematical graph structure and 3D objects, wherein evaluating comprises identifying flow paths and topological relations among the compartments;

displaying on a monitor a representation of the compartments and the connection in the mathematical graph structure to visualize geometric relationships between compartments in the 3D earth model; and

managing hydrocarbons based on the evaluated reservoir connectivity scenarios.

2. The method recited in claim 1, further comprising compartment-bounding surfaces, flat fluid contact planes, polygons, and points as the 3D objects.

3. The method recited in claim 1, wherein the at least one of compartments and connections are determined using dynamic reservoir connectivity analysis.

4. The method recited in claim 1, further comprising creating the 3D objects from geological objects based on the reservoir connectivity scenarios.

5. The method recited in claim 1, further comprising creating the 3D objects from petro-physical properties or production information based on the reservoir connectivity scenarios.

6. The method recited in claim 1, wherein the mathematical graph structure is created and analyzed using graph-theoretic methods.

7. The method recited in claim 1, wherein the mathematical graph structure and 3D objects are modified according to analytic results or new production data.

8. The method recited in claim 1, wherein evaluating reservoir connectivity scenarios based on analysis of the mathematical graph structure and 3D objects comprises creating one or more additional constructs based on the mathematical graph structure to evaluate the reservoir connectivity scenarios.

9. The method recited in claim 1, further comprising splitting or merging compartments and the connection pathways based on the production data in the mathematical graph structure.

10. The method recited in claim 1, further comprising assigning uncertainty the connection pathways in the mathematical graph structure.

11. The method recited in claim 1, wherein displaying on the monitor comprises displaying a geometrical representation and root tree structure of compartments and the connection pathways based on the mathematical graph structure.

12. A computer system that is adapted to obtain data corresponding to a physical property of interest from a three-dimensional earth model, the computer system comprising:

a processor; and

a tangible, machine-readable storage medium that stores machine-readable instructions for execution by the processor, the machine-readable instructions comprising;

code that, when executed by the processor, is adapted to cause the processor to identify a subsurface region;

code that, when executed by the processor, is adapted to cause the processor to obtain a baseline reservoir connectivity model associated with the subsurface region;

code that, when executed by the processor, is adapted to cause the processor to determine at least one of compartments and connections from the baseline reservoir connectivity model using reservoir connectivity analysis;

code that, when executed by the processor, is adapted to cause the processor to create a set of 3D objects representing the at least one of compartments and connections from the 3D earth model, wherein the code that is adapted to cause the processor to create the set of 3D objects comprises;

code that, when executed by the processor, is adapted to cause the processor to identify one or more geometrical algorithms; and

code that, when executed by the processor, is adapted to cause the processor to use the one or more geometrical algorithms to construct the set of 3D objects based on geometrical representations

code that, when executed by the processor, is adapted to cause the processor to create a mathematical graph structure from the 3D objects, wherein the mathematical graph structure includes vertices that represent compartments or edges that represent connections and wherein the creating a mathematical graph structure comprises using graph theory algorithms and the sets of 3D objects to derive the mathematical graph structure;

code that, when executed by the processor, is adapted to cause the processor to evaluate reservoir connectivity scenarios based on analysis of the mathematical graph structure and 3D objects, wherein evaluating comprises identifying flow paths and topological relations among the compartments;

code that, when executed by the processor, is adapted to display on a monitor a representation of the compartments and the connection in the mathematical graph structure to visualize geometric relationships between compartments in the 3D earth model; and

code that, when executed by the processor, is adapted to cause the processor to manage hydrocarbons based on the evaluated reservoir connectivity scenarios.

13. The system recited in claim 12, further comprising compartment-bounding surfaces, flat fluid contact planes, polygons, and points as the 3D objects.

14. The system recited in claim 12, wherein the at least one of compartments and connections are determined using dynamic reservoir connectivity analysis.

15. The system recited in claim 12, further comprising creating the 3D objects from geological objects based on the reservoir connectivity scenarios.

16. The system recited in claim 12, further comprising creating the 3D objects from petro physical properties or production information based on the reservoir connectivity scenarios.

17. The system recited in claim 12, wherein the mathematical graph structure is created and analyzed using graph-theoretic methods.

18. The system recited in claim 12, wherein the mathematical graph structure and 3D objects are modified according to analytic results or new production data.

19. A non-transitory, computer readable medium comprising code configured to direct a processor to:

identify a subsurface region;

obtain a baseline reservoir connectivity model associated with the subsurface region;

determine at least one of compartments and connections from the baseline reservoir connectivity model using reservoir connectivity analysis;

create a set of 3D objects representing the at least one of compartments and connections from the 3D earth model, wherein the creation of the set of 3D objects comprises identifying one or more geometrical algorithms and using the one or more geometrical algorithms to construct the set of 3D objects based on geometrical representations;

create a mathematical graph structure from the 3D objects, wherein the mathematical graph structure includes vertices that represent compartments or edges that represent connections, wherein the creation of the mathematical graph structure comprises using graph theory algorithms and the sets of 3D objects to derive the mathematical graph structure;

evaluate reservoir connectivity scenarios based on analysis of the mathematical graph structure and 3D objects, wherein the evaluation comprises identifying flow paths and topological relations among the compartments;

display on a monitor a representation of the compartments and the connection in the mathematical graph structure to visualize geometric relationships between compartments in the 3D earth model; and

manage hydrocarbons based on the evaluated reservoir connectivity scenarios.

20. The non-transitory, computer readable medium recited in claim 19, further comprising compartment-bounding surfaces, flat fluid contact planes, polygons, and points as 3D objects.

21. The non-transitory, computer readable medium recited in claim 19, wherein the at least one of compartments and connections are determined using dynamic reservoir connectivity analysis.

22. The non-transitory, computer readable medium recited in claim 19, further comprising creating the 3D objects from geological objects based on reservoir connectivity scenarios.

23. The non-transitory, computer readable medium recited in claim 19, further comprising creating the 3D objects from petro physical properties or production information based on reservoir connectivity scenarios.

24. The non-transitory, computer readable medium recited in claim 19, wherein the mathematical graph structure is created and analyzed using graph-theoretic methods.

25. The non-transitory, computer readable medium recited in claim 19, wherein the graphical representation is modified according to analytic results or new production data.