Method and system for accessing subterranean deposits from the surface and tools therefor

• US 8,291,974 B2
• Filed: 10/31/2007
• Issued: 10/23/2012
• Est. Priority Date: 11/20/1998
• Status: Expired due to Fees

• Current Assignee: Effective Exploration LLC
• Original Assignee: Vitruvian Exploration, LLC (Vitruvian Exploration II Holdings LLC)
• Inventors: Zupanick, Joseph A.
• Primary Examiner(s): Kreck, John
• Application Number:
  US11/982,015
• Publication Number:
  US 20080060804A1
• Time in Patent Office: 1,819 Days
• Field of Search: 166/245, 166/50, 166/313, 166/52, 166/345
• US Class Current: 166/245
• CPC Class Codes: B65G 5/00 Storing fluids in natural or artificial cavities or chambers in the earth
• CPC Class Codes: E21B 21/085 Underbalanced techniques, i.e. where borehole fluid pressure is below formation pressure
• CPC Class Codes: E21B 41/0035 Apparatus or methods for multilateral well technology, e.g. for the completion of or workover on wells with one or more lateral branches
• CPC Class Codes: E21B 41/0057 Disposal of a fluid by injection into a subterranean formation
• CPC Class Codes: E21B 43/00 Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells applicable only to water E03B
• CPC Class Codes: E21B 43/006 Production of coal-bed methane E21B43/243 takes precedence
• CPC Class Codes: E21B 43/13 specially adapted to dewatering of wells of gas producing reservoirs, e.g. methane producing coal beds
• CPC Class Codes: E21B 43/14 Obtaining from a multiple-zone well
• CPC Class Codes: E21B 43/30 Specific pattern of wells, e.g. optimising the spacing of wells
• CPC Class Codes: E21B 43/305 comprising at least one inclined or horizontal well
• CPC Class Codes: E21B 44/005 Below-ground automatic control systems
• CPC Class Codes: E21B 47/026 of penetrated ground layers
• CPC Class Codes: E21B 47/09 Locating or determining the position of objects in boreholes or wells , e.g. the position of an extending arm; Identifying the free or blocked portions of pipes
• CPC Class Codes: E21B 7/046 horizontal drilling drilling with mechanical conveying means E21B7/003
• CPC Class Codes: E21F 7/00 Methods or devices for drawing- off gases with or without subsequent use of the gas for any purpose
• CPC Class Codes: G01V 1/48 Processing data

Abstract

According to one embodiment, a system for accessing a subterranean zone from the surface includes a well bore extending from the surface to the subterranean zone, and a well bore pattern connected to the junction and operable to drain fluid from a region of the subterranean zone to the junction.

Claims

1. A system for accessing a target coal seam from a limited service area, comprising:

a plurality of well bores extending from one or more surface locations to a coal seam;

two or more of the well bores each including a well bore junction proximate to the coal and an extended drainage bore in the coal seam, each extended drainage bore operable to conduct fluids from the coal seam to the corresponding well bore junction;

each well bore junction coupled to a fluid collection area at least partially disposed below the corresponding extended drainage bore, the fluid collection area operable to collect fluids from the corresponding extended drainage bore for production to the surface; and

wherein a first area bounded by the one or more surface locations is smaller than a second area bounded by the junctions, and wherein the second area is smaller than a third area containing the extended drainage bores.

2. The system of claim 1, wherein the first area is less than approximately 500 square feet.

3. The system of claim 1, wherein the third area is at least approximately 300 acres.

4. The system of claim 1, wherein the third area is at least approximately 500 acres.

5. The system of claim 1, wherein the third area is at least approximately 600 acres.

6. The system of claim 1, wherein the third area is at least approximately 650 acres.

7. The system of claim 1, wherein the third area is at least approximately 1000 acres.

8. The system of claim 1, wherein the third area is at least approximately 1200 acres.

9. The system of claim 1, wherein the two or more well bores each including a well bore junction proximate to the target zone comprise articulated well bores.

10. The system of claim 1, wherein the well bore junctions comprise an enlarged cavity.

11. The system of claim 1, further comprising a plurality of laterals extending from the extended drainage bore to together form a well bore pattern.

12. The system of claim 11, wherein the well bore pattern comprises a pinnate well bore pattern.

13. The system of claim 1, a well bore junctions each comprising a well bore intersection.

14. A method for accessing a target coal seam from a limited service area, comprising:

drilling a plurality of well bores extending from one or more surface locations to a coal seam;

drilling for the two or more of the well bores a well bore junction proximate to the coal, an extended drainage bore in the coal seam and a fluid collection area at least partially disposed below the corresponding extended drainage bore;

conducting fluids from the coal seam through the extended drainage bores and well bore junctions to the fluid collection areas for production to the surface;

producing fluids from the fluid collection areas to the surface; and

wherein a first area bounded by the one or more surface locations is smaller than a second area bounded by the junctions, and wherein the second area is smaller than a third area containing the extended drainage bores.

15. The method of claim 14, wherein the first area is less than approximately 500 square feet.

16. The method of claim 14, wherein the third area is at least approximately 300 acres.

17. The method of claim 14, wherein the third area is at least approximately 500 acres.

18. The method of claim 14, wherein the third area is at least approximately 600 acres.

19. The method of claim 14, wherein the third area is at least approximately 650 acres.

20. The method of claim 14, wherein the third area is at least approximately 1000 acres.

21. The method of claim 14, wherein the third area is at least approximately 1200 acres.

22. The method of claim 14, drilling the two or more well bores each including a well bore junction proximate to the target zone comprising drilling articulated well bores.

23. The method of claim 14, further comprising forming an enlarged cavity at each well bore junction.

24. The method of claim 14, further comprising drilling a plurality of laterals extending from the extended drainage bore to together form a well bore pattern.

25. The method of claim 24, wherein the well bore pattern comprises a pinnate well bore pattern.