Method and system for accessing subterranean zones from a limited surface area

• US 6,425,448 B1
• Filed: 01/30/2001
• Issued: 07/30/2002
• Est. Priority Date: 01/30/2001
• Status: Expired due to Term

• Current Assignee: Effective Exploration LLC
• Original Assignee: CDX Gas LLC (EnerVest Ltd.)
• Inventors: Zupanick, Joseph A., Rial, Monty H.
• Primary Examiner(s): Bagnell, David
• Assistant Examiner(s): KRECK, JOHN J
• Application Number:
  US09/773,217
• Publication Number:
  US 20020100616A1
• Time in Patent Office: 546 Days
• Field of Search: 175/61, 175/57, 175/62, 166/50, 166/52, 166/245
• US Class Current: 175/61
• CPC Class Codes: E21B 43/006 Production of coal-bed methane E21B43/243 takes precedence
• CPC Class Codes: E21B 43/305 comprising at least one inclined or horizontal well
• CPC Class Codes: E21B 7/046 horizontal drilling drilling with mechanical conveying means E21B7/003

Abstract

A method and system for accessing subterranean zones from the surface includes a substantially vertical well bore extending from the surface to a target zone, and an articulated well bore extending from the substantially vertical well bore to the target zone. The articulated well bore diverges from the substantially vertical well bore between the surface and the target zone. The system also includes a well bore pattern extending from the articulated well bore in the target zone operable to collect resources from the target zone. The system also includes a subsurface channel operable to communicate resources from the well bore pattern to the substantially vertical well bore. The system further includes a vertical pump disposed in the substantially vertical well bore and operable to lift resources collected in the substantially vertical well bore to the surface.

Claims

1. A method for accessing a subsurface formation from the surface, comprising:

providing a substantially vertical well bore from a surface to a target zone;

providing a first articulated well bore extending from the substantially vertical well bore to the target zone, the first articulated well bore diverging from the substantially vertical well bore between the surface and the target zone;

providing a second articulated well bore extending from the substantially vertical well bore and intersecting the first articulated well bore at a junction proximate the target zone; and

forming a well bore pattern extending from the junction into the target zone.

2. The method of claim 1, further comprising removing resources from the target zone through the substantially vertical well bore.

3. The method of claim 1, wherein forming the well bore pattern comprises forming the well bore pattern through the first articulated well bore.

4. The method of claim 1, wherein forming the well bore pattern comprises forming the well bore pattern through the second articulated well bore.

5. The method of claim 1, further comprising forming an enlarged cavity in the target zone at an end of the well bore pattern proximate to the first and second articulated well bores, the second articulated well bore communicating between the substantially vertical well bore and the enlarged cavity.

6. The method of claim 5, wherein forming the enlarged cavity comprises forming an enlarged diameter cavity.

7. The method of claim 5, wherein forming the enlarged cavity comprises forming the enlarged cavity substantially within a coal seam.

8. The method of claim 5, wherein forming the well bore pattern comprises:

forming a main well bore extending from the enlarged cavity into the target zone; and

forming a plurality of lateral well bores extending outwardly from opposite sides of the main well bore.

9. The method of claim 8, wherein forming the lateral well bores comprises forming the lateral well bores substantially equally spaced apart from each other.

10. The method of claim 1, wherein forming the well bore pattern comprises forming a pinnate well bore pattern.

11. The method of claim 10, wherein forming the pinnate well bore pattern comprises forming a plurality of lateral well bores extending from a main well bore into the target zone.

12. The method of claim 1, further comprising:

disposing a vertical pump in the substantially vertical well bore; and

removing resources collected in the substantially vertical well bore to the surface using the vertical pump.

13. The method of claim 12, wherein disposing the vertical pump comprises providing a sucker-rod pump.

14. A method for extracting resources from a subsurface formation, comprising:

providing a substantially vertical well bore from a surface to a first target zone and a second target zone;

providing a first articulated well bore extending from the substantially vertical well bore to the first target zone, the first articulated well bore diverging from the substantially vertical well bore between the surface and the first target zone;

providing a second articulated well bore extending from the substantially vertical well bore and intersecting the first articulated well bore at a first junction proximate the first target zone;

providing a first well bore pattern extending from the first junction into the first target zone;

removing resources from the first target zone through the substantially vertical well bore;

providing a third articulated well bore extending from the substantially vertical well bore to the second target zone, the third articulated well bore diverging from the substantially vertical well bore between the surface and the second target zone;

providing a fourth articulated well bore extending from the substantially vertical well bore and intersecting the third articulated well bore at a second junction proximate the second target zone;

providing a second well bore pattern extending from the second junction into the second target zone; and

removing resources from the second target zone through the substantially vertical well bore.

15. The method of claim 14, wherein providing the first and second well bore patterns comprises forming the first and second well bore patterns through the respective first and third articulated well bores.

16. The method of claim 14, further comprising:

providing a first cavity in the first target zone at an end of the first well bore pattern proximate to the first junction, the second articulated well bore communicating between the substantially vertical well bore and the first cavity; and

providing a second cavity in the second target zone at an end of the second well bore pattern proximate to the second junction, the fourth articulated well bore communicating between the substantially vertical well bore and the second cavity.

18. The method of claim 14, wherein providing the second and fourth articulated well bores comprises providing the second and fourth articulated well bores disposed substantially within the respective first and second target zones.

19. The method of claim 14, wherein providing the first and second well bore patterns comprise providing pinnate well bore patterns.

17. The method of 16, wherein providing the first and second cavities comprises providing the first and second cavities disposed substantially within the respective first and second target zones.

20. A system for accessing a subsurface formation from the surface, comprising:

a first well bore extending downwardly from the surface;

a second well bore extending from the first well bore to a target zone, the second well bore diverging from the first well bore between the surface and the target zone;

a third well bore extending from the first well bore and intersecting the second well bore at a junction proximate the target zone; and

a well bore pattern extending from the junction into the target zone.

21. The system of claim 20, further comprising a cavity disposed within the target zone at an end of the well bore pattern proximate to the junction, the third well bore providing communication between the cavity and the first well bore.

22. The system of claim 20, further comprising a pump disposed in the first well bore and operable to lift resources collected in the first well bore to the surface.

23. The system of claim 22, wherein the pump comprises a sucker-rod pump.

24. The system of claim 20, wherein the third well bore is disposed substantially within the target zone.

25. The system of claim 20, wherein the well bore pattern comprises a pinnate well bore pattern.

26. The system of claim 20, wherein the well bore pattern comprises:

a main well bore extending from the junction; and

a plurality of lateral well bores extending outwardly from the main well bore.

27. The system of claim 26, wherein the plurality of lateral well bores are disposed substantially equally spaced apart from each other.

28. A system for extracting resources from a subsurface formation, comprising:

a substantially vertical well bore extending from a surface to a first target zone and a second target zone;

a first articulated well bore extending from the substantially vertical well bore to the first target zone, the first articulated well bore diverging from the substantially vertical well bore between the surface and the first target zone;

a first well bore pattern extending from the first articulated well bore in the first target zone operable to collect resources from the first target zone;

a second articulated well bore operable to communicate resources from the first well bore pattern to the substantially vertical well bore;

a third articulated well bore extending from the substantially vertical well bore to the second target zone, the third articulated well bore diverging from the substantially vertical well bore between the surface and the second target zone;

a second well bore pattern extending from the third articulated well bore in the second target zone operable to collect resources from the second target zone;

a fourth articulated well bore operable to communicate resources from the second well bore pattern to the substantially vertical well bore; and

a vertical pump disposed in the substantially vertical well bore and operable to lift the resources collected in the substantially vertical well bore to the surface.

29. The system of claim 28, further comprising:

a first cavity disposed within the first target zone at an end of the first well bore pattern proximate to the first articulated well bore, the second articulated well bore operable to communicate the resources from the first cavity to the substantially vertical well bore; and

a second cavity disposed within the second target zone at an end of the second well bore pattern proximate to the third articulated well bore, the fourth articulated well bore operable to communicate the resources from the second cavity to the substantially vertical well bore.

30. The system of claim 28, wherein the second and fourth articulated well bore are disposed substantially within the respective first and second target zones.

31. The system of claim 28, wherein the first and second well bore patterns comprise pinnate well bore patterns.

32. The system of claim 31, wherein each pinnate well bore pattern comprises a plurality of lateral well bores extending from a respective main well bore disposed substantially within a respective target zone.

33. The system of claim 28, wherein the vertical pump comprises a sucker-rod pump.

34. The system of claim 28, wherein each of the first and second well bore patterns comprise:

a substantially horizontal diagonal well bore extending from a first end of an area of a subterranean zone to a second end of the area of the subterranean zone; and

a plurality of lateral well bores extending in spaced apart relation to each other from the diagonal well bore to a periphery of the area.

35. The system of claim 34, wherein the first end of the area is disposed proximate the respective first and third articulated well bores, and wherein a length of the lateral well bores progressively decreases as a distance between the lateral well bore and the first end increases.