METHOD OF SUBSURFACE RESERVOIR FRACTURING USING ELECTROMAGNETIC PULSE ENERGY

• US 20150192005A1
• Filed: 12/22/2014
• Published: 07/09/2015
• Est. Priority Date: 01/08/2014
• Status: Abandoned Application

• Current Assignee: Husky Oil Operations Limited (Cenovus Energy Incorporated)
• Original Assignee: Husky Oil Operations Limited (Cenovus Energy Incorporated)
• Inventors: Saeedfar, Amin
• Application Number:
  US14/578,922
• Publication Number:
  US 20150192005A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: E21B 36/00 Heating, cooling or insulating arrangements for boreholes or wells, e.g. for use in permafrost zones
• CPC Class Codes: E21B 43/24 using heat, e.g. steam injection
• CPC Class Codes: E21B 43/2401 by means of electricity
• CPC Class Codes: E21B 47/13 by electromagnetic energy, e.g. radio frequency
• CPC Class Codes: H01Q 1/04 Adaptation for subterranean or subaqueous use

Abstract

A method for initiating and/or propagating fractures in a hydrocarbon reservoir, to improve fluid-flow permeability and hydrocarbon production. The method comprises the use of at least one electromagnetic energy pulse to both heat the reservoir rock and water within, causing thermal pressurization, and initiate electrokinetic pressurization.

Claims

1. A method for initiating and propagating fractures in a hydrocarbon reservoir, the method comprising the steps of:

a. applying at least one electromagnetic energy pulse to a portion of the reservoir;

b. allowing application of the at least one electromagnetic energy pulse to expand pore fluids within the portion of the reservoir;

c. allowing the expansion of the pore fluids to increase pore pressure; and

d. allowing the increased pore pressure to create mechanical stresses in the portion of the reservoir exceeding fracture stress of the portion of the reservoir, initiating and propagating fractures in the reservoir.

2. The method of claim 1 wherein a series of the electromagnetic energy pulses are applied to the portion of the reservoir.

3. The method of claim 1 wherein a plurality of the electromagnetic energy pulses are applied to the portion of the reservoir.

4. The method of claim 1 wherein the electromagnetic energy pulses are periodically applied to the portion of the reservoir.

5. The method of claim 1 further comprising the step before step a of determining a suitable pulse strength for the at least one electromagnetic energy pulse.

6. The method of claim 1 wherein the at least one electromagnetic energy pulse is applied by radiating the at least one electromagnetic energy pulse so as to propagate the at least one electromagnetic energy pulse at least partially through the portion of the reservoir.

7. The method of claim 1 wherein the expansion of the pore fluids results from thermal pressurization and electrokinetic pressurization.

8. The method of claim 1 wherein the expansion of the pore fluids results at least partially from vaporization of connate water in the portion of the reservoir.

9. The method of claim 1 wherein the fractures comprise micro-cracks.

10. The method of claim 9 wherein the micro-cracks reduce strength of the portion of the reservoir, enabling propagation of the fractures.

11. A method for improving permeability in a hydrocarbon reservoir, the method comprising the steps of:

a. applying at least one electromagnetic energy pulse to a portion of the reservoir;

b. allowing application of the at least one electromagnetic energy pulse to expand pore fluids within the portion of the reservoir;

c. allowing the expansion of the pore fluids to increase pore pressure; and

d. allowing the increased pore pressure to create mechanical stresses in the portion of the reservoir exceeding fracture stress of the portion of the reservoir, fracturing the portion of the reservoir to improve the permeability.

12. The method of claim 11 wherein a series of the electromagnetic energy pulses are applied to the portion of the reservoir.

13. The method of claim 11 wherein a plurality of the electromagnetic energy pulses are applied to the portion of the reservoir.

14. The method of claim 11 wherein the electromagnetic energy pulses are periodically applied to the portion of the reservoir.

15. The method of claim 11 further comprising the step before step a of determining a suitable pulse strength for the at least one electromagnetic energy pulse.

16. The method of claim 11 wherein the at least one electromagnetic energy pulse is applied by radiating the at least one electromagnetic energy pulse so as to propagate the at least one electromagnetic energy pulse at least partially through the portion of the reservoir.

17. The method of claim 11 wherein the expansion of the pore fluids results from thermal pressurization and electrokinetic pressurization.

18. The method of claim 11 wherein the expansion of the pore fluids results at least partially from vaporization of connate water in the portion of the reservoir.

19. The method of claim 11 wherein the mechanical stresses reduce shear strength of the portion of the reservoir, causing the fracturing.

20. The method of claim 11 wherein the mechanical stresses cause tensile failure of the portion of the reservoir, causing the fracturing.

21. A method for improving production of hydrocarbon from a reservoir, the method comprising the steps of:

a. applying at least one electromagnetic energy pulse to a portion of the reservoir;

b. allowing application of the at least one electromagnetic energy pulse to expand pore fluids within the portion of the reservoir;

c. allowing the expansion of the pore fluids to increase pore pressure;

d. allowing the increased pore pressure to create mechanical stresses in the portion of the reservoir exceeding fracture stress of the portion of the reservoir, initiating and propagating fractures in the reservoir; and

e. producing the hydrocarbon through the fractures.

22. The method of claim 21 wherein a series of the electromagnetic energy pulses are applied to the portion of the reservoir.

23. The method of claim 21 wherein a plurality of the electromagnetic energy pulses are applied to the portion of the reservoir.

24. The method of claim 21 wherein the electromagnetic energy pulses are periodically applied to the portion of the reservoir.

25. The method of claim 21 further comprising the step before step a of determining a suitable pulse strength for the at least one electromagnetic energy pulse.

26. The method of claim 21 wherein the at least one electromagnetic energy pulse is applied by radiating the at least one electromagnetic energy pulse so as to propagate the at least one electromagnetic energy pulse at least partially through the portion of the reservoir.

27. The method of claim 21 wherein the expansion of the pore fluids results from thermal pressurization and electrokinetic pressurization.

28. The method of claim 21 wherein the expansion of the pore fluids results at least partially from vaporization of connate water in the portion of the reservoir.

29. The method of claim 21 wherein the fractures comprise micro-cracks.

30. The method of claim 29 wherein the micro-cracks reduce strength of the portion of the reservoir, enabling propagation of the fractures.

31. A method of hydrocarbon reservoir stimulation, the method comprising the steps of:

a. applying at least one electromagnetic energy pulse to a portion of a reservoir;

b. allowing application of the at least one electromagnetic energy pulse to expand pore fluids within the portion of the reservoir;

c. allowing the expansion of the pore fluids to increase pore pressure;

d. allowing the increased pore pressure to create mechanical stresses in the portion of the reservoir exceeding fracture stress of the portion of the reservoir, initiating and propagating fractures in the reservoir; and

e. producing hydrocarbon through the fractures.

32. The method of claim 31 wherein a series of the electromagnetic energy pulses are applied to the portion of the reservoir.

33. The method of claim 31 wherein a plurality of the electromagnetic energy pulses are applied to the portion of the reservoir.

34. The method of claim 31 wherein the electromagnetic energy pulses are periodically applied to the portion of the reservoir.

35. The method of claim 31 further comprising the step before step a of determining a suitable pulse strength for the at least one electromagnetic energy pulse.

36. The method of claim 31 wherein the at least one electromagnetic energy pulse is applied by radiating the at least one electromagnetic energy pulse so as to propagate the at least one electromagnetic energy pulse at least partially through the portion of the reservoir.

37. The method of claim 31 wherein the expansion of the pore fluids results from thermal pressurization and electrokinetic pressurization.

38. The method of claim 31 wherein the expansion of the pore fluids results at least partially from vaporization of connate water in the portion of the reservoir.

39. The method of claim 31 wherein the fractures comprise micro-cracks.

40. The method of claim 39 wherein the micro-cracks reduce strength of the portion of the reservoir, enabling propagation of the fractures.