FORMATION CORING APPARATUS AND METHODS

• US 20100282516A1
• Filed: 05/07/2010
• Published: 11/11/2010
• Est. Priority Date: 11/02/2007
• Status: Active Grant

• Current Assignee: Schlumberger Technology Corporation (SLB)
• Original Assignee: Schlumberger Technology Corporation (SLB)
• Inventors: Erol, Gokhan, Buchanan, Steve E., Pop, Julian J., Sonne, Carsten
• Granted Patent: US 8,550,184 B2
• Time in Patent Office: Days
• US Class Current: 175/58
• CPC Class Codes: E21B 47/002 by visual inspection
• CPC Class Codes: E21B 47/0025 generating an image of the borehole wall using down-hole measurements, e.g. acoustic or electric
• CPC Class Codes: E21B 49/06 using side-wall drilling tools pressing or scrapers

Abstract

Methods comprising: lowering a downhole tool into a wellbore extending into a subterranean formation, wherein the downhole tool comprises a coring tool and a measurement tool; performing a measurement regarding the formation using the measurement tool; determining a section of interest within the formation relative to an axis of the coring tool based on the measurement; orienting a coring bit of the coring tool relative to the section of interest; and extending the oriented coring bit into the formation.

Claims

1. A method, comprising:

lowering a downhole tool into a wellbore extending into a subterranean formation, wherein the downhole tool comprises a coring tool and a measurement tool;

performing a measurement regarding the formation using the measurement tool;

determining a section of interest within the formation relative to an axis of the coring tool based on the measurement;

orienting a coring bit of the coring tool relative to the section of interest; and

extending the oriented coring bit into the formation.

2. The method of claim 1 wherein the orienting the coring bit of the coring tool relative to the section of interest comprises rotating the coring tool about the axis of the coring tool such that the coring bit is substantially radially aligned with the section of interest.

3. The method of claim 1 wherein the orienting the coring bit of the coring tool relative to the section of interest comprises adjusting an inclination angle of the coring bit with respect to the axis of the coring tool such that the coring bit is substantially aligned with the section of interest.

4. The method of claim 1 further comprising capturing a core sample from the formation using the oriented coring bit.

5. The method of claim 4 further comprising measuring a property of the captured core sample using the downhole tool.

6. The method of claim 1 wherein the measurement tool comprises a near wellbore imaging tool, wherein performing the measurement comprises using the near wellbore imaging tool to acquire an image of at least a portion of the formation, and wherein determining the section of interest is based on the acquired image.

7. The method of claim 1 wherein the measurement tool comprises a lithology tool, wherein performing the measurement comprises using the lithology tool to acquire an image of at least a portion of the formation, and wherein determining the section of interest is based on the acquired image.

8. The method of claim 1 further comprising:

determining an orientation of the coring tool within the formation; and

determining an inclination of the coring bit with respect to the axis of the coring tool.

9. The method of claim 1 wherein the orienting the coring bit of the coring tool relative to the section of interest comprises:

rotating the coring tool about the axis of the coring tool such that the coring bit is substantially radially aligned with the section of interest; and

adjusting an inclination angle of the coring bit with respect to the axis of the coring tool such that the coring bit is substantially aligned with the section of interest.

10. The method of claim 9 wherein extending the oriented coring bit into the formation comprises extending the coring bit into the formation at the inclination angle substantially aligned with the section of interest.

11. The method of claim 1 wherein lowering the downhole tool into the wellbore comprises lowering the downhole tool via wireline.

12. The method of claim 1 wherein lowering the downhole tool into the wellbore comprises lowering the downhole tool via drill pipe.

13. An apparatus, comprising:

a downhole tool configured for conveyance within a wellbore extending into a subterranean formation, wherein the downhole tool comprises a coring tool comprising;

a sidewall coring assembly having a coring bit;

an extension system configured to extend and retract the coring bit from the sidewall coring assembly; and

a rotation system configured to rotate the sidewall coring assembly relative to the coring tool;

wherein the extension system and the rotation system are independently operable.

14. The apparatus of claim 13 wherein the coring bit is configured to extend at a non-perpendicular angle with respect to an axis of the sidewall coring assembly to capture a core sample.

15. The apparatus of claim 13 wherein the extension system comprises an extension piston and an extension link arm collectively configured to extend and retract the coring bit from the sidewall coring assembly.

16. The apparatus of claim 13 wherein the rotation system comprises a rotation piston and a rotation link arm collectively configured to rotate the sidewall coring assembly with respect to an axis of the sidewall coring assembly.

17. The apparatus of claim 13 further comprising a position sensor and a controller coupled to at least one of the extension system and the rotation system.

18. The apparatus of claim 13 further comprising a coring angle control system configured to maintain the coring bit at a desired coring angle with respect to an axis of the sidewall coring assembly.

19. The apparatus of claim 18 wherein the coring angle control system comprises a handling piston configured to abut a housing within which the coring bit is disposed.

20. The apparatus of claim 18 wherein the coring angle control system comprises a valve coupled to a piston of the rotation system, wherein the valve is configured to prevent movement of the piston.