HYDRAULIC FRACTURING WHILE DRILLING AND/OR TRIPPING
Methods and apparatuses for hydraulically fracturing a subterranean wellbore while drilling and/or tripping are disclosed. A method for hydraulically fracturing a subterranean formation may include rotating a drill string to drill the wellbore and hydraulically fracturing the subterranean formation at a plurality of axially spaced locations along the wellbore while tripping the drill string out of the wellbore. The drill string may include a hydraulic fracturing assembly. The hydraulic fracturing operation may include translating the drill string in an uphole direction so that a set of frac ports in the hydraulic fracturing assembly is adjacent a region of the formation selected for fracturing, expanding at least one pair of packers to seal an annular region of the wellbore exterior to the frac ports, and pumping fracturing fluid downhole through the frac ports to hydraulically fracture the subterranean formation.
None.
FIELD OF THE INVENTIONDisclosed embodiments relate generally to methods and apparatuses for hydraulically fracturing a subterranean formation and more particularly to methods and apparatuses for hydraulically fracturing a subterranean formation while drilling and/or while tripping a drill string out of a well.
BACKGROUND INFORMATIONWellbores are commonly drilled through subterranean formations to enable the extraction of hydrocarbons. Hydraulic fracturing is known to significantly increase the production rates of hydrocarbons in certain subterranean formation types (e.g., those having low fluid and/or gas permeability such as deep shale formations). In one common hydraulic fracturing operation, high pressure fluids are used to create localized fractures in the formation. The fluids may further include proppants (such as sand) to hold open the fractures after the pump pressure is removed thereby enabling hydrocarbons to flow from the fractured formation into the wellbore.
The overall process for creating a hydraulically fractured wellbore commonly includes two or three primary operations; a drilling operation, an optional casing operation, and hydraulic fracturing operations. These operations generally require distinct surface and downhole equipment (sometimes even including distinct surface rigging) and commonly make use of different engineering teams. The overall process to create a productive wellbore can therefore be time consuming and expensive as it commonly requires removing the drilling and casing equipment and moving in and rigging up the fracturing equipment in addition to performing the actual drilling, casing, and fracturing operations.
Therefore, there's a need in the art for improved overall process for creating a hydraulically fractured wellbore.
SUMMARYMethods and apparatuses for hydraulically fracturing a subterranean wellbore are disclosed. In one embodiment a method for hydraulically fracturing a subterranean formation includes rotating a drill string in the subterranean wellbore to drill the wellbore and hydraulically fracturing the subterranean formation at a plurality of axially spaced locations along the wellbore while tripping the drill string out of the wellbore. The drill string includes a hydraulic fracturing assembly. The hydraulic fracturing operation includes translating the drill string in an uphole direction so that a set of frac ports in the hydraulic fracturing assembly is adjacent a region of the formation selected for fracturing, expanding at least one pair of packers to seal an annular region of the wellbore exterior to the frac ports, pumping fracturing fluid downhole through the frac ports to hydraulically fracture the subterranean formation. The hydraulic fracturing process may then be repeated at a plurality of axially spaced locations along the wellbore while tripping the drill string out of the wellbore.
The disclosed embodiments may provide various technical advantages. In particular, the disclosed methods may enable a significant time and cost savings to be realized when drilling and hydraulically fracturing a subterranean wellbore. The disclosed embodiments may further enable a rig having a smaller foot print to be utilized due to sharing of the surface equipment between the drilling and fracturing operations. The disclosed embodiments may further reduce crew requirements as field personnel may be cross trained to perform both drilling and fracturing operations.
This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.
For a more complete understanding of the disclosed subject matter, and advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
The rig 20 may include a derrick and a hoisting apparatus for raising and lowering a drill string 30, which, as shown, extends into wellbore 40 and includes a drill bit 32, a number of downhole tools 52, 54, and 56, and a hydraulic fracturing assembly 100. The downhole tools 52, 54, and 56 may include substantially any suitable downhole tools, for example, including a steering tool such as a rotary steerable tool, a logging while drilling (LWD) tool, a measurement while drilling tool (MWD) tool, a downhole drilling motor, a downhole telemetry system, and the like. The disclosed embodiments are not limited in these regards. It will be understood by those of ordinary skill in the art that the deployment illustrated on
It will be understood that the disclosed hydraulic fracturing assembly embodiments do not necessary include multiple packers as depicted on
Method 200 is now described in further detail with respect to
In the depicted embodiment the hydraulic fracturing assembly includes first and second, upper and lower, sets of frac ports 130. It will be understood that in such embodiments (having multiple sets of frac ports) the zones of interest may be hydraulically fractured sequentially in a multistep operation as depicted on
The decision regarding whether to fracture adjacent zones sequentially or simultaneously (and how many zones may be fractured simultaneously) may be based on numerous operational factors. For example, the decision may depend upon the existing rig or derrick height. Larger rigs may generally accommodate a hydraulic fracturing assembly including multiple fracture ports and may therefore be suitable for simultaneous hydraulic fracturing (while a smaller rig may not). The decision may also depend upon the pump pressure required to propagate the fractures and the desired depth of such fractures. For certain formations or formation types (e.g., those requiring higher pressures) it may be advantageous to fracture the zones sequentially as depicted in
With continued reference to
While not depicted in flowchart 200, the method may optionally further include running a casing string into the drilled and hydraulically fractured wellbore. For example, slotted liners (casing) may be run in and deployed in the fractured regions (e.g., after the fracturing operation has been finished and the drill string removed the wellbore). The casing string may be supported in the wellbore by a plurality of modular swellable isolation packers (such as the ResPack available from Schlumberger) which may be formed from a polymer that swells in the presence of wellbore fluids. The casing string may alternatively be unsupported in the wellbore. Moreover, it will be understood that disclosed embodiments do not necessarily include a casing step. In certain embodiments the well plan may call for an open hole or barefoot completion (i.e., a completion not including a wellbore liner or casing).
One advantage of the disclosed methods is that they tend to significantly reduce the time to first production (and therefore tend to also provide significant cost savings in bringing a wellbore to production).
A conventional hydraulic fracturing operation is depicted by the dotted line at 410. This operation includes an extended time delay at 412 (also referred to in the art as downtime or flat time). This time delay represents the time required to break down the drilling equipment and drilling rig (and perhaps move it off location) and then the time required to move in and rig up the fracturing equipment (including the rigging, the fracturing fluid pumps, and the fracturing fluid holding and blending systems) used in the conventional fracturing operation. A single entry multizone fracturing operation is depicted at 414. In this operation multiple fractures are imparted to the portion of the wellbore represented by the third stage 402C. The conventional multizone hydraulic fracturing assembly is then removed from the wellbore upon the completion of the operation at 416.
The disclosed fracturing methodology is depicted by the dashed line at 420. This operation includes a comparatively short time delay 422 in which the surface system is reconfigured for pumping fracturing fluid downhole (this may be as simple as opening and/or closing one or more valves (such as valve 155 on
It will be understood that the time savings 430 depicted on
Although fracturing while drilling and/or tripping and certain advantages thereof have been described in detail, it should be understood that various changes, substitutions and alternations can be made herein without departing from the spirit and scope of the disclosure as defined by the appended claims.
Claims
1. A downhole hydraulic fracturing assembly comprising:
- a downhole tool body including a through bore and configured for coupling with a drill string;
- at least first and second axially spaced packers deployed on the tool body;
- a first pair of under gauge stabilizers deployed axially about the first packer and a second pair of under gauge stabilizers deployed axially about the second packer;
- a set of frac ports deployed axially between the first and second packers, the frac ports configured to selectively actuate between first and second, open and closed positions, the frac ports providing fluid communication between the through bore and an external region of the tool when in the open position;
- a valve deployed in the through bore of the tool body, the valve configured to selectively actuate between first and second, open and closed positions, the valve providing fluid communication between first and second axial ends of the through bore when in the open position.
2. The assembly of claim 1, wherein the valve is deployed on a downhole end of the tool body.
3. The assembly of claim 1, further comprising:
- a third axial spaced packer deployed on the tool body;
- a third pair of under gauge stabilizers deployed axially about the third packer; and
- a second sets of frac ports deployed axially between the second and third packers.
4. A method for drilling and hydraulically fracturing a subterranean wellbore, the method comprising:
- (a) coupling the downhole hydraulic fracturing assembly of claim 1 above a drill bit on a drill string;
- (b) deploying the drill string in a subterranean wellbore;
- (c) closing the frac ports, opening the valve, and rotating the drill string to drill a subterranean wellbore; and
- (d) opening the frac ports, closing the valve, expanding the packers, and pumping fracturing fluid through the frac ports to hydraulically fracture the subterranean formation.
5. A method for drilling and hydraulically fracturing a subterranean wellbore, the method comprising:
- (a) coupling the downhole hydraulic fracturing assembly of claim 1 above a drill bit and a logging while drilling tool on a drill string;
- (b) deploying the drill string in a subterranean wellbore;
- (c) closing the frac ports, opening the valve, and rotating the drill string to drill a subterranean wellbore;
- (d) evaluating logging while drilling data obtained while drilling in (c) to identify at least one region for fracturing;
- (e) lifting the drill bit off bottom such that the frac ports are adjacent the region for fracturing; and
- (f) opening the frac ports, closing the valve, expanding the packers, and pumping fracturing fluid through the frac ports to hydraulically fracture the subterranean formation.
6. The method of claim 5, further comprising:
- (g) at least partially contracting the packers and lifting the drill bit further off the bottom such that the frac ports are adjacent a second region for fracturing; and
- (h) repeating (f).
7. A combined drilling fluid and fracturing fluid surface system for a combined downhole drilling and hydraulic fracturing operation, the surface system comprising:
- a pumping sub-system including at least one pump for pumping drilling fluid or fracturing fluid downhole;
- a drilling fluid sub-system including a drilling fluid tank;
- a fracturing fluid sub-system including a blender in fluid communication with a fracture fluid container and a proppant container;
- a flushing fluid sub-system including a flushing fluid tank; and
- a multiport valve configured to selectively hydraulically couple the drilling fluid sub-system, the fracturing fluid sub-system, or the flushing fluid sub-system with the pumping sub-system.
8. The surface system of claim 7, further comprising a cement blender hydraulically coupled to the multiport valve.
9. The surface system of claim 7, wherein the drilling fluid sub-system further comprises a degasser, a desilter, a desander, and a shale shaker;
10. A method for hydraulically fracturing a subterranean formation, the method comprising:
- (a) deploying a drill string in a subterranean wellbore, the drill string including a drill bit and a hydraulic fracturing assembly, the hydraulic fracturing assembly in hydraulic communication with the combined drilling fluid and fracturing fluid surface system of claim 7;
- (b) rotating the drill string in the subterranean wellbore to drill the wellbore;
- (c) changing a position of the multiport valve so as to break hydraulic communication between the drilling fluid sub-system and the drill string and to establish hydraulic communication between the fracturing fluid sub-system and the hydraulic fracturing assembly;
- (d) pumping formation fracturing fluid downhole to the hydraulic fracturing assembly to hydraulically fracture the subterranean formation.
11. A method for hydraulically fracturing a subterranean formation, the method comprising:
- (a) rotating a drill string in a subterranean wellbore to drill the wellbore, the drill string including a drill bit and a hydraulic fracturing assembly;
- (b) hydraulically fracturing the subterranean formation at a plurality of axially spaced locations along the wellbore while tripping the drill string out of the wellbore, wherein hydraulically fracturing the subterranean formation includes (i) translating the drill string in an uphole direction so that a set of frac ports in the hydraulic fracturing assembly is adjacent a region of the formation selected for fracturing, (ii) expanding at least one pair of packers to seal an annular region of the wellbore exterior to the frac ports, and (iii) pumping fracturing fluid downhole through the frac ports to hydraulically fracture the subterranean formation.
12. The method of claim 11 wherein (b) further comprises (iv) repeating (i), (ii), and (iii) at the plurality of axially spaced locations along the wellbore while tripping the drill string out of the wellbore.
13. The method of claim 11, wherein (a) further comprises acquiring and evaluating logging while drilling data to identify a plurality of regions for fracturing the formation.
14. The method of claim 11, wherein the hydraulic fracturing assembly comprises first and second axially spaced sets of frac ports and wherein (b)(iii) comprises pumping the fracturing fluid simultaneously through the first and second axially spaced sets of frac ports to simultaneously hydraulically fracture adjacent regions of the formation.
15. The method claim 11, wherein the hydraulic fracturing assembly comprises first and second axially spaced sets of frac ports and wherein (b)(ii) and (b)(iii) comprise:
- expanding a first pair of packers to seal a first annular region of the wellbore exterior to the first set of frac ports;
- pumping fracturing fluid through the first set of frac ports to hydraulically fracture the formation adjacent the first annular region of the wellbore;
- expanding a second pair of packers to seal a second annular region of the wellbore exterior to the second set of frac ports; and
- pumping fracturing fluid through the second set of frac ports to hydraulically fracture the formation adjacent the second annular region of the wellbore.
16. The method of claim 11, wherein the subterranean wellbore is a lateral wellbore extending from a pilot wellbore and the method further comprises:
- (c) repeating (a) and (b) to drill and hydraulically fracture a second lateral wellbore extending from the pilot wellbore.
17. A method for drilling and hydraulically fracturing a multilateral wellbore system, the method comprising:
- (a) rotating a drill string in a subterranean wellbore to drill a first lateral wellbore from a pilot wellbore, the drill string including a drill bit and a hydraulic fracturing assembly;
- (b) pumping fracturing fluid through frac ports in the hydraulic fracturing assembly to fracture at least a portion of the first lateral wellbore;
- (c) deploying a plug in the first lateral wellbore;
- (d) rotating the drill string in a subterranean wellbore to drill a second lateral wellbore from the pilot wellbore; and
- (e) pumping fracturing fluid through frac ports in the hydraulic fracturing assembly to fracture at least a portion of the second lateral wellbore.
18. The method of claim 17, further comprising:
- (f) rotating the drill string in subterranean wellbore to drill third lateral wellbore from the first lateral wellbore; and
- (g) pumping fracturing fluid through frac ports in the hydraulic fracturing assembly to fracture at least a portion of the third lateral wellbore.
19. A method for hydraulically fracturing a subterranean formation, the method comprising:
- (a) rotating a drill string in a subterranean wellbore to drill the wellbore, the drill string including a drill bit and a hydraulic fracturing assembly;
- (b) reconfiguring a combined drilling fluid and fracturing fluid surface system so as to break hydraulic communication between a drilling fluid sub-system and the drill string and to establish hydraulic communication between a fracturing fluid sub-system and the drill string;
- (c) lifting the drill string off bottom such that a set of frac ports in the hydraulic fracturing assembly is adjacent to a region of the formation to be fractured:
- (d) expanding a pair of packers deployed about the frac ports to seal an annular region of the wellbore adjacent to the frac ports; and
- (e) pumping fracturing fluid downhole through the frac ports to hydraulically fracture the subterranean formation.
20. The method of claim 19, wherein (a) further comprises acquiring and evaluating logging while drilling data to identify a plurality of regions for fracturing the formation.
21. The method of claim 19, wherein (b) further comprises opening the frac ports in the hydraulic fracturing assembly and closing a valve in a through bore of the hydraulic fracturing assembly to break fluid communication between the fracturing fluid surface system and the drill bit.
22. The method of claim 19, further comprising:
- (f) at least partially contracting the packers and lifting the drill string further off bottom such that the set of frac ports is adjacent to another region of the formation to be fractured,
- (g) re-expanding the packers; and
- (h) pumping fracturing fluid downhole through the frac ports to hydraulically fracture the subterranean formation.
23. A method for hydraulically fracturing a subterranean formation, the method comprising:
- (a) rotating a drill string having a drill bit in a subterranean wellbore to drill the wellbore;
- (b) tripping the drill string out of the wellbore and replacing at least the drill bit with a hydraulic fracturing assembly including a pair of packers deployed about a set of frac ports;
- (c) reconfiguring a combined drilling fluid and fracturing fluid surface system so as to break hydraulic communication between a drilling fluid sub-system and the drill string and to establish hydraulic communication between a fracturing fluid sub-system and the drill string;
- (d) tripping the drill string, including the hydraulic fracturing assembly, into the wellbore so that the set of frac ports is adjacent a region of the formation to be fractured;
- (e) expanding the packers to seal an annular region of the wellbore adjacent to the frac ports; and
- (f) pumping fracturing fluid downhole through the frac ports to hydraulically fracture the subterranean formation.
24. The method of claim 23, wherein (a) further comprises evaluating logging while drilling data to identify a plurality of regions for fracturing the formation.
25. The method of claim 23, further comprising:
- (f) at least partially contracting the packers and tripping the drill string towards the surface such that the set of frac ports is adjacent to another region of the formation to be fractured;
- (g) re-expanding the packers; and
- (h) pumping fracturing fluid downhole through the frac ports to hydraulically fracture the subterranean formation.
26. A method for hydraulically fracturing and casing a subterranean formation, the method comprising:
- (a) rotating a drill string in a subterranean wellbore to drill the wellbore, the drill string including a drill bit, a hydraulic fracturing assembly, and a length of casing string;
- (b) reconfiguring a combined drilling fluid and fracturing fluid surface system so as to break hydraulic communication between a drilling fluid sub-system and the drill string and to establish hydraulic communication between a fracturing fluid sub-system and the drill string;
- (c) lifting the drill string off bottom such that a set of frac ports in the hydraulic fracturing assembly is adjacent to a region of the formation to be fractured;
- (d) pumping fracturing fluid downhole through the set of frac ports to hydraulically fracture the subterranean formation; and
- (e) releasing the length of casing string into the fractured subterranean formation.
27. The method of claim 26, wherein the casing string includes perforations and the fracturing fluid is pumped out through the frac ports and the perforations to fracture the subterranean formation.
28. A fracturing while casing and drilling assembly comprising:
- a drill bit deployed at a first axial end of a drill string;
- a hydraulic fracturing assembly coupled with the drill string and including a pair of packers deployed about a set of frac ports, the hydraulic fracturing assembly further including an actuatable valve deployed in a through bore thereof; and
- a length of casing string deployed about a second axial end of the drill string.
29. The assembly of claim 28, wherein the casing string comprises a plurality of axially spaced perforations.
30. The assembly of claim 28, wherein the hydraulic fracturing assembly is deployed internal to the casing string.
31. The assembly of claim 28, further comprising a logging while drilling tool deployed between the drill bit and the casing string.
32. A method for drilling, fracturing, and casing a subterranean formation, the method comprising:
- (a) rotating the fracturing while casing and drilling assembly of claim 28 in a subterranean wellbore to drill the wellbore;
- (b) lifting the drill string off bottom such that a set of frac ports in the hydraulic fracturing assembly is adjacent to a region of the formation to be fractured;
- (c) pumping fracturing fluid downhole through the set frac ports to hydraulically fracture the subterranean formation; and
- (d) releasing the length of casing string into the fractured subterranean formation.
33. A method for drilling, fracturing, and casing a subterranean formation, the method comprising:
- (a) rotating the fracturing while casing and drilling assembly of claim 29 in a subterranean wellbore to drill the wellbore;
- (b) lifting the drill string off bottom such that a first perforation in the casing string is adjacent to a first region of the formation to be fractured and the set of frac ports in the hydraulic fracturing assembly is adjacent to the first perforation;
- (c) pumping fracturing fluid downhole through the set of frac ports to hydraulically fracture the subterranean formation;
- (d) releasing the length of casing string into the fractured subterranean formation and lifting the drill string such that a second perforation in the casing string is adjacent to a second region of the formation to be fractured and the set of frac ports in the hydraulic fracturing assembly is adjacent to the second first perforation; and
- (e) pumping fracturing fluid downhole through the set frac ports to hydraulically fracture the subterranean formation.
Type: Application
Filed: Aug 22, 2014
Publication Date: Feb 25, 2016
Inventors: James Ernest Brown (Sugar Land, TX), Robert J. Utter (Sugar Land, TX), Iain M. Cooper (Sugar Land, TX), Matthew J. Miller (Katy, TX), Dmitriy Ivanovich Potapenko (Sugar Land, TX)
Application Number: 14/466,705