Systems and Methods for Stimulating a Subterranean Formation

Abstract

Systems and methods for stimulating a subterranean formation. The methods may include flowing, with a carrier fluid stream, an autonomous perforation device within a casing conduit that is defined by a casing string that extends within a subterranean formation. The methods further may include retaining the autonomous perforation device within a target region of the casing conduit, flowing a stimulant fluid within the casing conduit and past the autonomous perforation device, and/or stimulating, with the stimulant fluid stream, a portion of the subterranean formation that is downhole from the autonomous perforation device. The systems may include the autonomous perforation device, which may include a perforation assembly, a motion-arresting assembly, and a fluid flow conduit. The systems also may include a hydrocarbon well that includes a wellbore, the casing string, and the autonomous perforation device.

1 . A method of stimulating a subterranean formation, the method comprising:
 flowing, with a carrier fluid stream, an autonomous perforation device within a casing conduit that is defined by a casing string within the subterranean formation;   retaining the autonomous perforation device within a target region of the casing conduit;   subsequent to the retaining, flowing a stimulant fluid stream within the casing conduit and past the autonomous perforation device via a fluid flow conduit that is at least partially defined by the autonomous perforation device; and   stimulating, with the stimulant fluid stream, a portion of the subterranean formation that is downhole from the autonomous perforation device.   
     
     
         2 . The method of  claim 1 , wherein the stimulant fluid stream is a proppant slurry stream, and further wherein the method includes perforating the casing string with the autonomous perforation device responsive to a pressure within the target region of the casing conduit exceeding a threshold screenout pressure. 
     
     
         3 . The method of  claim 1 , wherein the method further includes:
 fluidly isolating the target region of the casing conduit from the subterranean formation; and   perforating the casing string responsive to a pressure within the target region of the casing conduit exceeding a threshold perforating pressure, wherein the perforating includes creating a perforation within the casing string with the autonomous perforation device.   
     
     
         4 . The method of  claim 3 , wherein the fluidly isolating includes at least one of:
 (i) locating a ball sealer on a ball sealer seat that is defined by the autonomous perforation device to restrict flow of the stimulant fluid stream past the autonomous perforation device;   (ii) flowing the ball sealer through the fluid flow conduit and locating the ball sealer on an existing perforation that is downhole from the autonomous perforation device; and   (iii) closing a valve that forms a portion of the autonomous perforation device to restrict flow of the stimulant fluid stream past the autonomous perforation device.   
     
     
         5 . The method of  claim 3 , wherein the perforating further includes releasing a sealing material into the casing conduit, wherein the releasing includes at least one of:
 (i) releasing at least one ball sealer from the autonomous perforation device;   (ii) releasing a supplemental sealing material from the autonomous perforation device; and   (iii) breaking apart the autonomous perforation device to form the sealing material.   
     
     
         6 . The method of  claim 1 , wherein the autonomous perforation device is a first autonomous perforation device, wherein the target region of the casing conduit is a first target region of the casing conduit, wherein the fluid flow conduit is a first fluid flow conduit, wherein the portion of the subterranean formation is a first portion of the subterranean formation, and further wherein the method includes:
 flowing, with the carrier fluid stream, a second autonomous perforation device within the casing conduit;   retaining the second autonomous perforation device within a second target region of the casing conduit, wherein the second target region is uphole from the first target region;   flowing the stimulant fluid stream past the second autonomous perforation device via a second fluid flow conduit that is at least partially defined by the second autonomous perforation device; and   stimulating, with the stimulant fluid stream, a second portion of the subterranean formation that is downhole from the second autonomous perforation device.   
     
     
         7 . The method of  claim 1 , wherein the retaining includes expanding the autonomous perforation device from a retracted configuration to an expanded configuration. 
     
     
         8 . The method of  claim 1 , wherein the retaining includes retaining with a motion-arresting assembly that forms a portion of the autonomous perforation device, and further wherein the retaining includes at least one of:
 (i) operatively engaging at least a portion of the motion-arresting assembly with a projection that extends within the casing conduit; and   (ii) operatively engaging the motion-arresting assembly with the casing string.   
     
     
         9 . The method of  claim 1 , wherein the stimulant fluid stream is the carrier fluid stream. 
     
     
         10 . The method of  claim 1 , wherein the stimulant fluid stream is different from the carrier fluid stream. 
     
     
         11 . The method of  claim 10 , wherein the stimulant fluid stream includes particulate material and the carrier fluid stream is at least substantially free of particulate material. 
     
     
         12 . An autonomous perforation device configured to be flowed within a casing conduit that is defined by a casing string within a subterranean formation, the autonomous perforation device comprising:
 a perforation assembly;   a motion-arresting assembly configured to be selectively actuated to retain the autonomous perforation device within a target region of the casing conduit; and   a fluid flow conduit defined at least in part by the autonomous perforation device, wherein the fluid flow conduit permits fluid flow between a portion of the casing conduit that is uphole from the autonomous perforation device and a portion of the casing conduit that is downhole from the autonomous perforation device when the autonomous perforation device is retained within the target region of the casing conduit.   
     
     
         13 . The device of  claim 12 , wherein the perforation assembly includes a perforation gun that includes at least one perforation charge. 
     
     
         14 . The device of  claim 12 , wherein the perforation assembly is an autonomous perforation assembly configured to autonomously create a perforation within the casing string responsive to a wellbore pressure within the casing conduit proximal to the autonomous perforation device exceeding a threshold perforating pressure. 
     
     
         15 . The device of  claim 12 , wherein the perforation assembly is configured to create a perforation within the casing string responsive to receipt of a perforation signal. 
     
     
         16 . The device of  claim 12 , wherein the motion-arresting assembly defines a retracted configuration, in which the motion-arresting assembly permits the autonomous perforation device to flow within the casing conduit, and an expanded configuration, in which the motion-arresting assembly restricts motion of the autonomous perforation device within the casing conduit, and further wherein the motion-arresting assembly is configured to be selectively transitioned from the retracted configuration to the expanded configuration to retain the autonomous perforation device within the target region of the casing conduit. 
     
     
         17 . The device of  claim 12 , wherein the motion-arresting assembly is an autonomous motion-arresting assembly configured to autonomously retain the autonomous perforation device within the target region of the casing conduit responsive to a retention criterion. 
     
     
         18 . The device of  claim 17 , wherein the retention criterion includes at least one of:
 (i) a pressure within the casing conduit proximal to the autonomous perforation device exceeding a threshold retention pressure;   (ii) the autonomous perforation device being present within the target region of the casing conduit;   (iii) the autonomous perforation device flowing along a target length of the casing conduit; and   (iv) the autonomous perforation device flowing through a target number of casing collars.   
     
     
         19 . The device of  claim 12 , wherein the motion-arresting assembly is configured to retain the autonomous perforation device within the target region of the casing conduit responsive to receipt of a retention signal. 
     
     
         20 . The device of  claim 12 , wherein the autonomous perforation device includes a plurality of fluid flow conduits that each permits a respective fluid flow between the portion of the casing conduit that is uphole from the autonomous perforation device and the portion of the casing conduit that is downhole from the autonomous perforation device. 
     
     
         21 . The device of  claim 12 , wherein the autonomous perforation device includes a plurality of fins that at least partially define the fluid flow conduit. 
     
     
         22 . The device of  claim 12 , wherein the autonomous perforation device further includes a fluid flow conduit sealing assembly that is configured to selectively restrict fluid flow through the fluid flow conduit. 
     
     
         23 . The device of  claim 22 , wherein the fluid flow conduit sealing assembly includes a valve that is configured to selectively transition between an open configuration, in which the valve permits the fluid flow through the fluid flow conduit, and a closed configuration, in which the valve restricts the fluid flow through the fluid flow conduit. 
     
     
         24 . The device of  claim 22 , wherein the fluid flow conduit sealing assembly includes a ball sealer seat that is defined by the autonomous perforation device and that is configured to selectively restrict the fluid flow through the fluid flow conduit responsive to receipt of a ball sealer. 
     
     
         25 . The device of  claim 12 , wherein the autonomous perforation device includes a storage structure that is configured to selectively release a sealing material. 
     
     
         26 . The device of  claim 12 , wherein the autonomous perforation device further includes an autonomous control assembly that is configured to autonomously control the operation of at least a portion of the autonomous perforation device. 
     
     
         27 . The device of  claim 26 , wherein the autonomous control assembly is configured to at least one of:
 (i) actuate the perforation assembly;   (ii) actuate the motion-arresting assembly; and   (iii) selectively restrict the fluid flow through the fluid flow conduit.   
     
     
         28 . A hydrocarbon well, comprising:
 the autonomous perforation device of  claim 12 ;   a wellbore that extends within the subterranean formation; and   a casing string, wherein the casing string extends within the wellbore, and further wherein the autonomous perforation device is located within the casing conduit.   
     
     
         29 . The hydrocarbon well of  claim 28 , wherein the casing conduit further includes a plurality of projections that extend within the casing conduit to define a plurality of reduced-area regions of the casing conduit, and further wherein the motion-arresting assembly is operatively engaged with a selected one of the plurality of projections.