Determining in-situ rock stress

A downhole tool system, comprising:

• a downhole tool comprising:
• a housing configured to couple to a downhole conveyance, at least a portion of the housing comprising a perforated section;
• at least one expandable member positioned within the perforated section of the housing;
• one or more protrusions coupled with at least one expandable member through one or more adjustable shape members, the one or more adjustable shape members comprising memory metal;
• and
• one or more acoustic receivers positioned in the housing;
• and
• a control system communicably coupled to the downhole tool and configured to perform operations comprising:
• actuating the downhole tool, at a location in the wellbore adjacent an underground rock formation, to adjust the at least one expandable member to move the one or more protrusions into or near contact with the underground rock formation;
• activating the one or more adjustable shape members to move the one or more protrusions to fracture the underground rock formation with the one or more protrusions through forcible contact between the one or more protrusions and the underground rock formation;
• determining a wellbore pressure increase at the location in the wellbore based on the fracture;
• determining one or more properties of the underground rock formation based at least in part on the determined wellbore pressure increase;
• controlling the one or more acoustic receivers to receive one or more acoustic signals at the downhole tool, the one or more acoustic signals caused by the fracture;
• and
• determining at least one azimuth angle of one or more far-field stresses based on the one or more acoustic signals.

A method for determining one or more rock properties, comprising:

• running a downhole tool into a wellbore formed from a terranean surface to a subterranean zone that comprises an underground rock formation, the downhole tool comprising one or more protrusions coupled with at least one expandable member by one or more adjustable shape members of the downhole tool, the one or more adjustable shape members comprising memory metal;
• actuating the downhole tool, at a location in the wellbore adjacent the underground rock formation, to adjust the at least one expandable member to move the one or more protrusions into or near contact with the underground rock formation;
• activating the one or more adjustable shape members to move the one or more protrusions to fracture the underground rock formation through forcible contact between the one or more protrusions and the underground rock formation;
• determining a wellbore pressure increase at the location in the wellbore based on the fracture;
• determining one or more properties of the underground rock formation based at least in part on the determined wellbore pressure increase;
• de-activating the one or more adjustable shape members to cease the forcible contact between the one or more protrusions and the underground rock formation;
• rotating the at least one expandable member;
• re-activating the one or more adjustable shape members to move the one or more protrusions to fracture the underground rock formation through forcible contact between the one or more protrusions and the underground rock formation;
• and
• determining another wellbore pressure increase at the location in the wellbore based on the fracture.

A method for determining one or more rock properties, comprising:

• running a downhole tool into a wellbore formed from a terranean surface to a subterranean zone that comprises an underground rock formation, the downhole tool comprising one or more protrusions coupled with at least one expandable member by one or more adjustable shape members of the downhole tool, the one or more adjustable shape members comprising memory metal;
• actuating the downhole tool, at a location in the wellbore adjacent the underground rock formation, to adjust the at least one expandable member to move the one or more protrusions into or near contact with the underground rock formation;
• prior to actuating the downhole tool:
• actuating a first wellbore seal of the downhole tool at an uphole end of the location in the wellbore;
• actuating a second wellbore seal of the downhole tool at a downhole end of the location in the wellbore;
• and
• based on the actuation of the first and second wellbore seals, fluidly isolating a volume of the wellbore at the location adjacent the underground rock formation from respective volumes of the wellbore uphole of the first wellbore seal and downhole of the second wellbore seal;
• prior to actuating the downhole tool and subsequent to fluidly isolating the volume of the wellbore at the location adjacent the underground rock formation, determining a static or flowing bottom hole pressure of the wellbore at the location adjacent the underground rock formation;
• activating the one or more adjustable shape members to move the one or more protrusions to fracture the underground rock formation by the one or more protrusions through forcible contact between the one or more protrusions and the underground rock formation;
• subsequent to the fracture, through contacting engagement of the one or more protrusions with the underground rock formation, determining a wellbore pressure at the location in the wellbore;
• determining a wellbore pressure increase at the location in the wellbore based on the fracture;
• determining the wellbore pressure increase at the location in the wellbore based on a difference between the static or flowing bottom hole pressure and the wellbore pressure at the location in the wellbore;
• and
• determining one or more properties of the underground rock formation based at least in part on the determined wellbore pressure increase.

A method for determining one or more rock properties, comprising:

• running a downhole tool into a wellbore formed from a terranean surface to a subterranean zone that comprises an underground rock formation, the downhole tool comprising one or more protrusions coupled with at least one expandable member by one or more adjustable shape members of the downhole tool, the one or more adjustable shape members comprising memory metal;
• actuating the downhole tool, at a location in the wellbore adjacent the underground rock formation, to adjust the at least one expandable member to move the one or more protrusions into or near contact with the underground rock formation, where actuating the downhole tool to adjust the at least one expandable member comprises at least one of:
• shifting a wedge into contact with the at least one expandable member to radially move the at least one expandable member away from a radial centerline of the downhole tool;
• or
• fluidly expanding a bladder positioned to contact the at least one expandable member to radially move the at least one expandable member away from a radial centerline of the downhole tool;
• activating the one or more adjustable shape members to move the one or more protrusions to fracture the underground rock formation by the one or more protrusions through forcible contact between the one or more protrusions and the underground rock formation;
• determining a wellbore pressure increase at the location in the wellbore based on the fracture;
• and
• determining one or more properties of the underground rock formation based at least in part on the determined wellbore pressure increase.

A downhole tool system, comprising:

• a downhole tool comprising:
• a housing configured to couple to a downhole conveyance, at least a portion of the housing comprising a perforated section;
• at least one expandable member positioned within the perforated section of the housing;
• one or more protrusions coupled with at least one expandable member through one or more adjustable shape members, the one or more adjustable shape members comprising memory metal;
• and
• a pressure monitoring sub-assembly mounted in the housing positioned to receive a wellbore fluid flow from the underground rock formation through the perforated section of the housing;
• a first wellbore seal positioned on the tool uphole of the at least one expandable member and the one or more protrusions;
• a second wellbore seal positioned on the tool downhole of the at least one expandable member and the one or more protrusions;
• and
• a control system communicably coupled to the downhole tool and configured to perform operations comprising:
• actuating the first wellbore seal of the downhole tool at an uphole end of the location in the wellbore;
• actuating the second wellbore seal of the downhole tool at a downhole end of the location in the wellbore to fluidly isolate a volume of the wellbore at the location adjacent the underground rock formation from respective volumes of the wellbore uphole of the first wellbore seal and downhole of the second wellbore seal;
• actuating the downhole tool, at a location in the wellbore adjacent an underground rock formation, to adjust the at least one expandable member to move the one or more protrusions into or near contact with the underground rock formation;
• prior to actuating the downhole tool and subsequent to fluidly isolating the volume of the wellbore at the location adjacent the underground rock formation, controlling the pressure monitoring sub-assembly to determine a static or flowing bottom hole pressure of the wellbore at the location adjacent the underground rock formation;
• activating the one or more adjustable shape members to move the one or more protrusions to fracture the underground rock formation with the one or more protrusions through forcible contact between the one or more protrusions and the underground rock formation;
• subsequent to the fracture, through contacting engagement of the one or more protrusions with the underground rock formation, controlling the pressure monitoring sub-assembly to determine a wellbore pressure at the location in the wellbore;
• determining the wellbore pressure increase at the location in the wellbore based on a difference between the static or flowing bottom hole pressure and the wellbore pressure at the location in the wellbore;
• determining a wellbore pressure increase at the location in the wellbore based on the fracture;
• and
• determining one or more properties of the underground rock formation based at least in part on the determined wellbore pressure increase.

A downhole tool system, comprising:

• a downhole tool comprising:
• a housing configured to couple to a downhole conveyance, at least a portion of the housing comprising a perforated section;
• at least one expandable member positioned within the perforated section of the housing;
• and
• one or more protrusions coupled with at least one expandable member through one or more adjustable shape members, the one or more adjustable shape members comprising memory metal;
• and
• a control system communicably coupled to the downhole tool and configured to perform operations comprising:
• actuating the downhole tool, at a location in the wellbore adjacent an underground rock formation, to adjust the at least one expandable member to move the one or more protrusions into or near contact with the underground rock formation, where the operation of actuating the downhole tool to adjust the at least one expandable member comprises at least one of:
• shifting, in response to a command from the control system, a wedge into contact with the at least one expandable member to radially move the at least one expandable member away from a radial centerline of the downhole tool;
• or
• fluidly expanding, in response to a command from the control system, a bladder positioned to contact the at least one expandable member to radially move the at least one expandable member away from a radial centerline of the downhole tool;
• activating the one or more adjustable shape members to move the one or more protrusions to fracture the underground rock formation with the one or more protrusions through forcible contact between the one or more protrusions and the underground rock formation;
• determining a wellbore pressure increase at the location in the wellbore based on the fracture;
• and
• determining one or more properties of the underground rock formation based at least in part on the determined wellbore pressure increase.

A downhole tool system, comprising:

• a downhole tool comprising:
• a housing configured to couple to a downhole conveyance, at least a portion of the housing comprising a perforated section;
• at least one expandable member positioned within the perforated section of the housing;
• one or more protrusions coupled with at least one expandable member through one or more adjustable shape members, the one or more adjustable shape members comprising memory metal;
• a pressure monitoring sub-assembly mounted in the housing positioned to receive a wellbore fluid flow from the underground rock formation through the perforated section of the housing;
• and
• a rotating sub-assembly coupled to the at least one expandable member;
• a first wellbore seal positioned on the tool uphole of the at least one expandable member and the one or more protrusions;
• a second wellbore seal positioned on the tool downhole of the at least one expandable member and the one or more protrusions;
• and
• a control system communicably coupled to the downhole tool and configured to perform operations comprising:
• actuating the first wellbore seal of the downhole tool at an uphole end of the location in the wellbore;
• actuating the second wellbore seal of the downhole tool at a downhole end of the location in the wellbore to fluidly isolate a volume of the wellbore at the location adjacent the underground rock formation from respective volumes of the wellbore uphole of the first wellbore seal and downhole of the second wellbore seal;
• actuating the downhole tool, at a location in the wellbore adjacent an underground rock formation, to adjust the at least one expandable member to move the one or more protrusions into or near contact with the underground rock formation;
• prior to actuating the downhole tool and subsequent to fluidly isolating the volume of the wellbore at the location adjacent the underground rock formation, controlling the pressure monitoring sub-assembly to determine a static or flowing bottom hole pressure of the wellbore at the location adjacent the underground rock formation;
• activating the one or more adjustable shape members to move the one or more protrusions to fracture the underground rock formation with the one or more protrusions through forcible contact between the one or more protrusions and the underground rock formation;
• determining a wellbore pressure increase at the location in the wellbore based on the fracture;
• determining one or more properties of the underground rock formation based at least in part on the determined wellbore pressure increase;
• de-activating the one or more adjustable shape members to cease the forcible contact between the one or more protrusions and the underground rock formation;
• controlling the rotating sub-assembly to rotate the at least one expandable member;
• re-activating the one or more adjustable shape members to move the one or more protrusions to fracture the underground rock formation through forcible contact between the one or more protrusions and the underground rock formation;
• and
• controlling the pressure monitoring system to determine another wellbore pressure increase at the location in the wellbore based on the fracture.