Detonation control modules and detonation control circuits are provided herein. A trigger input signal can cause a detonation control module to trigger a detonator. A detonation control module can include a timing circuit, a light-producing diode such as a laser diode, an optically triggered diode, and a high-voltage capacitor. The trigger input signal can activate the timing circuit. The timing circuit can control activation of the light-producing diode. Activation of the light-producing diode illuminates and activates the optically triggered diode. The optically triggered diode can be coupled between the high-voltage capacitor and the detonator. Activation of the optically triggered diode causes a power pulse to be released from the high-voltage capacitor that triggers the detonator.

Detonation control modules and detonation control circuits are provided herein. A trigger input signal can cause a detonation control module to trigger a detonator. A detonation control module can include a timing circuit, a light-producing diode such as a laser diode, an optically triggered diode, and a high-voltage capacitor. The trigger input signal can activate the timing circuit. The timing circuit can control activation of the light-producing diode. Activation of the light-producing diode illuminates and activates the optically triggered diode. The optically triggered diode can be coupled between the high-voltage capacitor and the detonator. Activation of the optically triggered diode causes a power pulse to be released from the high-voltage capacitor that triggers the detonator.

Examples of a pressure wave generator configured to generate high energy pressure waves in a medium are disclosed. The pressure wave generator can include a sabot carrying a piston. The sabot can further comprise a locking means to lock the piston in a fixed position when the locking means are activated. When the locking means are in a deactivated position, the piston can be released and can move at least partially away from the sabot. The sabot carrying the piston can be disposed within an inner bore of a housing of the pressure wave generator and can move within the inner bore of the housing from its first end toward its second end along a longitudinal axis of the bore. A transducer can be accommodated in the second end of the housing. The transducer can be coupled to the medium and can convert a portion of the kinetic energy of the piston into a pressure wave in the medium upon impact of the piston with the transducer. The sabot carrying the piston can be accelerated by applying a motive force to the sabot. Once accelerated within the inner bore of the housing the sabot can be decelerated by applying a restraining force to the sabot while the piston can be released at least partially from the sabot to continue to move toward the transducer until it impacts the transducer. Examples of methods of operating the pressure wave generator are disclosed.

Examples of a pressure wave generator configured to generate high energy pressure waves in a medium are disclosed. The pressure wave generator can include a sabot carrying a piston. The sabot can further comprise a locking means to lock the piston in a fixed position when the locking means are activated. When the locking means are in a deactivated position, the piston can be released and can move at least partially away from the sabot. The sabot carrying the piston can be disposed within an inner bore of a housing of the pressure wave generator and can move within the inner bore of the housing from its first end toward its second end along a longitudinal axis of the bore. A transducer can be accommodated in the second end of the housing. The transducer can be coupled to the medium and can convert a portion of the kinetic energy of the piston into a pressure wave in the medium upon impact of the piston with the transducer. The sabot carrying the piston can be accelerated by applying a motive force to the sabot. Once accelerated within the inner bore of the housing the sabot can be decelerated by applying a restraining force to the sabot while the piston can be released at least partially from the sabot to continue to move toward the transducer until it impacts the transducer. Examples of methods of operating the pressure wave generator are disclosed.

Seismic blasting methods and apparatus are presented in which detonator confirmation time break (CTB) is accurately determined by maintaining an applied voltage across detonator leg wires following initiation of a firing command or signal and sensing one or more electrical parameters such as voltage and/or current, and selectively identifying a CTB representing a time at which the monitored electrical parameter indicates a successful detonation.

Seismic blasting methods and apparatus are presented in which detonator confirmation time break (CTB) is accurately determined by maintaining an applied voltage across detonator leg wires following initiation of a firing command or signal and sensing one or more electrical parameters such as voltage and/or current, and selectively identifying a CTB representing a time at which the monitored electrical parameter indicates a successful detonation.

A method of mapping micro-fractures of a fracture network comprising: introducing a capsule or coated capsule or containment into the fracture network, where in the capsules or containment comprise an explosive substance and a plurality of micro-proppant; allowing initiation of the explosive substance of some or all of the plurality of the capsules to occur, wherein initiation of the explosive substance causes detonation of the explosive substance, and wherein the detonation produces one or more micro-seismic events; and causing or allowing at least a portion of the micro-proppant to enter one or more of the micro-fractures.

A method of mapping micro-fractures of a fracture network comprising: introducing a capsule or coated capsule or containment into the fracture network, where in the capsules or containment comprise an explosive substance and a plurality of micro-proppant; allowing initiation of the explosive substance of some or all of the plurality of the capsules to occur, wherein initiation of the explosive substance causes detonation of the explosive substance, and wherein the detonation produces one or more micro-seismic events; and causing or allowing at least a portion of the micro-proppant to enter one or more of the micro-fractures.

An explosive system for fracturing an underground geologic formation adjacent to a wellbore can comprise a plurality of explosive units comprising an explosive material contained within the casing, and detonation control modules electrically coupled to the plurality of explosive units and configured to cause a power pulse to be transmitted to at least one detonator of at least one of the plurality of explosive units for detonation of the explosive material. The explosive units are configured to be positioned within a wellbore in spaced apart positions relative to one another along a string with the detonation control modules positioned adjacent to the plurality of explosive units in the wellbore, such that the axial positions of the explosive units relative to the wellbore are at least partially based on geologic properties of the geologic formation adjacent the wellbore.

An explosive system for fracturing an underground geologic formation adjacent to a wellbore can comprise a plurality of explosive units comprising an explosive material contained within the casing, and detonation control modules electrically coupled to the plurality of explosive units and configured to cause a power pulse to be transmitted to at least one detonator of at least one of the plurality of explosive units for detonation of the explosive material. The explosive units are configured to be positioned within a wellbore in spaced apart positions relative to one another along a string with the detonation control modules positioned adjacent to the plurality of explosive units in the wellbore, such that the axial positions of the explosive units relative to the wellbore are at least partially based on geologic properties of the geologic formation adjacent the wellbore.