Methods and systems for characterizing fractures in a subterranean formation are provided. The method includes introducing an encapsulated explosive unit into a casing located in a wellbore within the subterranean formation and maintaining the encapsulated explosive unit in a stage of the casing. The method also includes detonating the encapsulated explosive unit within the stage to generate a pressure wave that passes through a group of perforations and into the fractures and measuring a reflected pressure wave using a pressure sensor coupled to the bridge plug to produce a pressure measurement. The method further includes converting the pressure measurement into an acoustic signal correlated with the pressure measurement by an acoustic signal generator contained in the bridge plug and transmitting the acoustic signal to apply acoustic pressure on a fiber optic cable coupled to an exterior surface of the casing.

The method comprises providing at least one seismic source in a seismic source area and providing a plurality of seismic receivers in said seismic source area, said method comprising measuring a first type of ground vibrations induced in a subsurface of the area of interest by the at least one seismic source with the plurality of seismic receivers. The method further comprises measuring with the plurality of seismic receivers at least one second type of ground vibrations induced by a mechanical source different from the or from each seismic source and analyzing the second type of ground vibrations to determine at least one information among: a physical parameter of the subsurface and/or, a presence of human and/or an animal and/or a vehicle.

The method comprises providing at least one seismic source in a seismic source area and providing a plurality of seismic receivers in said seismic source area, said method comprising measuring a first type of ground vibrations induced in a subsurface of the area of interest by the at least one seismic source with the plurality of seismic receivers. The method further comprises measuring with the plurality of seismic receivers at least one second type of ground vibrations induced by a mechanical source different from the or from each seismic source and analyzing the second type of ground vibrations to determine at least one information among: a physical parameter of the subsurface and/or, a presence of human and/or an animal and/or a vehicle.

The present technology is essentially a portable seismic survey system and method using reflection seismology for mapping subterranean formations. The device includes an upper assembly, a firing pin operably associated with a firing pin actuator, a lower assembly including a cartridge holder capable of retaining a blasting cartridge, and a detonation sensor capable of detecting detonation of the blasting cartridge. The system can further include an anchoring assembly, and an adjustable shield assembly. The detonation sensor transmits a signal to an event marking device to trigger a recordation of detonation time and geographic location of the seismic survey device. A seismic wave is generated upon detonation, which is then reflected back toward seismometers. Data from the event marking system and seismometers can then be processed to provide geological formation information.

The present technology is essentially a portable seismic survey system and method using reflection seismology for mapping subterranean formations. The device includes an upper assembly, a firing pin operably associated with a firing pin actuator, a lower assembly including a cartridge holder capable of retaining a blasting cartridge, and a detonation sensor capable of detecting detonation of the blasting cartridge. The system can further include an anchoring assembly, and an adjustable shield assembly. The detonation sensor transmits a signal to an event marking device to trigger a recordation of detonation time and geographic location of the seismic survey device. A seismic wave is generated upon detonation, which is then reflected back toward seismometers. Data from the event marking system and seismometers can then be processed to provide geological formation information.

Downhole tools and methods for detecting a downhole obstruction within a wellbore. The downhole tools include a positioning mechanism, which is configured to facilitate positioning of the downhole tool within a target region of a wellbore of a hydrocarbon well, an acoustic pulse generator, which is configured to generate an acoustic pulse within a wellbore liquid that extends within the wellbore and fluidly contacts the downhole tool, and a sensor assembly, which is configured to detect a reflected acoustic pulse within the wellbore liquid. The methods include positioning a downhole tool within a target region of a wellbore, generating an acoustic pulse, propagating the acoustic pulse within a wellbore liquid, and reflecting the acoustic pulse from a downhole obstruction. The methods also include propagating a reflected acoustic pulse within the wellbore liquid, receiving the reflected acoustic pulse, and characterizing the downhole obstruction based upon the reflected acoustic pulse.

Downhole tools and methods for detecting a downhole obstruction within a wellbore. The downhole tools include a positioning mechanism, which is configured to facilitate positioning of the downhole tool within a target region of a wellbore of a hydrocarbon well, an acoustic pulse generator, which is configured to generate an acoustic pulse within a wellbore liquid that extends within the wellbore and fluidly contacts the downhole tool, and a sensor assembly, which is configured to detect a reflected acoustic pulse within the wellbore liquid. The methods include positioning a downhole tool within a target region of a wellbore, generating an acoustic pulse, propagating the acoustic pulse within a wellbore liquid, and reflecting the acoustic pulse from a downhole obstruction. The methods also include propagating a reflected acoustic pulse within the wellbore liquid, receiving the reflected acoustic pulse, and characterizing the downhole obstruction based upon the reflected acoustic pulse.

Methods for using a single explosive material whose specific volume energy can be controlled for use in at least a segment of a borehole. Alternatively, or additionally, methods for using mixtures of one or more explosive materials and one or more non-explosive energetic materials whose specific volume energy can be controlled for use in at least a segment of a borehole. Such methods include determining a target specific volume energy required for the explosive/energetic materials in the segment of the borehole and selecting a product mixture for that segment of the borehole which will produce the required target energy.

Simulation of downhole transient pressure effects due to propellant stimulation of a formation provides information that may be utilized to select a type of perforating tool system and other components that contribute to effective stimulation of a formation. A well simulator pressure vessel comprises a perforating tool system that comprises a type of perforating gun assembly that includes one or more shaped charges. A propellant disk assembly adjacent to a sample formation is coupled to the perforating tool system. The propellant disk assembly comprises one or more components for securing the propellant. A transient pressure effect may be measured once the one or more shaped charges are detonated and the propellant is ignited or deflagrated. The measured transient pressure effects may be utilized to alter or change the one or more components of the perforating tool system prior to, during, or after stimulation of the sample formation.

Simulation of downhole transient pressure effects due to propellant stimulation of a formation provides information that may be utilized to select a type of perforating tool system and other components that contribute to effective stimulation of a formation. A well simulator pressure vessel comprises a perforating tool system that comprises a type of perforating gun assembly that includes one or more shaped charges. A propellant disk assembly adjacent to a sample formation is coupled to the perforating tool system. The propellant disk assembly comprises one or more components for securing the propellant. A transient pressure effect may be measured once the one or more shaped charges are detonated and the propellant is ignited or deflagrated. The measured transient pressure effects may be utilized to alter or change the one or more components of the perforating tool system prior to, during, or after stimulation of the sample formation.