Improved methods of providing acoustic source signals for seismic surveying, wherein a plurality of signals can be easily separated from one another after data acquisition, wherein the source signals are not sweep based.

Extracting a core sample from within a wellbore is optimized based on information extracted from acoustic signals that are generated downhole. The acoustic signals provide an indication of the formation being cored, which is used to obtain or adjust designated coring operating parameters for accomplishing an efficient and effective coring procedure. Coring operating parameters that are adjusted include weight on bit and bit rotational speed. Optimizing coring operating parameters reduces wear on the bit and produces samples with less fractures. Generating acoustic signals is done by the operation of coring itself, or contacting the formation with a coring bit. Contacting includes impacting the coring bit radially against the wellbore's sidewall, or moving the bit laterally after coring operations have initiated.

Extracting a core sample from within a wellbore is optimized based on information extracted from acoustic signals that are generated downhole. The acoustic signals provide an indication of the formation being cored, which is used to obtain or adjust designated coring operating parameters for accomplishing an efficient and effective coring procedure. Coring operating parameters that are adjusted include weight on bit and bit rotational speed. Optimizing coring operating parameters reduces wear on the bit and produces samples with less fractures. Generating acoustic signals is done by the operation of coring itself, or contacting the formation with a coring bit. Contacting includes impacting the coring bit radially against the wellbore's sidewall, or moving the bit laterally after coring operations have initiated.

A method for mapping acoustic properties of water bottom sediments includes penetrating a piling into the water bottom sediments at a first of a plurality of locations. A first distributed acoustic sensor is inserted adjacent to the first piling. A second piling is driven into sediments at a second location. Acoustic signals are detected at the first acoustic sensor while penetrating the second piling. The detecting is indexed to a depth of the second piling as it is driven. A second acoustic sensor is inserted adjacent to the second piling. Penetrating a piling, detecting acoustic signals at each acoustic sensor and inserting a sensor are repeated until a piling is driven at all the locations. The signals are used to generate a map of properties of the sediments bounded by the plurality of locations. The properties comprise attenuation excluding effects of diffractors in the sediments.

A method for mapping acoustic properties of water bottom sediments includes penetrating a piling into the water bottom sediments at a first of a plurality of locations. A first distributed acoustic sensor is inserted adjacent to the first piling. A second piling is driven into sediments at a second location. Acoustic signals are detected at the first acoustic sensor while penetrating the second piling. The detecting is indexed to a depth of the second piling as it is driven. A second acoustic sensor is inserted adjacent to the second piling. Penetrating a piling, detecting acoustic signals at each acoustic sensor and inserting a sensor are repeated until a piling is driven at all the locations. The signals are used to generate a map of properties of the sediments bounded by the plurality of locations. The properties comprise attenuation excluding effects of diffractors in the sediments.

Systems and methods for deploying and using a controlled-frequency downhole seismic source are provided. A downhole seismic source may be placed into a borehole in a geological formation and coupled rigidly to the geological formation via an edge of the borehole. A controlled-frequency seismic signal may be generated sufficient to enable a seismic measurement of the geological formation.

A source of acoustic energy for a downhole environment can include a motor and a mechanical energy storage device. The mechanical energy storage device may be for storing a preset amount of torque generated by the motor. The source can also include a rigid body moveable between a retracted position and an extended position by the mechanical energy storage device. The rigid body may be for releasing the acoustic energy into the downhole environment in response to the mechanical energy storage device releasing the preset amount of torque generated by the motor and moving the rigid body to the extended position.

A source of acoustic energy for a downhole environment can include a motor and a mechanical energy storage device. The mechanical energy storage device may be for storing a preset amount of torque generated by the motor. The source can also include a rigid body moveable between a retracted position and an extended position by the mechanical energy storage device. The rigid body may be for releasing the acoustic energy into the downhole environment in response to the mechanical energy storage device releasing the preset amount of torque generated by the motor and moving the rigid body to the extended position.

Provided is an exploration system comprising a plurality of vibration generating vehicles, wherein resource exploration is performed by a vibration generating action by a group of vibration generating vehicles constituted by the plurality of vibration generating vehicles, each of the plurality of vibration generating vehicles of the group of vibration generating vehicles is provided with: a storage unit in which vibration location information related to a vibration location in a vibration by the group of vibration generating vehicles is stored in association with the group of vibration generating vehicles; an exploration unit that performs a vibration generating action for exploration; a control unit that controls movement of the vibration generating vehicle; and a calculation unit that obtains location information from the storage unit, instructs movement to the control unit on the basis of the obtained location information and instructs a vibration generating action to the exploration unit after the movement.

Apparatus for generating shear waves usable in determining shear waves usable in determining distribution and orientation of geologic features in the subsurface among other uses, having a hammer bar with a rod connected to a center position of the hammer bar and having a coil spring therewith and two magnets on each side of the rod to hold the hammer bar in a position to strike the anvil bar.