Deployable smart acoustic resonance particles have dense cores, compliant matrixes surrounding the cores and stiff outer shells surrounding the matrixes. The particles have mechanical stress sensitivities that provide unique band gap shifts when compressed. Groups of similar particles with similar stress sensitivities and similar band gap shifts are added at different times to hydraulic fluids, as circulated through wells with the fluid and pushed into fractures. A plural, sonic monopole well logging tool is lowered into the well to determine locations and depth of fractures and local pressures by distinct resonance of individual groups.

A system, a method and an autonomous network for vibration monitoring, the system comprising a master station preset for recording vibrations at a master trigger threshold; a secondary station, the secondary station and the master station being time synchronized, a server in communication with the master and secondary stations; wherein, the master station is configured to transmit a master trig time to the server and to start recording vibrations when the master trigger threshold is exceeded; the server is configured to store the master trig time; the secondary station is configured to detect the master trig time stored by the server, and upon detecting the master trig time, to record vibrations; and wherein the master and secondary stations are configured to transmit respective recorded vibrations to the server and the server is configured to classify the recorded vibrations in relation to a preset seismic threshold.

A method for generating a seismic image representing a subsurface includes receiving seismic data for the subsurface formation, including receiver wavelet data and source wavelet data. Source wavefield data are generated based on a forward modeling of the source wavelet data. Receiver wavefield data are generated that compensate for distortions in the seismic data by: applying a dispersion-only model to the receiver wavelet data to generate a first reconstructed back-propagated receiver wavefield portion, applying a dissipation-only model to the receiver wavelet data to generate a second reconstructed back-propagated receiver wavefield portion, and combining the first back-propagated receiver wavefield portion and the second back-propagated receiver wavefield portion into the receiver wavefield data. The method includes applying an imaging condition to the receiver wavefield data and the source wavefield data and generating, based on applying the imaging condition, visco-acoustic reverse time migration (VARTM) result data.

The present invention provides a method and device for determining an excitation point of a seismic source. The method includes: determining, according to a selected medium type, a distribution region corresponding to the selected medium type in a three-dimensional surface model corresponding to a preset surface range, where a preset position of the excitation point of the seismic source is located in the preset surface range, and a first mapping position corresponding to the preset position of the excitation point of the seismic source is located in the three-dimensional surface model; determining a second mapping position in the three-dimensional surface model according to the first mapping position and the determined distribution region; and determining, according to the second mapping position, a target position of the excitation point of the seismic source corresponding to the second mapping position in the preset surface range.

A method for generating a seismic image representing a subsurface includes receiving seismic data for the subsurface formation, including receiver wavelet data and source wavelet data. Source wavefield data are generated based on a forward modeling of the source wavelet data. Receiver wavefield data are generated that compensate for distortions in the seismic data by: applying a dispersion-only model to the receiver wavelet data to generate a first reconstructed back-propagated receiver wavefield portion, applying a dissipation-only model to the receiver wavelet data to generate a second reconstructed back-propagated receiver wavefield portion, and combining the first back-propagated receiver wavefield portion and the second back-propagated receiver wavefield portion into the receiver wavefield data. The method includes applying an imaging condition to the receiver wavefield data and the source wavefield data and generating, based on applying the imaging condition, visco-acoustic reverse time migration (VARTM) result data.

An apparatus obtains measurements from a seismic sensor, wherein the seismic measurements include a set of seismic waves having at least a subset of seismic multiples and a machine-readable medium having program code executable by a processor to cause the apparatus to determine seismic measurements of the seismic waves, fit reflectivity model based on a set of reflectivity models using a nonlinear scheme to the seismic measurements, and identify a subset of the seismic measurements corresponding to the subset of seismic multiples. The apparatus also includes program code to cause the apparatus to generate a set of reduced-noise seismic measurements based on attenuation of the subset of the seismic measurements.

A seismic sensor according to one or more embodiments may include: an acceleration measuring unit configured to repeatedly measure acceleration in three directions orthogonal to each other; and an index value calculator configured to operate in a measurement mode for calculating an index value of a magnitude of an earthquake based on a measurement result of acceleration in at least one direction by the acceleration measuring unit, and to operate in a standby mode with less power consumption than power consumption in the measurement mode. Then, the acceleration measuring unit monitors establishment of an activation condition that N times (M≥N≥2) measurement results in consecutive M times (M≥2) measurement results of acceleration in a predetermined direction exceed an acceleration threshold value. When the acceleration measuring unit detects establishment of the activation condition, the index value calculator transitions from the standby mode to the measurement mode.

An apparatus includes a seismic sensor to detect seismic waves having at least a subset of seismic multiples and a machine-readable medium having program code executable by a processor to cause the apparatus to determine seismic measurements of the seismic waves, generate a fitted reflectivity model based on a set of reflectivity models using a nonlinear scheme, and identify a subset of the seismic measurements corresponding to the subset of seismic multiples. The apparatus also includes program code to cause the apparatus to generate a set of reduced-noise seismic measurements based on the subset of the seismic measurements.

The present invention provides a method and device for determining an excitation point of a seismic source. The method includes: determining, according to a selected medium type, a distribution region corresponding to the selected medium type in a three-dimensional surface model corresponding to a preset surface range, where a preset position of the excitation point of the seismic source is located in the preset surface range, and a first mapping position corresponding to the preset position of the excitation point of the seismic source is located in the three-dimensional surface model; determining a second mapping position in the three-dimensional surface model according to the first mapping position and the determined distribution region; and determining, according to the second mapping position, a target position of the excitation point of the seismic source corresponding to the second mapping position in the preset surface range.

A system, a method and an autonomous network for vibration monitoring, the system comprising a master station preset for recording vibrations at a master trigger threshold; a secondary station, the secondary station and the master station being time synchronized, a server in communication with the master and secondary stations; wherein, the master station is configured to transmit a master trig time to the server and to start recording vibrations when the master trigger threshold is exceeded; the server is configured to store the master trig time; the secondary station is configured to detect the master trig time stored by the server, and upon detecting the master trig time, to record vibrations; and wherein the master and secondary stations are configured to transmit respective recorded vibrations to the server and the server is configured to classify the recorded vibrations in relation to a preset seismic threshold.