Methods include receiving a set of seismic data including a seismic signal generated over the course of a set period of time as a time scale, partitioning the seismic signal into a predetermined integer number greater than one of partitioned seismic signals each associated with a respective fixed position associated with a respective time interval as a portion of the time scale, applying a pulse compression technique to each partitioned seismic signal of the predetermined number of partitioned seismic signals to generate a compressed partitioned seismic signal corresponding to each partitioned seismic signal of the predetermined number of partitioned seismic signals, and inserting the compressed partitioned seismic signal corresponding to each partitioned seismic signal of the predetermined number of partitioned seismic signals in parallel into a velocity model builder. In addition, the methods include summing generated results therefrom to model the seismic signal for the time scale.

Noise can be attenuated in marine seismic data from a marine seismic survey. A first near-continuous measurement of a wavefield and a second near-continuous measurement of the wavefield recorded from a marine seismic survey can be equalized, a coherent portion of the equalized second near-continuous measurement can be collapsed, and a noise model can be derived. The noise model can be subtracted from the second near-continuous measurement.

Noise can be attenuated in marine seismic data from a marine seismic survey. A first near-continuous measurement of a wavefield and a second near-continuous measurement of the wavefield recorded from a marine seismic survey can be equalized, a coherent portion of the equalized second near-continuous measurement can be collapsed, and a noise model can be derived. The noise model can be subtracted from the second near-continuous measurement.

A method of underwater tsunami detection includes detecting a trigger event using disruption of at least one of a plurality of hard disk drives (HDDs), each different one of the plurality of HDDs in a different one of a plurality of autonomous underwater vehicles (AUVs). A time and location of each of the at least one HDD for the trigger event is logged. Based on at least one of the HDD disruptions, times, and locations of the at least one HDD of the plurality of HDDs, a size, strength, and direction of a tsunami caused by the trigger event is determined. Information regarding the tsunami is transmitted to a monitoring station.

A dip angle-steering median filtering method based on a niche differential evolution algorithm, comprising the following steps: dividing a data to be processed into a series of overlapping time-space windows; obtaining an event energy curve in a time-space window and obtaining an event position according to a local maximum value of the event energy curve; obtaining event dip angles and coherence values of the event dip angles through the niche differential evolution algorithm at the event position; filtering the event dip angles according to the event dip angles and the coherence values of the event dip angles; and performing a median filtering sequentially along a filtering dip angle. The disclosure can simultaneously obtain all dip angles of intersecting events and a true three-dimensional feature enable the present disclosure to obtain a better filtering effect.

Systems, methods, and computer-readable media for using full waveform inversion for imaging surveyed mediums are provided. The full waveform inversion uses a Sifrian functional to fully leverage Hessian information and update a model by augmenting and assembling data derived from the Sifrian functional when equilibrated. The Sifrian inversion produces high resolution images of the surveyed medium typically only seen with full Hessian inversions and can produce such images without requiring supercomputer computation power or extremely long computation time.

A measurement device intended to be immersed in water, includes a set of arms and a reference axis, the measurement device being able to be in a deployed configuration, the measurement device comprising a set of measurement units borne by arms of the set of arms and each comprising an acoustic-waves sensor, the set of measurement units being configured and arranged in such a way as to generate a torque on the measurement device about the reference axis upon a vertical translational movement of the measurement device in the deployed configuration, the measurement device comprising compensation means configured and arranged in such a way as to generate another torque on the measurement device about the reference axis during the vertical translational movement, the other torque being directed in the opposite direction to the torque and having an intensity less than twice that of the torque.

A measurement device intended to be immersed in water, includes a set of arms and a reference axis, the measurement device being able to be in a deployed configuration, the measurement device comprising a set of measurement units borne by arms of the set of arms and each comprising an acoustic-waves sensor, the set of measurement units being configured and arranged in such a way as to generate a torque on the measurement device about the reference axis upon a vertical translational movement of the measurement device in the deployed configuration, the measurement device comprising compensation means configured and arranged in such a way as to generate another torque on the measurement device about the reference axis during the vertical translational movement, the other torque being directed in the opposite direction to the torque and having an intensity less than twice that of the torque.

Some embodiments are directed to a multiplexed fiber sensor for a fiber optic hydrophone array, including a signal receiver configured to receive a signal from the fiber optic hydrophone sensor array and an interferometer. The interferometer is configured to produce a first signal component and a second signal component from the signal received from the hydrophone array, and also provided with a first polarisation controller configured to control the polarisation of the first signal component and a second polarisation controller configured to control the polarisation of the second signal component. A modulated carrier signal generator configured to generate a modulated carrier signal component based on the first signal component is also provided. A detector configured to output a demodulated output signal from the modulated signal component and the second signal component is included, wherein the modulated signal component and the second signal component output separately from the interferometer.

A harness plug and methods of use. Example devices include an arcuate portion and a lateral portion disposed at an outer periphery of the arcuate portion. The arcuate portion is configured to engage with arcuate portion of a hole within a spacer. A method of using the harness plug includes molding a harness plug about a portion of a cable bundle and inserting the cable bundle into an arcuate portion of a hole in the spacer through a lateral portion of the first hole. The harness plug is pressed into the arcuate portion of a hole in the spacer. A streamer spacer for use with the harness plug includes a hole having a portion having an arcuate shape and a second portion lateral to and abutting the arcuate portion and extending to a periphery of an elongate body of the streamer spacer.