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.

Techniques are disclosed relating to deblending of sources in multi-source geophysical survey data, including marine or land-based data. Recorded data may be aligned to a primary source. A deblending procedure may be iteratively applied to produce a residual term and deblended estimates for the primary source and one or more secondary sources. Following an iteration of the deblending procedure, the resultant data may be sorted according to a domain that renders the one or more secondary sources incoherent with respect to the primary source. The domain used for sorting may be different from a domain used to sort during an immediately prior iteration. In embodiments, the deblending procedure may use coherency filtering, and the coherency filtering may be weighted according to a signal-to-noise metric generated from the data being deblended.

Systems and methods include a method for deblending signal and noise data. A shot domain for actual sources, a receiver domain for virtual sources, and a receiver domain for actual sources are generated from blended shot data. A dictionary of signal atoms is generated. Each signal atom includes a small patch of seismic signal data gathered during a small time window using multiple neighboring traces. A dictionary of noise atoms is generated. Each noise atom includes a small patch of seismic noise data gathered during a small time window using multiple neighboring traces. A combined signal-and-noise dictionary is generated that contains the signal atoms and the noise atoms. A sparse reconstruction of receiver domain data is created from the combined signal-and-noise dictionary. The sparse reconstruction is split into deblended data and blending noise data based on atom usage to create deblended shot domain gathers for actual sources.

A method and system for locating a reflector in a formation. The method may comprise broadcasting a sonic waveform as a shear formation body wave or a compressional formation body wave into the formation, recording a reflected wave from a reflector with the one or more receivers as dipole data by the dipole receiver and quadrupole data by the quadrupole receiver, and processing the dipole data and the quadrupole data with an information handling system to determine a location of the reflector from the borehole sonic logging tool. The system may comprise a borehole sonic logging tool and an information handling system. The borehole sonic logging tool may comprise one or more transmitters configured to transmit a sonic waveform into a formation and one or more receivers configured to record a reflected wave as a dipole receiver for dipole data and a quadrupole receiver for quadrupole data.

A distributed acoustic sensor is positioned within a wellbore of a geologic formation. Seismic waves are detected using the distributed acoustic sensor. A raw seismic profile is generated based on the detected seismic waves. Resonant noise is identified and reduced in seismic data associated with the raw seismic profile.

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.

Techniques are disclosed relating to deblending of sources in multi-source geophysical survey data, including marine or land-based data. Multiple sets of deblended receiver traces are generated by iteratively applying a coherency filter to estimated sets of deblended receiver traces and updating a residual until a termination condition is reached. In some embodiments, applying the coherency filter during a current iteration may include determining coefficients of the coherency filter based on estimated sets of deblended receiver traces from an immediately prior iteration. In further embodiments, applying the coherency filter may include applying a 3D projection filter, such as an fxy projection filter.

A method includes receiving modelled seismic data that is to be recognized by the at least one classification and/or segmentation processor. The modelled seismic data can be represented within a transform domain. The method includes generating an output via the at least one processor based on the received modelled seismic data. The method also includes comparing the output of the at least one processor with a desired output. The method also includes modifying the at least one processor so that the output of the processor corresponds to the desired output.

Deblending and deghosting seismic data may include processing blended seismic data acquired after actuation of a first seismic source located at a first depth and a second seismic source located at a second depth. The processing may comprise deblending and deghosting the blended seismic data based on a difference in ghost responses of the first seismic source and the second seismic source.

An example method includes at least partially positioning within a wellbore an optical fiber of a distributed acoustic sensing (DAS) data collection system. Seismic data from the DAS data collection system may be received. The seismic data may include seismic traces associated with a plurality of depths in the wellbore. A quality factor may be determined for each seismic trace. One or more seismic traces may be removed from the seismic data based, at least in part, on the determined quality factors.