Abstract: A method for increasing similarity between a first seismic dataset and a second seismic dataset from at least one seismic survey of a subsurface. The first and second seismic datasets are migrated to a dip angle image domain. The migrated first and second seismic datasets are used in the dip angle image domain to calculate a set of decimating weights to be applied to the first seismic dataset and the second seismic dataset to maximize a similarity between the first seismic dataset and the second seismic dataset. The decimated weights are applied to the first and second seismic datasets, and an image of the subsurface is generated using the first seismic dataset and the second seismic dataset following application of the decimated weights.

Abstract: Systems and methods for deghosting seismic data using migration of sparse arrays are disclosed. The methods may include obtaining input seismic data, the input seismic data including a first set of seismic data recorded by a first set of seismic receivers located at a first depth, and a second set of seismic data recorded by a second set of seismic receivers located at a second depth. The method may further include migrating the first set of seismic data to an image grid, and migrating the second set of seismic data to the image grid. Additionally, the method may further include calculating a ghost wave based on the first and second sets of migrated seismic data, and deghosting the first set of migrated seismic data by removing the ghost wave.

Abstract: A system and method for discontinuous spectrum emission in seismic exploration is disclosed. The method may include determining a minimum frequency to be emitted by a seismic source in a frequency spectrum. The method may further include selecting a maximum frequency to be emitted by the seismic source in the frequency spectrum. The method may include identifying a portion of the spectrum between the minimum frequency and the maximum frequency where a reduced signal will be emitted by the seismic source. The method may finally include emitting, by the seismic source, a seismic signal according to the frequency spectrum and the identified portion of the frequency spectrum with the reduced signal.

Abstract: Systems and methods for improving or generating an image of a surveyed subsurface based on seismic interferometry. A method includes actuating interferometry-based sources over an area to be surveyed to generate seismic waves; recording seismic signals due to the interferometry-based sources, with seismic receivers; selecting traces corresponding to a pair of seismic receivers and an interferometry-based source such that ray paths between the interferometry-based source and the pair of seismic receivers contribute to a Green's function between the two receivers of the pair; cross-correlating the traces for calculating an earth's response associated with a ray propagating from a first seismic receiver of the pair to a second receiver of the pair; and generating an image based on the calculated earth's response.

Abstract: A system and method for reconstructing an incomplete data subset in seismic exploration is disclosed. The method includes receiving data based on a first emitted signal as a complete dataset. The first emitted signal is a range of frequencies between a starting frequency and a stopping frequency. The method further includes receiving data based on a second emitted signal as an incomplete data subset. The second emitted signal is a subset of the frequencies used by the first emitted signal between the starting frequency and the stopping frequency. The method further includes creating a reconstructed dataset by supplementing the incomplete data subset with the complete dataset and generating a seismic image based on the reconstructed dataset.

Abstract: A system and method are provided for filtering scatterer noise energy from land seismic waves using three dimensional (3D) iterative filtering in a cross-spread source-receiver pattern. The system and method isolate scatterer noise energy associated with a scatterer based on a filtering process performed using a scatterer referential time delay. Then, the isolated scatterer noise energy can be subtracted from the surface wave data. This process can be repeated for each scatterer in the covered area to remove each of their contributions, and can be performed, for example, after a preliminary filtering of the surface wave data using 3D fk filtering or the like.

Abstract: A system and method for discontinuous spectrum emission in seismic exploration is disclosed. The method may include determining a minimum frequency to be emitted by a seismic source in a frequency spectrum. The method may further include selecting a maximum frequency to be emitted by the seismic source in the frequency spectrum. The method may include identifying a portion of the spectrum between the minimum frequency and the maximum frequency where a reduced signal will be emitted by the seismic source. The method may finally include emitting, by the seismic source, a seismic signal according to the frequency spectrum and the identified portion of the frequency spectrum with the reduced signal.

Abstract: Methods and systems for optimizing the quantity and precision of processed seismic data based on reducing destructive interference of the seismic data. Sensitivity kernels are computed based on the medium of interest, e.g., source-receiver pairs, CDP collections and migrated collections, for a preselected wavefield parameter, e.g., travel-time, amplitude, slowness, etc., using a velocity model. Next, wavefield parameters are computed for a selected subset of the medium and are inverted or deconvolved with the sensitivity kernels to generate subsurface parameter variations.

Abstract: A method for increasing similarity between a first seismic dataset and a second seismic dataset from at least one seismic survey of a subsurface. The first and second seismic datasets are migrated to a dip angle image domain. The migrated first and second seismic datasets are used in the dip angle image domain to calculate a set of decimating weights to be applied to the first seismic dataset and the second seismic dataset to maximize a similarity between the first seismic dataset and the second seismic dataset. The decimated weights are applied to the first and second seismic datasets, and an image of the subsurface is generated using the first seismic dataset and the second seismic dataset following application of the decimated weights.

Abstract: Method, computer device and software for calculating a corrected temporal variation (dt1)depth or a corrected relative temporal variation (dt1/t1)depth of a first body wave based on a second body wave. The method includes receiving raw seismic data recorded with a receiver; calculating arrival-time variations for the first and second body waves; calculating first and second relative temporal variations for the first and second body waves; and correcting the first relative temporal variation based on the second relative temporal variation to obtain the corrected relative temporal variation or correcting the first temporal variation based on the second temporal variation to obtain the corrected temporal variation. The second wave is either a body wave or a surface wave.

Abstract: Method, computer device and software for calculating a corrected temporal variation (dt1)depth or a corrected relative temporal variation (dt1/t1)depth of a first body wave based on a second body wave. The method includes receiving raw seismic data recorded with a receiver; calculating arrival-time variations for the first and second body waves; calculating first and second relative temporal variations for the first and second body waves; and correcting the first relative temporal variation based on the second relative temporal variation to obtain the corrected relative temporal variation or correcting the first temporal variation based on the second temporal variation to obtain the corrected temporal variation. A body wave is a wave that experiences at least one reflection before being recorded by the receiver.

Abstract: A system and method are provided for filtering scatterer noise energy from land seismic waves using three dimensional (3D) iterative filtering in a cross-spread source-receiver pattern. The system and method isolate scatterer noise energy associated with a scatterer based on a filtering process performed using a scatterer referential time delay. Then, the isolated scatterer noise energy can be subtracted from the surface wave data. This process can be repeated for each scatterer in the covered area to remove each of their contributions, and can be performed, for example, after a preliminary filtering of the surface wave data using 3D fk filtering or the like.

Abstract: Method, computer device and software for calculating a corrected temporal variation (dt1)depth or a corrected relative temporal variation (dt1/t1)depth of a first body wave based on a second body wave. The method includes receiving raw seismic data recorded with a receiver; calculating arrival-time variations for the first and second body waves; calculating first and second relative temporal variations for the first and second body waves; and correcting the first relative temporal variation based on the second relative temporal variation to obtain the corrected relative temporal variation or correcting the first temporal variation based on the second temporal variation to obtain the corrected temporal variation. A body wave is a wave that experiences at least one reflection before being recorded by the receiver.

Abstract: Method, computer device and software for calculating a corrected temporal variation (dt1)depth or a corrected relative temporal variation (dt1/t1)depth of a first body wave based on a second body wave. The method includes receiving raw seismic data recorded with a receiver; calculating arrival-time variations for the first and second body waves; calculating first and second relative temporal variations for the first and second body waves; and correcting the first relative temporal variation based on the second relative temporal variation to obtain the corrected relative temporal variation or correcting the first temporal variation based on the second temporal variation to obtain the corrected temporal variation. The second wave is either a body wave or a surface wave.

Abstract: Computing device, software and method for identifying a source mechanism associated with a microseismic event taking place in a subsurface of the earth. The method includes receiving traces associated with a plurality of receivers located in a grid above the subsurface; dividing the grid in a set of sub-blocks, determining, for each sub-block, a corresponding summation element based on traces associated with the corresponding sub-block; identifying a predetermined number of patterns that are associated with plural source mechanisms; multiplying each summation element by a polarization coefficient according to a corresponding pattern; calculating for each pattern, a semblance function based on summation elements of the sub-blocks; and identifying the source mechanism of the microseismic event based on the semblance function.

Abstract: The invention relates to a method for synchronizing a radio terminal in a radio-communication network with a received signal flow comprising a predefined synchronization sequence repeated at predefined time intervals. According to the invention, the method consists in generating correlation profiles at the radio terminal by correlating a part of said signal flow with the synchronization sequence to reveal correlation peaks and accumulating as many correlation profiles as necessary, until a threshold level is reached by at least the largest correlation peak. The threshold level is updated, during the accumulation, depending on a background noise level estimated in the signal flow to dynamically determine if the synchronization sequence has been detected at the radio terminal.

Abstract: Path selection method in a CDMA receiver for the selection of the true path of a transmission channel, comprising the step of comparing the profile energy with a threshold, characterized in that the threshold is dynamically determined as a function of the mean of noise and interference paths derived from the transmission channel profile estimation.

Abstract: The invention relates to a method for synchronizing a radio terminal in a radio-communication network with a received signal flow comprising a predefined synchronization sequence repeated at predefined time intervals. According to the invention, the method consists in generating correlation profiles at the radio terminal by correlating a part of said signal flow with the synchronization sequence to reveal correlation peaks and accumulating as many correlation profiles as necessary, until a threshold level is reached by at least the largest correlation peak. The threshold level is updated, during the accumulation, depending on a background noise level estimated in the signal flow to dynamically determine if the synchronization sequence has been detected at the radio terminal.