Abstract: A method for determining a shape of a streamer to be towed under water for collecting seismic data. The method includes receiving a velocity model for the subsurface; selecting a first profile for a streamer to be used to survey the subsurface; calculating ghosts and/or residual ghosts and/or residual ghost spectra for a plurality of reflectors of the subsurface; and determining that the first profile is appropriate for surveying the subsurface when at least one criterion, related to the ghosts, residual ghosts and/or residual ghost spectra is met.

Abstract: Apparatus, computer instructions and method for combining first and second records to form a substantially deghosted seismic record.

Abstract: Computing device, computer instructions and method for up-down separation of seismic data. The method includes receiving the seismic data, which includes hydrophone data and particle motion data; performing a first up-down separation, which is independent of a ghost model, using as input the hydrophone data and the particle motion data, to obtain first up-down separated data; performing a second up-down separation by using as input a combination of (i) the hydrophone data and/or the particle motion data and (ii) the first up-down separated data, wherein an output of the second up-down separation is second up-down separated data; and generating an image of the subsurface based on the second up-down separated data.

Abstract: A composite electromagnetic (EM) system and method for measuring naturally occurring magnetic fields and controlled magnetic fields. The composite EM system includes a housing, an audio-magnetotelluric (AMT) system attached to the housing and measuring natural magnetic fields generated by earth, a frequency-domain EM (FDEM) system attached to the housing and measuring controlled magnetic fields generated by a controlled source, and a position and orientation (POS) system attached to the housing and configured to calculate an orientation and a position of the AMT system and housing relative to the earth. The housing is configured to be attached to an aircraft for being airborne while measuring the natural magnetic fields and the controlled magnetic fields.

Abstract: Fracture orientation ambiguity in the results of amplitude variation with offset and azimuth inversion is overcome by using additional geological information. Methods, apparatus and executable codes stored on non-transitory media cause, for each interface encountered by traces in a CMP gather, calculating angle-dependent azimuthal Fourier coefficients, performing a nonlinear inversion of amplitude versus offset and azimuth, AVOAz, equations built using the angle-dependent azimuthal Fourier coefficients to determine possible fracture orientations, and selecting one of the possible fracture orientations using constraints based on the additional geological information.

Abstract: A device, medium and method for deblending seismic data associated with a subsurface of the earth. The method includes a step of receiving seismic data S recorded with one or more seismic receivers, wherein the seismic data S includes shot recordings generated by first and second source arrays that are simultaneously actuated; a step of detecting incoherent energy of the seismic data S using a median filter; a step of replacing incoherent parts of the seismic data with a projection filter to obtain deblended data for one of the two or more source arrays; and a step of generating in a computing device an image of the subsurface based on the deblended data.

Abstract: A method for evaluating anisotropy parameters using statistical moments calculates second and third central moments using reflectivity values associated with pairs of incidence and azimuth angles. The method further determines tangential and normal weaknesses for the location using the calculated second and third central moments for different incident angles. Linear and non-linear inversions of statistical moments are used to estimate the fracture weaknesses, anisotropic gradient (biased and unbiased), anellipticity variation and unambiguous orientation.

Abstract: A computing device, computing medium and method for generating an image of a tilted orthorhombic medium. The method includes receiving seismic data related to the tilted orthorhombic medium; calculating a wave propagation with a processing device by applying a second-order equation for reverse time migration to the seismic data to generate a tilted orthorhombic wave propagation; and generating the image of the tilted orthorhombic medium based on the tilted orthorhombic wave propagation.

Abstract: Methods for processing seismic data acquired with non-impulsive moving sources are provided. Some methods remove cross-talk noise from the seismic data using emitted signal data and an underground formation's response estimate, which may be iteratively enhanced. Some methods perform resampling before a spatial or a spatio-temporal inversion. Some methods compensate for source's motion during the inversion, and/or are usable for multiple independently moving sources.

Abstract: One or more portions of a streamer or other equipment of a seismic survey system (e.g., birds, buoys, deflectors, etc.) are covered with protective removable skin sections. A protective removable skin section includes a flexible sheet and a reversible closure system configured to join edges of the flexible sheet. The protective removable skin section may be mounted onboard of a vessel, when the equipment is deployed.

Abstract: Global inversion of multi-vintage seismic data uses simulated annealing to minimize a cost function simultaneously for all vintages and all angle stacks to yield values of geophysical properties. Each vintage is generated from an independent seismic survey of a subsurface structure conducted over a distinct period of time and includes seismic traces and angle stacks. An initial model of the subsurface structure is used and includes values for geophysical properties and time shift maps between vintages. The time shift map contains shifts in the seismic trace between vintages. The cost function includes a time shift map term for the difference between the time shift map and a calculated time shift of the seismic trace between vintages and is based on a proposed perturbation to at least one of the geophysical properties. The time shift map is also used as a global constraint on proposed perturbations of subsurface properties.

Abstract: Computing device, computer instructions and method for correcting an image, of a surveyed surface, due to a free-surface reflection. The method includes calculating a free surface reflection operator for a seismic source displaced in water based on a position of the source, and an air-water interface datum; receiving recorded seismic data d recorded with seismic sensors (r), wherein the recorded seismic data is associated with a pressure and/or a particle motion produced by a seismic wave in earth; correcting the recorded seismic data d based on the free surface reflection operator to obtain transformed seismic data; and generating an image of the surveyed subsurface, based on the transformed seismic data, wherein the image is indicative of various layers of the earth. The free surface reflection operator varies while a source signal is being emitted by the source.

Abstract: Methods and systems for processing seismic data for improving an image of a surveyed subsurface. The method includes receiving seismic data associated with the surveyed subsurface; applying a multi-layer non-linear slope tomography algorithm to iteratively calculate a new boundary of a first layer of the surveyed subsurface and to calculate a velocity attribute of a second layer of the surveyed subsurface; and generating an improved image of the surveyed subsurface based on the new boundary of the first layer and the velocity attribute of the second layer.

Abstract: Computing device, computer instructions and method for improving accuracy of an image of a surveyed subsurface. The method includes a step of receiving seismic data (D) recorded with seismic sensors; a step of deghosting the seismic data (D) using a sparseT-Pinversion algorithm together with a low-rank optimization scheme and a high-cut filter to calculate ghost-free wave-fields (U0(t,x,y)) in the time-space domain; and a step of processing the ghost-free wave-fields (U0(t,x,y)) to generate the image of the surveyed subsurface.

Abstract: A system for immersion cooling computing system equipment includes a container, a volume of cooling liquid disposed in the container, a computing system equipment holder disposed in the volume of cooling liquid and a liquid-liquid heat exchanger attached to and supported by the computing system equipment holder. The liquid-liquid heat exchanger is disposed in the volume of cooling liquid.

Abstract: A method for estimating a time variant signal representing a seismic source obtains seismic data recorded by at least one receiver and generated by the seismic source, the recorded seismic data comprising direct arrivals and derives the time variant signal using an operator that relates the time variant signal to the acquired seismic data, the operator constrained such that the time variant signal is sparse in time.

Abstract: Methods and apparatuses compute and apply surface-consistent frequency-dependent phase corrections, to traces extracted from seismic survey data, using a multi-scale iterative approach.

Abstract: Computing device and methods process seismic data sets associated with the same surveyed subsurface but recorded with different spatial sampling and temporal bandwidths. The first seismic data is used to guide processing of the second seismic data. An image of the subsurface is generated based on processed second seismic data.

Abstract: The present disclosure includes a method including determining a spatial region for analysis and selecting a segment of time for analysis, analyzing and correcting a plurality of traces from a plurality of receivers using an iterative non-linear inversion algorithm, wherein each iteration of the non-linear algorithm corrects the plurality of traces using at least one set of parameters defining a microseismic event, determining whether a final stack value of the plurality of traces corrected based on the at least one set of parameters of a final iteration of the iterative non-linear inversion algorithm exceeds a predetermined threshold and upon a determination that the final stack value exceeds the predetermined threshold, detecting a microseismic event defined by the at least one set of parameters of final iteration. The present disclosure also includes associated systems and computer-readable media.

Abstract: Systems and methods for reducing survey time while enhancing acquired seismic data quality are provided. Data corresponding to plural source lines are acquired simultaneously, using sources at cross-line distance at least equal to their illumination width, with at least one source being towed above a streamer spread.