Abstract: A shot interval between activations of at least one frequency-controllable survey source is determined, where the shot interval is determined based on an expected frequency of an output of the at least one frequency-controllable survey source. The at least one frequency-controllable survey source is activated using the determined first shot interval.

Abstract: A method for analyzing seismic data by generating a post-migration common image gather in a dip angle domain from measured seismic data; detecting concave features related to reflection events in the common image gather and apexes; filtering out part of the concave features in the common image gather in a vicinity of the detected apexes; applying a hybrid Radon transform to the filtered common image gather to separate residues of the concave features from other image features related to diffraction events; and applying an inverse hybrid Radon transform to an image containing the separated features related to diffraction events to obtain a transformed common image gather in the dip angle domain.

Abstract: A method can include receiving an inside stack and an outside stack; generating a multiple reflections model based at least in part on the inside stack and the outside stack; receiving multidimensional seismic data that includes representations of primary reflections and multiple reflections; and generating processed multidimensional seismic data by applying the multiple reflections model to the multidimensional seismic data. Various other apparatuses, systems, methods, etc., are also disclosed.

Abstract: A method of attenuating interbed multiples in multiply-reflected seismic waves is performed at a computer system, the method comprising: providing multiple beams of seismic data and an earth model related to a geological volume; selecting one of the beams as an input beam associated with a pair of source and detector located near a top surface of the geological volume; determining at least one of (i) a source-side stationary pegleg arrival and a corresponding detector-side primary beam and (ii) a detector-side stationary pegleg arrival and a corresponding source-side primary beam; predicting an interbed multiples beam using at least one of (i) the detector-side primary beam delayed by the source-side stationary pegleg arrival and (ii) the source-side primary beam delayed by the detector-side stationary pegleg arrival; and deconvolving the predicted interbed multiples beam with the input beam to remove at least a portion of interbed multiples present in the input beam.

Abstract: Data representing a first multiple is predicted, based on first survey data for a target structure, using a multidimensional model of a layer in which the first multiple occurs. Modified survey data is produced by performing a subtraction of the predicted data representing the first multiple from the first survey data. Based on the modified survey data, data representing a second multiple is predicted using the multidimensional model.

Abstract: The invention pertains generally to the field of seismicity. The method of the invention provides an objective criteria for decision when determining whether or not the seismic activity (seismicity) occurring within a certain area is induced by human activity, specifically geophysical activity, particularly associated with the mining/extracting industry, or whether the seismicity is naturally occurring. The method can be useful for production companies, regulatory authorities, or insurance companies.

Abstract: Method for decomposing a complexly shaped object in a data set, such as a geobody (31) in a seismic data volume, into component objects more representative of the true connectivity state of the system represented by the data set. The geobody is decomposed using a basis set of eigenvectors (33) of a connectivity matrix (32) describing the state of connectivity between voxels in the geobody. Lineal subspaces of the geobody in eigenvector space are associated with likely component objects (34), either by a human interpreter (342) cross plotting (341) two or more eigenvectors, or in an automated manner in which a computer algorithm (344) detects the lineal sub-spaces and the clusters within them.

Abstract: Disclosed herein is method of computing formation attributes from acoustic measurements in a borehole. The acoustic measurements can be made by operating an acoustic source at multiple frequencies to excite the formation and operating receivers at multiple, longitudinally spaced receiver stations to receive acoustic energy from the formation. The method can include: deriving phase data from the spectrum of received acoustic signals; unwrapping phase information of the phase spectrum data; determining two or more values of difference of phase between acoustic signals at each of a range of frequencies each based on a single generated signal received at two or more pairs of adjacent said receiver stations; generating a value of slope of phase difference values; and in any case of slope ambiguity, unwrapping phase difference information and deriving a dominant slope, at each frequency, from which slowness of the acoustic signal in the formation can be derived.

Abstract: Presented are methods and systems for regularizing content of multi-component seismic data. The method includes a step of receiving the seismic data, wherein the seismic data includes pressure and particle motion measurements and a step of regularizing and frequency optimizing the seismic data to desired positions based on Fresnel zones selected at various depths in a subsurface to obtain a regularized seismic dataset.

Abstract: A vibrator-coupled ground filter improves seismic data recorded during a seismic operation. This filter is based on a ground model that takes into consideration the vibrator system, the coupling system between the baseplate and captured ground, and the coupled ground system. Using acceleration data from the baseplate and the reaction mass, the ground model can be used to derive particular variables for the ground model to help characterize the system. Using the derived variables in a ground filter, the recorded seismic data can be corrected to remove errors in the trace data produced by typical assumptions.

Abstract: A fully automated method for correcting errors in one interpretation (13) of seismic data based on comparison to at least one other interpretation (14) of the same subsurface region. The errors may occur in any feature of the seismic data volume, for example a horizon, surface, fault, polyline, fault stick, or geo-body. In some embodiments of the invention, an error may be a hole in a horizon (53), and the whole is patched by a piece of a horizon in another interpretation (55). In an alternative embodiment of the invention, a single interpretation may be used to repair itself, for example by identifying similarly shaped, adjacent horizons (67), and merging them (68).

Abstract: A technique includes receiving seismic data acquired in a seismic survey. The technique includes determining a geophysical trend of trace amplitudes indicated by the seismic data based on non-linear regression and performing quality control analysis on the seismic data based on the determined trend.

Abstract: Prospect assessment and play chance mapping tools are provided. For assessing potential resources, example systems provide dynamically linked chance maps, transformed in real time from geological properties. Input geological maps or other data are dynamically linked to resulting chance maps, so that changes in the input maps automatically update the chance map in real time. Users can generate a custom risk matrix dynamically linking geological maps with chance maps via interface tools, dropping maps directly into the matrix. A transform may programmatically convert the geologic domain to the chance domain. The user can navigate input maps, select areas of interest, and drag-and-drop geologic properties into an uncertainty engine and distribution builder for uncertainty assessment based on geologic reality. A merge tool can programmatically unify multiple geological interpretations of a prospect. The merge tool outputs a single chance of success value for multiple geologic property values at each grid node.

Abstract: Method for multi-parameter inversion using elastic inversion. This method decomposes data into offset/angle groups and performs inversion on them in sequential order. This method can significantly speed up convergence of the iterative inversion process, and is therefore most advantageous when used for full waveform inversion (FWI). The present inventive approach draws upon relationships between reflection energy and reflection angle, or equivalently, offset dependence in elastic FWI. The invention uses recognition that the amplitudes of small angle (near offset) reflections are largely determined by acoustic impedance alone (1), independent for the most part of Vp/Vs. Large angle (middle and far offset) reflections are affected by Ip, Vp/Vs (2) and other earth parameters such as density (3) and anisotropy.

Abstract: The present disclosure provides a system and method for automatically identifying and classifying seismic terminations within a seismic data volume. A set of surfaces is obtained (step 303) describing the seismic data volume. A plurality of seismic terminations is identified within the set of surfaces (step 307). Based upon seismic attributes or geometric criterion, a termination direction can be determined (step 309) for at least one termination.

Abstract: A recording system and method for conducting seismic surveys including cordless battery-operated digital recorders, each employing an integral global positioning system receiver that is only periodically enabled for the purpose of establishing synchronized acquisition clock signals among all the recorders. The satellite receiver adjustment cycle is varied depending on past acquisition clock accuracy and temperature changes. A time stamp is recorded with the digitized seismic data in non-volatile memory. The memory is sized to allow extended periods of operation. Each recorder preferably includes a low-power system timer that may be used as a timer to remotely turn on and off the recorders according to a pre-programmed schedule to conserve power when the system is not in use. Electronic components are idled or de-energized when not needed.

Abstract: A method, having application to petroleum exploration or production, for picking the arrival time of seismic waves and use thereof for orienting the components of a multi-component sensor. After acquisition of seismic data using a VSP type method, with a multi-component sensor, a module signal is constructed by calculating the square root of the sum of the squares of at least two orthogonal seismic components. Arrival times of a direct seismic wave are then picked on an amplitude extremum of this module signal. Based on this picking, the seismic components can then be oriented in a unique reference frame whatever the depth of the sensor. A time window is defined on either side of the picked arrival times and the azimuthal direction is determined by maximizing the energy of the horizontal components within this time window. Finally, the three components are oriented in a reference frame defined with respect to the azimuthal direction, which is identical for each depth.

Abstract: Tools and methods for monitoring a subterranean formation is provided. Methods for monitoring include: creating a time-lapse azimuth stack between an azimuth stack on a first seismic survey and an azimuth stack on a second seismic survey; identifying a lowest root mean square energy and a highest root mean square energy for each time-lapse azimuth stack; and recording an azimuth with largest overall root mean square energy.

Abstract: Disclosed herein are various embodiments of a method and apparatus to enhance spatial sampling in all nominally horizontal directions for Dual-Sensor seismic data at the bottom of a body of water such as the ocean. The sensor apparatus on the water bottom is comprised of sensing elements for linear particle motion, for rotational motion, for pressure measurement, for pressure gradients, and for static orientation. Stress and wavefield conditions known at the water bottom allow numerical calculations that yield enhanced spatial sampling of pressure and nominally vertical linear particle motion, up to double the conventional (based on physical sensor locations) Nyquist spatial frequency in two nominally horizontal independent directions. The method and apparatus have a wide range of application in Ocean Bottom Seismic 3D, 4D, and Permanent Reservoir Monitoring surveys, and other marine seismic surveys, in oil and gas exploration and production.

Abstract: A method can include receiving seismic traces associated with a geologic environment; determining time domain stretch values for individual wavelets in at least a portion of the seismic traces with respect to a spatial dimension of the geologic environment; and estimating at least one Q-factor value for at least a portion of the geologic environment via a comparison of the time domain stretch values to a Q-factor model.

Abstract: A system and method for processing seismic data on one or more co-processor devices that are operatively coupled to a host computing system via a communications channel. The compression of input data transmitted to the co-processor device and/or the size of the storage provided on the co-processor device may enhance the efficiency of the processing of the data on the peripheral device by obviating a bottleneck caused by the relatively slow transfer of data between the host computing system and the co-processor device or by the relatively slow transfer of data within the co-processor device between the co-processor information storage and the co-processor.

Abstract: The transmission coefficient method for AVO (amplitude variation with offset) seismic analysis computes incident-to-transmitted pressure wave and incident-to-transmitted shear wave data in a manner that is compatible with existing AVO applications for analysis on the transmission coefficients of VSP data. Amplitude variation with offset (AVO) computation techniques known in the art provide estimates of pressure wave, shear wave and pseudo-Poisson's reflectivity. Such estimates are based on the Aki-Richards approximation of Zoeppritz's formulation of reflection amplitude and polarity variation with respect to incidence angle. The Zoeppritz equations describe the amplitudes of body waves when incident on an interface, resulting in a scattering matrix in which all possible incident and generated modes are addressed. The present method further simplifies the Aki and Richards computations to facilitate further AVO analysis.

Abstract: The present disclosure relates generally to well logging and measurement in subterranean formations and more particularly, the present disclosure relates to a system and method for identifying anisotropic formations, such as fractures and fracture patterns, in subterranean formations. The method uses waveforms transmitted from a monopole source. After finding the Root Mean Square energy from at least four quadrants, the energy data is normalized. At least one minimum RMS energy point is identified and the azimuth of that minimum is also identified. The azimuth and the minimum are instructive in defining fracture patterns and characteristics.

Abstract: Methods and computing systems for processing collected data are disclosed. In one embodiment, a method is provided for predicting a plurality of surface multiples for a plurality of target traces in a record of multi-component seismic data acquired in a survey area. The method may select a target trace. The method may select an aperture of potential downward reflection points for the target trace. The method may calculate dip propagation attributes from the multi-component seismic data. The method may map the dip propagation attributes into a multiple contribution attribute gather based on the aperture. The method may modify the aperture based on the multiple contribution attribute gather. The method may then predict multiples for the selected target trace using the modified aperture.

Abstract: A method of processing geophysical signals obtained by—monitoring the response of the earth to an source using a plurality of receivers is described including the evaluation of sums or integrals of functions of weighted signal values over a one or multidimensional domain such that the domain is split into a plurality of simplices and the signal values are interpolated across the simplices using a non-linear approximation of the function, the approximation including signals and gradients of the signals, and the evaluated sums or integrals are used to obtain a representation of characteristics of the earth.

Abstract: Methods and systems for designing or configuring a microseismic monitoring network are described. The design is based on a regular and homogeneous repartitioning of seismic sensor locations associated with a focal sphere. The methods and systems determine an optimal sampling of the focal sphere of microseismic events and a takeoff angle associated with each of the optimal sampling points. The sampling points are propagated to the surface based on the associated rays and any of a plurality of ray tracing techniques.

Abstract: In response to at least one input criterion, one or more target positions in an acquisition domain are determined for processing of survey data, where the survey data is acquired by survey equipment in the acquisition domain having a first set of dimensions, and where the processing of the survey data is to be performed in a processing domain having a second set of dimensions different from the first set of dimensions.

Abstract: A technique includes a method and apparatus for simultaneous joint inversion of surface wave and refraction data to identify near surface geophysical and geological properties.

Abstract: A technique includes modeling interpolated seismic measurements as a random process characterized by seismic measurements acquired at a set of sensor locations and an interpolation error. The technique includes determining the interpolated seismic measurements based at least in part on a minimization of the interpolation error.

Abstract: Method for automated and quantitative assessment of multiple direct hydrocarbon indicators (“DHI's”) extracted from seismic data. DHI's are defined in a quantitative way (33), making possible a method of geophysical prospecting based on quantification of DHI anomalies. Instead of working in a particular spatial region of seismic data pre-defined as a hydrocarbon opportunity, the present invention works on entire data volumes derived from the measured seismic data (31), and identifies opportunities based on quantified DHI responses. In some embodiments, a series of algorithms utilizes the geophysical responses that cause DHI's to arise in seismic data to search entire data sets and identify hydrocarbon leads based on the presence of individual and/or combinations of DHI's (34).

Abstract: A system and method may, based on a 3D seismic data set seed point, execute a seed picking algorithm, using the first point for picking a set of second points from the data set, setting each of the points in the set of second points as the first point and repeating the algorithm. An iteration number or other attribute may be assigned to the points, the iteration number corresponding to the number of times the algorithm repeated to process the point. The attribute or a number of attributes may be displayed as a visual characteristic for each point. An iterative process may be applied to a set of seismic data points, starting at a seed data point and finding a set of next iteration seed points from among the set of points neighboring the seed point, continuing only with next iteration seed points, and recording for each of a set of data points the number of points that are found by the process when the point is used as a seed data point.

Abstract: A geophysical target-oriented approach is proposed to derive seismic sensitivity to 4D positioning mismatches, which focuses on the impact on the reflective response from the reservoir. The sensitivity indicators provide information about the seismic impact, in terms of reservoir imaging, of a surface positioning mismatch. Some embodiments capitalize on the use of legacy data, enabling a fast-track analysis to be carried out on the velocity model to extract trends and mapping of lateral geological variability.

Abstract: Methods and systems for interpolating seismic data estimate a first frequency spectrum associated with the seismic data using a matching point (MP) algorithm having a pre-computed term. A second frequency spectrum is also estimate for the seismic data, using the MP algorithm, an anti-aliasing mask and the estimated first regular frequency spectrum. From the second frequency spectrum, the interpolated seismic data can be determined by performing an inverse fast Fourier Transform thereon.

Abstract: Presented are methods and systems for reducing or eliminating spurious error or cross-terms when using bilinear functions in a time-frequency analysis. A maximum entropy method is applied to a Wigner-Ville distribution of seismic traces to provide a robust and high resolution time-frequency representation of the seismic traces.

Abstract: A system and method of interpolating seismic data is provided. The system and method form a plurality of pairwise Hankel tensors from acquired seismic data, and a respective pairwise Hankel tensor for each of a plurality of originally collected frequency slices, perform tensor completion on each of said pairwise Hankel tensors to recover a plurality of interpolated frequency slices, and combine said plurality of interpolated frequency slices with said originally collected frequency slices to form a set of trace data of a geographical area of interest.

Abstract: A method for estimating uncertainties in determining hypocenters of seismic events occurring in subsurface formations according to one aspect includes determining estimates of event locations by choosing local peaks in summed amplitude of seismic energy detected by an array of sensors disposed above an area of the subsurface to be evaluated. For each peak, the following is performed: recomputing the summed amplitude response for a selected set of points of comprising small perturbations in time and space from the estimated event locations; computing second derivatives of log likelihood function from the stacked responses at the estimated location and the perturbed locations; assembling the second derivatives into a Fisher information matrix; computing an inverse of the Fisher information matrix; determining variances of estimated parameters from the elements from the diagonal of the inverted matrix; and computing standard deviations of the estimated parameters by calculating a square root of the variances.

Abstract: Translational data acquired by at least one seismic sensor is received. Gradient sensor data acquired by at least one gradient sensor is received. Estimated translational data at a position away from at least one position of the at least one seismic sensor is computed, where the computing is based on the gradient sensor data and the translational data.

Abstract: One embodiment relates to a method of wavefield regularization for geophysical data acquisition of seismic geophysical data. Measured traces, are obtained from an array of sensors. For each grid point on a processing grid, best-fitting traces of the measured traces are found. Using the best-fitting traces, spectral amplitudes of down-going and up-going wavefields are computed. The down-going and up-going wavefields are subsequently transformed to an output grid in a space-time domain. Another embodiment relates to an apparatus for wavefield regularization of geophysical data acquisition. Other embodiments, aspects and features are also disclosed.

Abstract: A technique includes towing at least one seismic source in connection with a survey of a structure; and operating the seismic source(s) to fire shots, where each shot is associated with a frequency sweep. The technique includes varying phases of the frequency sweeps from shot to shot according to a predetermined phase sequence to allow noise in an energy sensed by seismic sensors to be attenuated.

Abstract: A workflow is presented that facilitates defining geocontextual information as a set of rules for multiple seismic attributes. Modeling algorithms may be employed that facilitate analysis of multiple seismic attributes to find candidate regions that are most likely to satisfy the set of rules. These candidates may then be sorted based on how well they represent the geocontextual information.

Abstract: The present disclosure provides a system and method for inferring one or more physical property parameters of a sub-surface media by inverting converted wave data acquired during a seismic survey. Composite seismic traces are generated at a plurality of survey azimuths (step 609). These composite traces are composed such that their amplitudes are free of effects of subsurface anisotropy. At least one of the generated composite seismic traces is then inverted by isotropic inversion to determine a property parameter of the subsurface media (step 623).

Abstract: A method includes receiving data representing measurements acquired by seismic sensors in response to energy that is produced by shots of a seismic source. The energy that is produced by the seismic source for each shot includes a plurality of discrete frequencies of discrete frequency bands that are within a frequency range of interest and are separated by at least one excluded frequency or frequency band. The data may be processed to determine at least one characteristic of a geologic structure.

Abstract: Geologic information may be extracted from multiple offset stacks and/or angle stacks. Offset stacks and/or angle stacks may be received that represent energy that has propagated through a geologic volume of interest from energy sources to energy receivers. Attribute volumes associated with individual source-receiver offsets and/or source-receiver angles may be determined based on corresponding offset stacks and/or angle stacks. For individual offset stacks or angle stacks, corresponding sets of geologic features represented in the attribute volumes may be identified. The sets of geologic features corresponding to the different offset stacks and/or angle stacks to may be compared to determine discrepancies and/or similarities between the sets of geologic features corresponding to the different offset stacks and/or angle stacks. Stratigraphic interpretations, stratigraphic predictions, and/or other interpretations and/or predictions may be determined based on causes of the discrepancies and/or similarities.

Abstract: A method for calculating time-strains for two seismic data sets resulting from seismic exploration of the same subsurface structure uses selected subsets of data from the two seismic data sets to calculate time-shifts for each trace. A smooth function is fitted along each trace based on the calculated time-shifts a time derivative is applied to the smooth function to obtain time-strains along each trace.

Abstract: A device, medium and method for processing ghosted seismic data associated with a subsurface of the earth. The method includes receiving the ghosted seismic data; receiving an initial velocity model; computing, in a processor, gathers G and mirror gathers M based on the ghosted seismic data and the initial velocity model; and calculating residual moveout curves r for each gather.

Abstract: A system and method for processing seismic data on one or more co-processor devices that are operatively coupled to a host computing system via a communications channel. The compression of input data transmitted to the co-processor device and/or the size of the storage provided on the co-processor device may enhance the efficiency of the processing of the data on the peripheral device by obviating a bottleneck caused by the relatively slow transfer of data between the host computing system and the co-processor device or by the relatively slow transfer of data within the co-processor device between the co-processor information storage and the co-processor.

Abstract: In a first aspect, a method for use in a time lapse, marine seismic survey includes accessing a set of acquired, multicomponent seismic data; and interpolating a set of time lapse seismic data from the acquired seismic data. In other aspects, a program storage medium is encoded with instructions that, when executed by a computing device, perform the above method and a computing apparatus programmed to perform one or more of such methods.

Abstract: A method is disclosed for operating an oil pool based on a reservoir model gradually deformed by means of cosimulations. A map of a property of the pool is obtained by a stochastic simulation of a first random function. A correlation coefficient is chosen between the first random function and a second random function with an identical mean and covariance. The map is modified by a cosimulation of the two random functions by using the correlation coefficient. The correlation coefficient is modified and the cosimulation step is reiterated to deform the map and minimize a matching objective function. Finally, the pool is operated by implementing an operating scheme accounting for the deformed map.

Abstract: A method of measuring a parameter characteristic of a rock formation is provided, the method including the steps of obtaining crosswell electromagnetic signals between two wells and using an inversion of said signals to investigate or delineate the presence of a resistivity anomaly, such as brine in a low resistivity background, wherein the resistivity anomaly is assumed to be distributed as one or more bodies characterized by a limited number of geometrical parameters and the inversion is used to determine said geometrical parameters. The method can also be applied to determine the trajectory of an in-fill well to be drilled.

Abstract: A system for synchronizing components of a downhole system includes: a source assembly including a source clock; an electromagnetic source associated with the source assembly and configured to emit an electromagnetic signal into an earth formation at a transmission time; a receiver assembly including a receiver clock; an electromagnetic receiver associated with the receiver clock and configured to detect the electromagnetic signal; and a processor configured to identify a receipt time of the electromagnetic signal based on the receiver clock and adjust the receiver clock by comparing the transmission time to the receipt time.