G01V2210/52

Automatic image registration of multicomponent seismic data

A method is described that includes obtaining a multicomponent seismic data set for a subterranean region of interest and determining, using a computer processor, a PP stacked time-domain seismic image and a PS stacked time-domain seismic image from the multicomponent seismic data set. The method further includes transforming a recording-time axis of at least one of the PP stacked time-domain seismic image and the PS stacked time-domain seismic image to produce a pair of coarsely-registered PP and PS seismic images and filtering at least one of the pair to produce a pair of spectrally-matched PP and PS seismic images. Further, the method includes dynamically warping at least one of the pair of spectrally-matched PP and PS seismic images to produce a pair of fully-registered PP and PS seismic images.

METHODS AND SYSTEMS PERFORMING JOINT VVAz AND AVAz INVERSION
20190369279 · 2019-12-05 ·

Methods for seismic exploration of an underground formation including at least one anisotropic layer perform a joint velocity-variation-with-azimuth, VVAz, and amplitude-variation-with-azimuth, AVAz, inversion using the azimuthal angle stacks to obtain a structural representation of the underground formation. The structural representation is used to generate scenarios for exploiting resources in at least one layer of the underground formation.

Method for enhancing the resolution of a seismic image
10466379 · 2019-11-05 · ·

A method for enhancing a physical parameter map in a zone of a seismic image. The dip of points of the image is obtained. For one of these points, called second point, a correction factor of a physical parameter is obtained with a residual move-out algorithm from a common image gather. A first point is selected on a line substantially perpendicular to the dip at the second point. The selection involves at least one parameter among whether the difference between the dip at the second point and the dip at the first point is below a first preset value; and the spacing between the first and the second point is below a second preset value. An inversion algorithm gives a corrected interval value of the physical parameter to update the physical parameter map.

System and method for automatically correlating geologic tops

A system and method are provided for automatically correlating geologic tops. The system receives well logs from different well bores and one or more user seed picks identifying a well top to be correlated. Each of the seed picks is added to a priority queue ordered by each pick's confidence. User selected picks are assigned the highest level of confidence. The system performs correlation by selecting a window of well log data about a user's manual pick, selected from the top of the priority queue, and then finding the best optimal match with a corresponding window in a neighboring wellbore. That new pick is then estimated in the target well using a correlation function. A quality value and a confidence value may then be calculated for each pick using some correlation function, for example dynamic time warping, and added to the priority queue according to the confidence value. The system may be configured so that picks that fall below a preset quality or confidence value may be discarded and not added to the queue. The system may then move on to the next pick in the priority queue.

ESTIMATING INTERVAL ANISOTROPY PARAMETER FOR PRE-STACK DEPTH MIGRATION USING A LEAST-SQARES METHOD
20190235113 · 2019-08-01 ·

An apparatus and a method for estimating interval anellipticity parameter by inversing effective anellipticity parameter in the depth domain using a least-squares method. One embodiment of interval anellipticity parameter estimator includes: 1) an interface configured to receive seismic data and borehole information; 2) a depth convertor configured to obtain a function of depth of effective anisotropy parameter based on said borehole information; 3) an inverse transformer configured to set up said function of depth of effective anisotropy parameter as a least-squares fitting problem based on said P-wave data; and 4) an iterative solver configured to use iterative methods to solve said least-squares fitting problem and to obtain an anisotropy model containing interval anellipticity parameter.

Premigration deghosting for marine streamer data using a bootstrap approach in Tau-P domain
10324208 · 2019-06-18 · ·

Methods and systems for optimized receiver-based ghost filter generation are described. The optimized ghost filter self-determines its parameters based on an iterative calculation of recorded data transformed from a time-space domain to a Tau-P domain. An initial ghost filter prediction is made based on generating mirror data from the recorded data and using a least squares technique during a premigration stage.

Attenuation of multiple reflections

A method can include selecting a location associated with a seismic survey geometry; selecting a trace for the location where the trace is selected from one of a plurality of different types of traces that include real data traces, interpolated data traces and model data traces; generating a multiple model based at least in part on the selected trace; and adjusting seismic data based at least in part on the multiple model.

DE-ALIASED SOURCE SEPARATION METHOD

Methods are described for separating the unknown contributions of two or more sources from a commonly acquired aliased wave field signals including the determination of models with reduced support in the frequency-wavenumber domain which reconstruct the wave fields of independently-activated sources after a coordinate-transform of the acquired wave field data and/or in a coordinate-transformed domain.

ANISOTROPIC NMO CORRECTION AND ITS APPLICATION TO ATTENUATE NOISES IN VSP DATA
20180356549 · 2018-12-13 · ·

A method for performing a formation-related operation based on corrected vertical seismic profile (VSP) data of an earth formation includes performing a VSP survey and applying a normal moveout (NMO) correction equation to the survey data that is a function of source offset to wellhead. The method also includes solving the NMO correction equation using a simulated annealing algorithm having an object function that is a coherence coefficient of semblance analysis of an NMO corrected reflection event within a time window to provide NMO corrected data. The method further includes performing the formation-related operation at at least one of a location, a depth and a depth interval based on the VSP NMO corrected data.

COMPUTING AMPLITUDE INDEPENDENT GRADIENT FOR SEISMIC VELOCITY INVERSION IN A FREQUENCY DOMAIN
20180335530 · 2018-11-22 · ·

A method for computing amplitude independent gradient for seismic velocity inversion in a frequency domain includes receiving seismic data associated with a region. The region comprises one or more earth subsurface layers represented by a plurality of points, and each point is associated with a seismic velocity. Seismic velocities at the plurality of points are determined by iteratively updating the seismic velocities based on a plurality of gradient values, where each gradient value corresponds to a point and is determined by evaluating a gradient of an objective function at a location of the point. A seismic image of the one or more earth subsurface layers is displayed based on the determined seismic velocities.