Patent classifications
G01V2210/56
Device and method for constrained wave-field separation
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.
Directional Q Compensation with Sparsity Constraints and Preconditioning
A method for directional Q compensation of seismic data may comprise calculating angle-dependent subsurface travel times; applying directional Q compensation to the prestack seismic data to obtain Q-compensated data in time-space domain, wherein the directional Q compensation is based on the angle-dependent subsurface travel times; and using the Q-compensated data to generate an image of the subsurface. Directional Q compensation may comprise determining an angle-dependent forward E operator and an angle-dependent adjoint E* operator using the angle-dependent subsurface travel times; and applying a sparse inversion algorithm using the angle-dependent operators to obtain a model of Q-compensated data. The angle-dependent operators may be preconditioned by introducing ghost and source effects in a wavelet matrix and a transpose of the wavelet matrix, respectively, such that applying a sparse inversion algorithm using the preconditioned angle-dependent operators is used to obtain a model of Q-compensated, deghosted data without source effects.
Deghosting with adaptive operators
Methods and apparatuses for processing marine seismic data with a process of combined deghosting and sparse -p transformation. The process is formulated as an optimization problem. The optimization problem has an objective function that is a weighted sum of two norms: one norm is an Lp norm of the differences between the modeled data and acquired survey wherein the modeled data are derived from a model and a set of adaptive filters; the other norm is an Lq norm of the model; and the optimization variables and solutions are the coefficients of the model and coefficients of the adaptive filters.
NOISE ATTENUATION
Noise can be attenuated in marine seismic data from a marine seismic survey. A first near-continuous measurement of a wavefield and a second near-continuous measurement of the wavefield recorded from a marine seismic survey can be equalized, a coherent portion of the equalized second near-continuous measurement can be collapsed, and a noise model can be derived. The noise model can be subtracted from the second near-continuous measurement.
OFFSHORE APPLICATION OF NON-UNIFORM OPTIMAL SAMPLING SURVEY DESIGN
Method for acquiring seismic data is described. The method includes obtaining undersampled seismic data acquired from a non-uniform sampling grid. Attenuating multiples from the undersampled seismic data.
Seismic data processing
Described herein are implementations of various technologies for a method for seismic data processing. The method may receive seismic data for a region of interest. The seismic data may be acquired in a seismic survey. The method may receive a summation that is based on a particle motion velocity component of a seismic wavefield in the vertical direction and the pressure component of the seismic wavefield. The method may predict an upgoing pressure component of the seismic wavefield for the region of interest. The method may compare the predicted upgoing pressure component to the received seismic data that corresponds to the received summation. The method may update the predicted upgoing pressure component based on the comparison. The method may use the updated upgoing pressure component in hydrocarbon exploration or production for the region of interest.
Method for generating multiple free seismic images
A method, including: storing, in a computer storage device, geophysical seismic data that has been separated into a multiple-free component and a multiple contaminated component; performing, with a processor, a first full wavefield inversion process on the multiple-free component of the seismic data, wherein a first subsurface physical property model is generated; determining, with a processor, an extended target reflectivity, wherein the extended target reflectivity includes a reflectivity for each of a plurality of shots; separately performing, with a processor, a second full wavefield inversion process with the multiple contaminated component of the seismic data for each of the plurality of shots using the reflectivity corresponding to each of the plurality of shots, wherein a second subsurface physical property model is generated; and generating, with a processor, multiple-free final subsurface physical property model by combining the first subsurface physical property model and the second subsurface physical property model.
Method for predicting multiples in survey data
A method includes receiving a seismic dataset from a survey, wherein the seismic dataset represents a portion of a subsurface geological formation and includes primary and multiple data. The method further includes the steps of conditioning the seismic dataset and estimating a model of the multiple data in the conditioned seismic dataset based on a user-defined parameter to derive a primary data set. Further, the method includes the steps of computing a velocity model from the primary data set using the user-defined parameter and updating the estimated multiple model based at least on a modification of the user-defined parameter. In addition, the method includes the steps of recomputing the primary data and the velocity model based on the modified user-defined parameter and generating an image of the primary data.
ESTIMATING A TIME VARIANT SIGNAL REPRESENTING A SEISMIC SOURCE
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.
Crosstalk attenuation for seismic imaging
Crosstalk attenuation for seismic imaging can include creation of a seismic image based on seismic data including multiples. The seismic image can include causal crosstalk and anti-causal crosstalk. Causal crosstalk and anti-causal crosstalk can be predicted based on the seismic data. The predicted causal crosstalk and the predicted anti-causal crosstalk can be attenuated from the seismic image.