21 results about "Exploration geophysics" patented technology

The invention discloses an elastic reverse time migration imaging method based on deviatoric stress characterization, and relates to the technical field of exploration geophysics. Deviatoric stress is introduced into a conventional elastic wave equation, and a speed-deviatoric stress elastic wave equation describing stress propagation characteristics is obtained through derivation; based on Hooke's law, P wave contribution in total partial strain is removed through partial strain decomposition, decoupling of P-S wave stress components is achieved, and correctness of amplitude, phase and physical unit of a decoupling wave field is guaranteed; and then a joint imaging condition with the average stress as a seismic source wave field and the multi-stress component as a receiving wave field is constructed, PP waves are subjected to normalization superposition through the average stress and the deviatoric stress, and PS waves are subjected to shear stress imaging. According to the method, the sensitivity to heterogeneity and local stress variation of underground media can be remarkably improved, P-S wave crosstalk and imaging noise are effectively eliminated, the imaging precision and resolution of a complex geologic structure are greatly improved, and a reliable technical means is provided for high-precision seismic exploration of complex oil and gas reservoirs.

The invention discloses a seabed node transverse wave leakage suppression method, system, medium and equipment based on Uform, and belongs to the field of exploration geophysics, and the method comprises the steps of multi-component data preprocessing, radial component acquisition, Uform network model and data set construction, network training optimization and actual data application. The invention further provides a system, a medium and equipment for operating the method. According to the method, the transverse wave leakage noise in the Z component can be effectively predicted and removed, and the signal-to-noise ratio and interpretation reliability of an imaging profile are improved. A global dependency relationship among different positions of an input sequence is modeled through a self-attention mechanism, and the extraction and prediction precision of a shear wave leakage model is improved; in the data set construction stage, a horizontal component is rotated to a radial tangential component, fusion utilization of information in the X direction and the Y direction is achieved, the problem of representation inconsistency caused by the coupling difference of the X components of different detection points is solved, and the description capacity and stability of the transverse wave leakage form are enhanced.

The present application belongs to the field of exploration geophysics, and particularly relates to a transient electromagnetic perspective detection method for water-bearing area in a coal mining face. Measurement points are arranged in two roadways of the coal mining face. A transmitting wire frame is fixed at a first point of a transmitting roadway for transmission, and a receiving wire frame receives at different positions in a certain range of the opposite roadway. The transmitter and the receiver are consistent in time and can synchronously collect. After the first point transmits, the transmitting coil is moved to a next position for transmission at a second point. Similarly, the receiving coil can receive in a certain range of the opposite roadway. After the second point transmits, the third point transmits, and so on until the transmission of the whole roadway is completed. The transmitting roadway and the receiving roadway are exchanged, and the above steps are repeated until the whole face is detected, and then inversion calculation is performed. The present application can solve the problems of low positioning accuracy of water-bearing abnormal body and inaccurate abnormal shape discrimination of the existing mine transient electromagnetic method.

This disclosure pertains to the field of exploration geophysics and presents a method and system for combined active and passive source reverse time migration imaging of metallic minerals. The method includes: performing time difference correction on active and passive source seismic data from the same subsurface structure; performing wavefield separation on the time-aligned active and passive source seismic data to reconstruct the P-wave and S-wave fields of the active source and the passive source; performing active and passive source wavefield extrapolation based on the two-way wave equation; obtaining active and passive source PS-converted wave imaging results using cross-correlation imaging conditions; and performing weighted superposition and fusion to obtain the combined active and passive source imaging results. This disclosure leverages the high resolution advantage of active sources combined with the deep detection capability of passive sources, replacing the limitations of single-source detection and achieving high-precision deep reverse time migration imaging.

The invention discloses a meshless seismic wave forward modeling method based on a difference numerical method and related equipment, and belongs to the field of exploration geophysics. According to the method, flexible mesh generation is carried out based on an undulating surface seismic wave speed model, a surface interface is completely fitted, and a high-precision difference coefficient set is obtained without manually selecting deformation parameters; by adding a filter related to a second-order time item in a two-dimensional scalar time domain acoustic wave equation, the robustness and accuracy of numerical simulation are effectively improved, so that a high-precision and stable seismic wave numerical simulation result is obtained, the precision and stability of seismic data processing can be effectively improved by utilizing the method, and the seismic data processing efficiency is improved. The method provides solid technical support for loess tableland seismic wave forward modeling, and has important practical significance for evaluating the influence of the earth surface effect on exploration data in the loess tableland, improving the accuracy and reliability of the exploration data, analyzing the physical properties and change rules of underground media and simulating the physical properties and seismic wave propagation conditions of underground structures.

The invention belongs to the technical field of exploration geophysics and seismic signal processing, and relates to a Rayleigh wave double-component fusion method and system based on model prediction. In order to solve the problem that a fusion decision depends on an empirical threshold and cannot quantitatively predict an effect, the method comprises the following steps: acquiring seismic data continuously acquired by a station pair in a target area; calculating the signal-to-noise ratio of the ZZ cross-correlation function and the signal-to-noise ratio of the RR cross-correlation function of each station pair; calculating the ratio of the signal-to-noise ratio of the RR cross-correlation function to the signal-to-noise ratio of the ZZ cross-correlation function of each station pair; calculating a similarity index according to the ratio; predicting a fusion gain by adopting a similarity index; and according to a comparison result of the prediction gain and a target threshold value, intelligently deciding whether to carry out double-component fusion, and outputting a final effective signal. According to the method, the fusion decision is improved from experience judgment to a computable and optimizable model driving process, the overall signal-to-noise ratio of the data can be stably and reliably improved, and the seismic data quality for imaging is directly improved.

This invention relates to the field of exploration geophysics and provides a method for reconstructing VSP data into ground seismic data. This method can reconstruct VSP data into ground seismic data, changing the type of the original seismic data. The reconstructed seismic data has a high signal-to-noise ratio. Furthermore, by performing joint data processing on the original VSP data and the reconstructed ground seismic data, the imaging accuracy of underground geological structures can be improved, and the imaging range of underground geological structures can be effectively expanded, resulting in high-quality imaging results.

The invention belongs to the technical field of exploration geophysics, and discloses a pure viscous sound forward modeling method and system. The method comprises the following steps: setting an observation system, and obtaining an initial model parameter field; performing grid division on the initial model parameter field to obtain a model parameter at each grid point; setting a high-precision pure viscous sound anisotropic wave equation, and constructing a high-precision wave field propagation operator; determining a pure viscous sound anisotropic wave equation coefficient based on the pure viscous sound anisotropic wave equation and the model parameter at each grid point; and calculating to obtain a longitudinal wave field value of each grid point by adopting the wave field propagation operator, the pure viscoacoustic anisotropy wave equation coefficient and the initial model parameter field. According to the method, the propagation process of waves in the complex underground medium can be simulated more accurately.

The invention discloses a time migration method for a three-dimensional pre-stack wave equation in an imaging ray domain, which relates to the technical field of exploration geophysics and comprises the following steps of: deducing a bidirectional acoustic wave equation in an imaging ray coordinate system based on a Riemann wave field extrapolation theory in a three-dimensional semi-orthogonal coordinate system; an equation is directly solved by adopting a finite difference method, extrapolation of a seismic source and a receiving end wave field is achieved, and errors caused by Green function approximation in a traditional migration method are avoided; and generating a pre-stack time migration result by applying a zero-lag cross-correlation imaging condition. Through first-order linear disturbance approximation, an accurate three-dimensional time-depth conversion partial differential equation set is simplified into an optimized layer stripping algorithm, and a corresponding equation suitable for a weak transverse velocity change medium is deduced. According to the invention, the working process of three-dimensional wave equation time migration is realized in an imaging ray coordinate system, and an accurate seismic imaging result is generated; two-dimensional plane hypothesis limitation is avoided, and high-precision imaging technical guarantee is provided for seismic data processing of a complex structure area.

The application discloses a kind of direct reverse-time migration imaging methods based on DAS acquisition strain rate data, it is related to the technical field of exploration geophysics, including s1, based on velocity-pressure wave equation and strain rate-velocity relationship establishes pressure-strain rate equation;S2, based on pressure-strain rate equation, obtains positive transmission wave field and reverse transmission wave field;S3, using cross-correlation imaging condition to positive transmission wave field and reverse transmission wave field are imaged, and imaging result I (x) is obtained;S4, the comprehensive illumination matrix of source and wave field of geophone is calculated;S5, the comprehensive illumination compensation of imaging result I (x) is obtained final imaging result I final (x).The application directly uses strain rate data for imaging, not only avoids the error caused by data conversion, significantly improves the fidelity of data and the accuracy of imaging, but also simplifies the data processing procedure.In addition, the method improves the illumination effect of deep underground area through comprehensive illumination strategy, so that the imaging result is clearer and more detailed.

The present specification relates to the technical field of exploration geophysics, and particularly relates to an anisotropic elastic wave decoupling method and device and computer equipment. The anisotropic elastic wave decoupling method comprises: determining a set of Thomson parameters included in an anisotropic model according to a received wave field decomposition request to be decomposed, the wave field decomposition request to be decomposed comprising a wave field to be decomposed; converting the set of Thomson parameters to obtain an initial set of elastic parameters; performing P-S wave velocity separation processing on the initial set of elastic parameters to obtain a target P-wave elastic parameter set and a target S-wave elastic parameter set; and substituting the target P-wave elastic parameter set and the target S-wave elastic parameter set into the anisotropic model to process the wave field to be decomposed to obtain a target P-wave matrix and a target S-wave matrix. The embodiments of the present specification simplify the P-S wave field decomposition process and reduce the calculation cost.

The application discloses a kind of seismic structural feature oriented geostatistical modeling methods, belong to exploration geophysics field;The method comprises: based on the prior information of geostatistics, the multivariate Gaussian prior distribution of underground parameter model is established;From seismic data, structural guidance information is extracted, including calculating gradient, constructing structural tensor and carrying out eigenvalue decomposition to obtain local dominant direction;Accordingly, a structure-guided constraint operator is constructed;Well logging data constraints are combined with structural constraints to form an observation system;The prior distribution is updated using Bayes' theorem to obtain a posterior distribution containing posterior mean and covariance.The application realizes reasonable interpolation along the trend of strata, improves the accuracy and structural consistency of geological modeling, and can quantitatively predict uncertainty.

The application discloses a kind of based on Uformer's seabed node transverse wave leakage suppression method, system, medium and equipment, belong to the field of exploration geophysics, the method includes multi-component data preprocessing, radial component acquisition, Uformer network model and dataset construction, network training optimization and actual data application;The application also provides the method system, medium and equipment of running described.The application can effectively predict and remove the transverse wave leakage noise in Z component, improve the signal-to-noise ratio and interpretation reliability of the imaging profile.By self-attention mechanism modeling, the global dependence relationship between different positions of input sequence is established, the extraction and prediction accuracy of the transverse wave leakage model is improved;In the dataset construction stage, the horizontal component is rotated to the radial tangent component, the fusion and utilization of X and Y direction information are realized, the inconsistency problem caused by the coupling difference of different geophones X component is reduced, and the description ability and stability of the transverse wave leakage form are enhanced.

The invention discloses a seismic structure feature-oriented geostatistics modeling method, and belongs to the field of exploration geophysics. The method comprises the following steps: establishing multivariate Gaussian prior distribution of an underground parameter model based on geostatistics prior information; extracting structure-oriented information from the seismic data, including calculating a gradient, constructing a structure tensor and performing eigenvalue decomposition to obtain a local dominant direction; constructing a structure-oriented constraint operator according to the structure-oriented constraint operator; the logging data constraint and the structure constraint are combined to form an observation system; and updating the prior distribution by using the Bayesian theorem to obtain posteriori distribution containing a posteriori mean value and a covariance. According to the method, reasonable interpolation along the stratigraphic direction is realized, the precision and the structure consistency of geological modeling are improved, and the uncertainty can be quantitatively predicted.

The invention relates to the technical field of exploration geophysics and artificial intelligence deep learning, and discloses a tight sandstone reservoir gas-bearing prediction method and device based on feature space guided modeling. The method comprises the following steps: establishing a supervised learning method, and predicting a general normal form of the gas-bearing property of the tight sandstone reservoir based on a pre-stack seismic trace set and a logging gas-bearing curve; establishing a feature space guide modeling method which comprises the following steps: performing preliminary gas-bearing prediction on a target work area by using a kNN method, and screening a high-probability kNN prediction result as pseudo training data; pre-training the CNN model by using the pseudo training data; and carrying out transfer learning optimization on the stable CNN model by utilizing an actual training sample to realize gas-bearing prediction of the tight sandstone reservoir. According to the technical scheme provided by the invention, the advantage of depiction capability of deep learning on a complex nonlinear relationship is brought into play, the mapping relationship between the seismic response and the gas content of the tight sandstone reservoir is clarified, and finally the prediction precision of the tight reservoir is improved.

The application discloses a high-speed rail seismic data wave field separation method and system using random Cadzow filtering, and belongs to the technical field of exploration geophysics. The method comprises the following steps: collecting seismic data of high-speed rail passing time; estimating seismic wave propagation velocity through Radon transformation; correcting the time difference of the same direction wave field event to obtain aligned data; dividing the aligned data into blocks and randomly rearranging; performing Fourier transformation on the rearranged data and constructing a Hankel matrix; performing SVD decomposition and low-rank reconstruction on the Hankel matrix; reconstructing the frequency domain data block through inverse Hankel operation; performing inverse Fourier transformation and recovering the channel sequence; and extracting and averaging the central channel to obtain unidirectional wave field data. The system comprises corresponding functional modules. The application can effectively separate the mixed wave field of the high-speed rail seismic source, improve the data signal-to-noise ratio, and provide a reliable data basis for underground imaging.

The invention belongs to the field of exploration geophysics, and relates to an active and passive source combined reverse time migration metal mine converted wave imaging method and system, and the method comprises the steps: carrying out the time difference correction of active source seismic data and passive source seismic data of a same underground structure; respectively carrying out wave field separation on the active source seismic data and the passive source seismic data after time alignment, and reconstructing a P-wave field and an S-wave field of the active source and a P-wave field and an S-wave field of the passive source; performing active source wave field extrapolation and passive source wave field extrapolation based on a two-way wave equation; obtaining an active source PS converted wave imaging result and a passive source PS converted wave imaging result by using a cross-correlation imaging condition; carrying out weighted superposition fusion to obtain an active and passive source combined imaging result; according to the invention, the high resolution advantage of an active source and the deep detection capability of a passive source are combined, the limitation of single-source detection is replaced, and high-precision deep reverse time migration imaging is realized.

This specification relates to the field of exploration geophysics, and more particularly to an anisotropic elastic wavefield decomposition method, apparatus, and computer equipment. The anisotropic elastic wavefield decomposition method includes processing the received source wavelet according to an anisotropic model to obtain an anisotropic elastic vector wavefield matrix; determining the scalar P-wave matrix and vector S-wave matrix based on the modified Helmholtz operator and the vector wavefield matrix; and performing anisotropic medium correction and vectorization processing on the scalar P-wave matrix and vector S-wave matrix to obtain the target vector P-wave matrix and target vector S-wave matrix corresponding to the anisotropic elastic wavefield. Using the embodiments in this specification, by processing the anisotropic elastic wavefield with the modified Helmholtz operator, and then performing anisotropic medium correction and vectorization processing, the calculation process is simplified and the computational cost is reduced.

This invention belongs to the field of exploration geophysics and discloses a wavefield simulation method based on a progressive autoregressive Fourier neural operator, comprising the following steps: S1. Constructing a neural operator model; S2. Training the model using a progressive sampling strategy, controlling the model's transition from ground truth supervision to autoregressive prediction; S3. Utilizing the trained model, through an autoregressive approach that recursively feeds back the current output as subsequent inputs, to achieve rapid inference of full-time series wavefield snapshots under an unknown velocity model. This invention overcomes the strict limitations of traditional numerical simulation methods on spatial and temporal sampling rates by combining a progressive autoregressive mechanism with operator learning. A specific sampling strategy ensures the numerical stability of the model in long-sequence inference, significantly improving the computational efficiency of wavefield forward modeling compared to traditional numerical simulation methods, and providing an efficient wavefield forward modeling engine for large-scale seismic data processing and full-waveform inversion.

The invention discloses an earthquake attenuation compensation method based on an angle domain common imaging point gather, and relates to the technical field of exploration geophysics, the method comprises the following steps: firstly, carrying out Dix inversion on a migration velocity model, solving an imaging ray domain wave equation by using a space eight-order time second-order staggered grid, and carrying out time migration by using a time consistency principle cross-correlation imaging condition; and an uplink wave field and a downlink wave field are separated in an imaging ray domain, and Hilbert transform is fused to construct an auxiliary vector, so that the oscillation defect of a traditional Poynting vector is thoroughly eliminated, and the high-fidelity ADCIGs is generated. The method has the beneficial effects that a brand new way is created for realizing stable Q field inversion and directional compensation in an angle domain, an angle-related absorption attenuation model can be constructed by utilizing high-precision incident angle information in ADCIGs, and the global averaging processing limitation of traditional inverse Q filtering is broken through.

The embodiment of the invention provides a tight sandstone rock physical modeling method and related equipment, and belongs to the technical field of rock exploration geophysics. The method comprises the following steps: acquiring core data, logging data, rock physical parameters and reservoir conditions; the rock physical parameters comprise mineral components, porosity and permeability; the reservoir conditions comprise formation temperature and formation pressure; calculating according to physical parameters of the rock through a VRH model to obtain a dry skeleton volume modulus and a dry skeleton shear modulus of the tight sandstone, and mixing the mixed fluid and the dry skeleton through an SCA model to obtain a static modulus of the saturated rock; and calculating according to the static modulus of the saturated rock through a BISQ model to obtain the velocity of the longitudinal and transverse waves. According to the embodiment of the invention, the reliability of predicting the seismic wave speed and attenuation can be improved, and a theoretical basis and calculation support are provided for unconventional reservoir seismic response analysis and rock physical parameter inversion.