An imaging method, device, equipment, medium and system of VTI medium

Abstract

The application obtains a point scattering model and a reverse time migration image of a VTI medium in a target area, wherein the VTI medium is a transverse isotropic medium with a vertical symmetry axis; determines a point spread function data volume of the VTI medium according to the point scattering model; converts the point spread function data volume and the reverse time migration image into a frequency wave number domain by using Fourier transform to obtain a wave number domain reverse time migration image block and a wave number domain point spread function data block; and determines a least square image of the VTI medium according to the wave number domain reverse time migration image block and the wave number domain point spread function data block. The VTI medium least square migration imaging is realized, the influence of anisotropy on the imaging positioning is corrected, the influence on the imaging position and amplitude is eliminated, and the imaging precision is improved.

Description

Technical Field

[0001] This invention belongs to the technical field of seismic data imaging, specifically relating to an imaging method, apparatus, device, medium, and system for VTI media. Background Technology

[0002] Least squares migration imaging, which iteratively estimates subsurface reflectivity models by matching seismic observation data, is currently the most accurate inversion imaging theory. The imaging domain least squares migration method, by calculating the point spread function and approximating the inverse Hessian operator, obtains the least squares migration result without a single iterative step, alleviating the algorithm's requirements for high-precision velocity and wavelet characteristics. It has demonstrated good application results in practical seismic data processing. Currently, this technology still focuses on high-precision imaging of isotropic media, with insufficient consideration for VTI (vertically anisotropic) media. Anisotropic parameters affect both the travel time and phase of seismic wave propagation; therefore, in regions with well-developed anisotropy, the development of imaging algorithms specifically for anisotropic media is essential. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention proposes an imaging method for VTI media. This application acquires a point scattering model and a reverse-time migration image of a VTI medium in a target region, wherein the VTI medium is a laterally isotropic medium perpendicular to the axis of symmetry in the target region. The point spread function data volume of the VTI medium is determined based on the point scattering model. The point spread function data volume and the reverse-time migration image are then transformed into the frequency-wavenumber domain using Fourier transform to obtain a wavenumber-domain reverse-time migration image block and a wavenumber-domain point spread function data block. Finally, a least-squares image of the VTI medium is determined based on the wavenumber-domain reverse-time migration image block and the wavenumber-domain point spread function data block. This achieves least-squares migration imaging of VTI media, corrects the influence of anisotropy on the structural imaging positioning, eliminates the influence on imaging position and amplitude, and improves imaging accuracy.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention includes four aspects.

[0005] In a first aspect, an imaging method for VTI media is provided, comprising acquiring a point scattering model and a reverse-time migration image of a VTI medium in a target region, wherein the VTI medium is a transversely isotropic medium with a vertically anisotropic medium perpendicular to the axis of symmetry in the target region; determining a point spread function data volume of the VTI medium based on the point scattering model; transforming the point spread function data volume and the reverse-time migration image to the frequency-wavenumber domain using Fourier transform to obtain a wavenumber-domain reverse-time migration image block and a wavenumber-domain point spread function data block; and determining a least-squares image of the VTI medium based on the wavenumber-domain reverse-time migration image block and the wavenumber-domain point spread function data block.

[0006] In some embodiments, determining the point spread function data volume of the VTI medium based on the point scattering model includes: acquiring the migration velocity corresponding to the reverse-time migration image and the anisotropy parameters of the VTI medium; performing reverse migration on the point scattering model based on the migration velocity and the anisotropy parameters to obtain a perturbed wave field; and reverse-time migration of the perturbed wave field into a point spread function data volume.

[0007] In some embodiments, the step of using Fourier transform to convert the point spread function data volume and the reverse-time offset image to the frequency-wavenumber domain to obtain wavenumber-domain reverse-time offset image blocks and wavenumber-domain point spread function data blocks includes: obtaining the model parameters of the point scattering model; dividing the point spread function data volume and the reverse-time offset image into regions according to the model parameters to obtain multiple point spread function data blocks and reverse-time offset image blocks; converting each point spread function data volume block into a wavenumber-domain point spread function data block through Fourier transform; and converting each reverse-time offset image block into a wavenumber-domain reverse-time offset image block through Fourier transform.

[0008] In some embodiments,

[0009] The step of determining the least squares image of the VTI medium based on the wavenumber domain reverse time-shifted image block and the wavenumber domain point spread function data block includes: performing high-dimensional spatial deconvolution on each wavenumber domain point spread function data block and the corresponding wavenumber domain reverse time-shifted image block to obtain a wavenumber domain least squares image block; performing Fourier transform on each wavenumber domain least squares image block to obtain the least squares image block; and merging multiple least squares image blocks to obtain the least squares image of the VTI medium.

[0010] In some embodiments, the step of inversely migrating the point scattering model according to the migration velocity and the anisotropy parameter to obtain the perturbation wave field includes: acquiring the acoustic seismic wave field of the target area; and inversely migrating the point scattering model according to the acoustic seismic wave field, the migration velocity, and the anisotropy parameter to obtain the perturbation wave field.

[0011] In some embodiments, the point scattering model is inversely migrated based on the acoustic seismic wave field, the migration velocity, and the anisotropy parameter to obtain the perturbation wave field, using the following formula: In the formula, P and Q are the acoustic and seismic wave fields, ε and δ are anisotropic parameters, d represents the disturbance term, and v p dp represents the offset velocity, dv represents the perturbation wave field. pThe values ​​represent the disturbance parameters, where x represents the x-axis direction, y represents the y-axis direction, z represents the z-axis direction, and t represents the time axis direction.

[0012] In some embodiments, the high-dimensional spatial deconvolution of multiple wavenumber domain point spread function data blocks and multiple wavenumber domain reverse time-shifted image blocks is performed according to the following formula to obtain wavenumber domain least squares image blocks: Represents a wavenumber-domain time-shifted image block. This represents a data block of the point spread function in the wavenumber domain. Represents a least-squares image block in the wavenumber domain, where α is the regularization factor, and is... 5% of the maximum value.

[0013] Secondly, this application proposes an imaging device for VTI media, comprising: a first acquisition module for acquiring a point scattering model and a reverse-time migration image of a VTI medium in a target region, wherein the VTI medium is a transversely isotropic medium with a vertically anisotropic medium perpendicular to the axis of symmetry in the target region; a first determination module for determining a point spread function data volume of the VTI medium based on the point scattering model; a first execution module for converting the point spread function data volume and the reverse-time migration image to the frequency-wavenumber domain using Fourier transform to obtain a wavenumber-domain reverse-time migration image block and a wavenumber-domain point spread function data block; and a second determination module for determining a least-squares image of the VTI medium based on the wavenumber-domain reverse-time migration image block and the wavenumber-domain point spread function data block.

[0014] Thirdly, this application proposes an electronic device comprising: a memory and a processor, wherein the memory stores a computer program that, when executed by the processor, performs the method described in the first aspect.

[0015] Fourthly, this application proposes a storage medium storing a computer program that can be executed by one or more processors, the computer program being able to implement the method described in the first aspect.

[0016] The beneficial effects of this invention are as follows: This application obtains a point scattering model and a reverse-time migration image of a VTI medium in a target region, wherein the VTI medium is a laterally isotropic medium with a vertical axis of symmetry in the target region; determines the point spread function data volume of the VTI medium based on the point scattering model; uses Fourier transform to transfer the point spread function data volume and the reverse-time migration image to the frequency-wavenumber domain, obtaining a wavenumber-domain reverse-time migration image block and a wavenumber-domain point spread function data block; and determines the least-squares image of the VTI medium based on the wavenumber-domain reverse-time migration image block and the wavenumber-domain point spread function data block. This achieves least-squares migration imaging of the VTI medium, corrects the influence of anisotropy on the structural imaging positioning, eliminates the influence on imaging position and amplitude, and improves imaging accuracy. Attached Figure Description

[0017] The scope of this disclosure can be better understood by reading the following detailed description of exemplary embodiments in conjunction with the accompanying drawings. The accompanying drawings are:

[0018] Figure 1 An overall flowchart of an imaging method for VTI media provided in an embodiment of this application;

[0019] Figure 2 This is a structural block diagram of an imaging device using VTI media, provided as an embodiment of this application. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. The described embodiments should not be regarded as limitations on this application. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] In the following description, references are made to “some embodiments,” which describe a subset of all possible embodiments. However, it is understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0022] If the application documents contain similar descriptions such as "first, second, third", the following explanation shall be added: In the following description, the terms "first, second, third" are used only to distinguish similar objects and do not represent a specific order of objects. It is understood that "first, second, third" may be interchanged in a specific order or sequence where permitted, so that the embodiments of this application described herein can be implemented in an order other than that illustrated or described herein.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0024] Example 1:

[0025] Least squares migration imaging, which iteratively estimates subsurface reflectivity models by matching seismic observation data, is currently the most accurate inversion imaging theory. The imaging domain least squares migration method, by calculating the point spread function and approximating the inverse Hessian operator, obtains the least squares migration result without a single iterative step, alleviating the algorithm's requirements for high-precision velocity and wavelet characteristics. It has demonstrated good application results in practical seismic data processing. Currently, this technology still focuses on high-precision imaging of isotropic media, with insufficient consideration for VTI (vertically anisotropic) media. Anisotropic parameters affect both the travel time and phase of seismic wave propagation; therefore, in regions with well-developed anisotropy, the development of imaging algorithms specifically for anisotropic media is essential.

[0026] To address the problems existing in the current technology, such as Figure 1 As shown, this application provides an imaging method for VTI media, which is applied to an electronic device, such as a server, mobile terminal, computer, or cloud platform. The functions implemented by the device data processing provided in this application embodiment can be achieved by the processor of the electronic device calling program code, wherein the program code can be stored in a computer storage medium. The VTI media imaging method includes:

[0027] Step S1: Obtain the point scattering model and reverse time-shifted image of the VTI medium in the target region, wherein the VTI medium is a transversely isotropic medium with a vertical axis of symmetry in the target region.

[0028] Reverse-time migration imaging is obtained by migrating the anisotropic parameters of the VTI medium in reverse time at a preset migration rate. The point scattering model is obtained by uniformly and sparsely sampling the seismic data of the target area.

[0029] Step S2: Determine the point spread function data volume of the VTI medium based on the point scattering model.

[0030] In some embodiments, step S2, "determining the point spread function data volume of the VTI medium based on the point scattering model," includes:

[0031] Step S21: Obtain the offset velocity corresponding to the reverse time offset image and the anisotropy parameters of the VTI medium.

[0032] Step S22: The point scattering model is reverse-shifted according to the offset velocity and the anisotropy parameters to obtain the perturbed wave field.

[0033] In some embodiments, step S22, "reverse-migrating the point scattering model according to the offset velocity and the anisotropy parameter to obtain the perturbed wave field," includes:

[0034] Step S221: Obtain the acoustic seismic wave field of the target area.

[0035] Step S222: The point scattering model is reverse-migrated according to the acoustic seismic wave field, the migration velocity, and the anisotropy parameters to obtain the perturbation wave field.

[0036] In some embodiments, step S222 is implemented by the following formula:

[0037]

[0038] In the formula, P and Q are the acoustic and seismic wave fields, ε and δ are anisotropic parameters, d represents the disturbance term, and v p dp represents the offset velocity, dv represents the perturbation wave field. p The values ​​represent the disturbance parameters, where x represents the x-axis direction, y represents the y-axis direction, z represents the z-axis direction, and t represents the time axis direction.

[0039] Step S23: The perturbation wave field is offset in reverse time into a point spread function data volume.

[0040] Since the point spread function data volume cannot be obtained directly from the point scattering model, it is necessary to perform reverse migration on the point spread model through the acoustic migration equation to convert the point spread model into waveform data, namely the perturbation wave field in this application. Then, the perturbation wave field is reverse-time migrated to obtain the point spread function data volume that can be processed.

[0041] Step S3: Use Fourier transform to transfer the point spread function data volume and the reverse time offset image to the frequency wavenumber domain to obtain a wavenumber domain reverse time offset image block and a wavenumber domain point spread function data block.

[0042] Since the obtained reverse-time migrated image and point spread function data volume are in the time domain, it is inconvenient to fit them. Therefore, in this application, it is necessary to convert them to the wavenumber domain to obtain the wavenumber domain reverse-time migrated image block and the wavenumber domain point spread function data block.

[0043] Therefore, in some embodiments, step S3, "using Fourier transform to transfer the point spread function data volume and the reverse time-shifted image to the frequency wavenumber domain, to obtain a wavenumber domain reverse time-shifted image block and a wavenumber domain point spread function data block," includes:

[0044] Step S31: Obtain the model parameters of the point scattering model.

[0045] Step S32: Divide the point spread function data volume and the reverse time-shifted image into regions according to the model parameters to obtain multiple point spread function data blocks and reverse time-shifted image blocks.

[0046] Step S33: Convert each of the point spread function data blocks into wavenumber domain point spread function data blocks through Fourier transform.

[0047] Step S34: Convert each of the reverse time-shifted image blocks into wavenumber domain reverse time-shifted image blocks through Fourier transform.

[0048] Since the point scattering model is obtained through uniform sparse sampling, meaningful data in the point spread function (PSF) data volume obtained from the PSF model are discontinuous. To improve the accuracy of the least squares image, the PSF data volume needs to be divided into regions. During region division, to ensure that the data volume in each region is meaningful, the model parameters of the point scattering module need to be obtained, and then region division is performed based on these parameters. Correspondingly, since the least squares image needs to be determined using the reverse-time migration image and the PSF data volume, the reverse-time migration image also needs to be divided into regions. That is, there is a regional correspondence between the obtained PSF data blocks and the reverse-time migration image blocks.

[0049] Then, each point spread function data block and reverse time-shifted image block is subjected to a Fourier transform to obtain the corresponding wavenumber domain point spread function data block and wavenumber domain reverse time-shifted image block. Since the wavenumber domain point spread function data block is derived from a single point spread function data block, it is essentially a single data block. Similarly, the wavenumber domain reverse time-shifted image block is also a single data block, so ultimately multiple wavenumber domain point spread function data blocks and wavenumber domain reverse time-shifted image blocks will be obtained.

[0050] Step S4: Determine the least squares image of the VTI medium based on the wavenumber domain reverse time offset image block and the wavenumber domain point spread function data block.

[0051] In some embodiments, step S4, "determining the least squares image of the VTI medium based on the wavenumber domain reverse time-shifted image block and the wavenumber domain point spread function data block," includes:

[0052] Step S41: Perform high-dimensional spatial deconvolution on each wavenumber domain point spread function data block and the corresponding wavenumber domain reverse time-shifted image block to obtain a wavenumber domain least squares image block.

[0053] In some embodiments, step S41 is implemented by the following formula:

[0054]

[0055] Indicates the wavenumber domain counter-time shift. This represents a data block of the point spread function in the wavenumber domain. Represents a least-squares image block in the wavenumber domain, where α is the regularization factor, and is... 5% of the maximum value.

[0056] Step S42: Obtain the least squares image block by performing a Fourier transform on each of the wavenumber domain least squares image blocks.

[0057] Step S43: Merge multiple least-squares image blocks to obtain the least-squares image of the VTI medium.

[0058] Since the point spread data volume and the reverse time-shifted image have already been divided into regions, multiple wavenumber domain point spread data blocks and wavenumber domain reverse time-shifted image blocks are obtained. Therefore, when determining the least squares image, it is necessary to first perform high-dimensional spatial deconvolution on each wavenumber domain point spread data block and the reverse time-shifted image block belonging to the same region as the wavenumber domain point spread data block. Here, "same region" refers to being in the same region in the region division. Since the high-dimensional spatial deconvolution uses wavenumber domain data, and all of them are data blocks, the result is also a wavenumber domain least squares image block. Therefore, there are multiple wavenumber domain least squares image blocks at this time.

[0059] Then, a Fourier transform is performed on each wavenumber domain least squares image block to obtain multiple time-domain least squares images. Finally, the multiple time-domain least squares images are fused to obtain the least squares image of the VTI medium.

[0060] This application achieves least-squares migration imaging of VTI media by acquiring a point scattering model and a reverse-time migration image of a VTI medium in a target region, wherein the VTI medium is a laterally isotropic medium with a vertical axis of symmetry in the target region; determining the point spread function data volume of the VTI medium based on the point scattering model; using Fourier transform to transfer the point spread function data volume and the reverse-time migration image to the frequency-wavenumber domain, obtaining a wavenumber-domain reverse-time migration image block and a wavenumber-domain point spread function data block; and determining the least-squares image of the VTI medium based on the wavenumber-domain reverse-time migration image block and the wavenumber-domain point spread function data block. This realizes least-squares migration imaging of VTI media, corrects the influence of anisotropy on the structural imaging positioning, eliminates the influence on imaging position and amplitude, and improves imaging accuracy.

[0061] Example 2:

[0062] Based on the foregoing embodiments, this application provides an imaging device for VTI media. The various modules and units included in the device can be implemented by a processor in a computer device; of course, they can also be implemented by specific logic circuits. In the implementation process, the processor can be a central processing unit (CPU), a microprocessor unit (MPU), a digital signal processor (DSP), or a field programmable gate array (FPGA), etc.

[0063] like Figure 2 As shown, an imaging device for VTI media includes: a first acquisition module 1, a first determination module 2, a first execution module 3, and a second execution module 4.

[0064] The first acquisition module 1 is used to acquire the point scattering model and reverse-time migration image of the VTI medium in the target area, wherein the VTI medium is a transversely isotropic medium with a vertical axis of symmetry in the target area. The first determination module 2 is used to determine the point spread function data volume of the VTI medium based on the point scattering model. The first execution module 3 is used to transform the point spread function data volume and the reverse-time migration image into the frequency-wavenumber domain using Fourier transform, to obtain a wavenumber-domain reverse-time migration image block and a wavenumber-domain point spread function data block. The second determination module is used to determine the least-squares image of the VTI medium based on the wavenumber-domain reverse-time migration image block and the wavenumber-domain point spread function data block.

[0065] In some embodiments, the first determining module 2 includes: a second obtaining module, a third execution module, and a fourth execution module.

[0066] The second acquisition module is used to acquire the migration velocity corresponding to the reverse-time migration image and the anisotropy parameters of the VTI medium. The third execution module is used to reverse-migrate the point scattering model according to the migration velocity and the anisotropy parameters to obtain the perturbed wave field. The fourth execution module is used to reverse-time migrate the perturbed wave field into a point spread function data volume.

[0067] In some embodiments, the first execution module 3 includes: a third acquisition module, a fifth execution module, a sixth execution module, and a seventh execution module.

[0068] The third acquisition module is used to acquire the model parameters of the point scattering model. The fifth execution module is used to divide the point spread function data volume and the reverse time-shifted image into regional blocks according to the model parameters, resulting in multiple point spread function data blocks and reverse time-shifted image blocks. The sixth execution module is used to convert each point spread function data block into a wavenumber domain point spread function data block through a Fourier transform. The seventh execution module is used to convert each reverse time-shifted image block into a wavenumber domain reverse time-shifted image block through a Fourier transform.

[0069] In some embodiments, the second execution module 4 includes an eighth execution module, a ninth execution module, and a tenth execution module.

[0070] The eighth execution module performs high-dimensional spatial deconvolution on each wavenumber domain point spread function data block and the corresponding wavenumber domain reverse time-shifted image block to obtain a wavenumber domain least squares image block. The ninth execution module performs Fourier transform on each wavenumber domain least squares image block to obtain the least squares image block. The tenth execution module merges multiple least squares image blocks to obtain the least squares image of the VTI medium.

[0071] In some embodiments, the third execution module includes a fourth acquisition module and an eleventh execution module.

[0072] The fifth acquisition module is used to acquire the acoustic seismic wavefield of the target area. The eleventh execution module is used to perform inverse migration of the point scattering model based on the acoustic seismic wavefield, the migration velocity, and the anisotropy parameters to obtain the perturbation wavefield.

[0073] The various modules in the aforementioned VTI medium imaging device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of the device in hardware form or independently of it, or stored in the memory of the processing device in software form, so that the processor can call and execute the operations corresponding to each module. It should be noted that the module division in this embodiment is illustrative and only represents a logical functional division; in actual implementation, there may be other division methods.

[0074] Example 3:

[0075] The third aspect provides an electronic device including a storage device and a processor, the storage device storing a computer program, the processor executing the computer program to implement the steps of an imaging method for a VTI medium.

[0076] Example 4:

[0077] The fourth aspect provides a storage medium storing a computer program that can be executed by one or more processors, the computer program being able to implement the steps of any of the imaging methods for a VTI medium in the first aspect.

[0078] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the methods described above. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical storage, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0079] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of this application. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It should be understood that in the various embodiments of this application, the sequence numbers of the above-described processes do not imply a sequential order of execution; the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application. The sequence numbers of the above-described embodiments are merely descriptive and do not represent the superiority or inferiority of the embodiments.

[0080] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0081] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods, such as: multiple units or components can be combined, or integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the various components shown or discussed can be through some interfaces, and the indirect coupling or communication connection between devices or units can be electrical, mechanical, or other forms.

[0082] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units. They may be located in one place or distributed across multiple network units. Some or all of the units may be selected to achieve the purpose of this embodiment according to actual needs.

[0083] In addition, each functional unit in the various embodiments of this application can be integrated into one processing unit, or each unit can be a separate unit, or two or more units can be integrated into one unit; the integrated unit can be implemented in hardware or in the form of hardware plus software functional units.

[0084] Those skilled in the art will understand that all or part of the steps of the above method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps of the above method embodiments. The aforementioned storage medium includes various media that can store program code, such as mobile storage devices, read-only memory (ROM), magnetic disks, or optical disks.

[0085] Alternatively, if the integrated units described above are implemented as software functional modules and sold or used as independent products, they can also be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of the embodiments of this application, or the parts that contribute to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a controller to execute all or part of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as mobile storage devices, ROMs, magnetic disks, or optical disks.

[0086] The above description is merely an embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An imaging method for VTI media, characterized in that, include: Obtain the point scattering model and reverse time migration image of the VTI medium in the target region, wherein the VTI medium is a transversely isotropic medium with a vertical axis of symmetry in the target region; The point scattering model mentioned above is obtained by uniformly and sparsely sampling the seismic data of the target area. The point diffusion function data volume of the VTI medium is determined based on the point scattering model. The step of determining the point spread function data volume of the VTI medium based on the point scattering model includes: Obtain the offset velocity corresponding to the reverse time offset image and the anisotropy parameters of the VTI medium; The point scattering model is reverse-migrated according to the offset velocity and the anisotropy parameters to obtain the perturbation wave field. The perturbation wave field is offset in reverse time into a point spread function data volume; The point spread function data volume and the reverse time-shifted image are transformed into the frequency wavenumber domain using Fourier transform to obtain a wavenumber domain reverse time-shifted image block and a wavenumber domain point spread function data block. The least-squares image of the VTI medium is determined based on the wavenumber domain reverse time-shifted image block and the wavenumber domain point spread function data block.

2. The method according to claim 1, characterized in that, The step of using Fourier transform to transfer the point spread function data volume and the reverse time-shifted image to the frequency wavenumber domain to obtain a wavenumber domain reverse time-shifted image block and a wavenumber domain point spread function data block includes: Obtain the model parameters of the point scattering model; Based on the model parameters, the point spread function data volume and the reverse time-shifted image are divided into regions to obtain multiple point spread function data blocks and reverse time-shifted image blocks; Each of the point spread function data blocks is converted into a wavenumber domain point spread function data block using a Fourier transform; Each of the reverse time-shifted image blocks is converted into a wavenumber domain reverse time-shifted image block through Fourier transform.

3. The method according to claim 2, characterized in that, The step of determining the least-squares image of the VTI medium based on the wavenumber domain reverse-time offset image block and the wavenumber domain point spread function data block includes: Each wavenumber domain point spread function data block and the corresponding wavenumber domain time-shifted image block are subjected to high-dimensional spatial deconvolution to obtain a wavenumber domain least squares image block. The least squares image block is obtained by performing a Fourier transform on each of the wavenumber domain least squares image blocks; The least squares image blocks are merged to obtain the least squares image of the VTI medium.

4. The method according to claim 1, characterized in that, The step of inversely migrating the point scattering model based on the migration velocity and the anisotropy parameters to obtain the perturbed wave field includes: Obtain the acoustic seismic wave field of the target area; The point scattering model is reverse-migrated based on the acoustic seismic wave field, the migration velocity, and the anisotropy parameters to obtain the perturbation wave field.

5. The method according to claim 4, characterized in that, The point scattering model is inversely migrated based on the acoustic seismic wave field, the migration velocity, and the anisotropic parameters to obtain the perturbation wave field: ； In the formula, and For acoustic seismic wave field, and It is anisotropy parameter. Indicates the disturbance term. Indicates the offset speed. Indicates the perturbation wave field. Indicates the disturbance parameter. Indicates the x-axis direction. Indicates the y-axis direction. Indicates the z-axis direction. Indicates the direction of the time axis.

6. The method according to claim 3, characterized in that, The following formula is used to perform high-dimensional spatial deconvolution on multiple wavenumber domain point spread function data blocks and multiple wavenumber domain reverse time-shifted image blocks to obtain wavenumber domain least squares image blocks: Represents a wavenumber-domain time-shifted image block. This represents a data block of the point spread function in the wavenumber domain. Represents the least squares image block in the wavenumber domain. As the regularization factor, 5% of the maximum value.

7. An imaging device for VTI media, characterized in that, include: The first acquisition module is used to acquire the point scattering model and reverse time migration image of the VTI medium in the target area, wherein the VTI medium is a transversely isotropic medium with a vertical axis of symmetry in the target area. The point scattering model mentioned above is obtained by uniformly and sparsely sampling the seismic data of the target area. The first determining module is used to determine the point diffusion function data volume of the VTI medium based on the point scattering model; The first determining module includes: a second acquiring module, a third execution module, and a fourth execution module; The second acquisition module is used to acquire the offset velocity corresponding to the reverse time offset image and the anisotropy parameters of the VTI medium; The third execution module is used to reverse offset the point scattering model according to the offset velocity and the anisotropy parameters to obtain the perturbation wave field. The fourth execution module is used to offset the disturbed wave field in reverse time into a point spread function data volume; The first execution module is used to use Fourier transform to transfer the point spread function data volume and the reverse time offset image to the frequency wavenumber domain to obtain a wavenumber domain reverse time offset image block and a wavenumber domain point spread function data block. The second determining module is used to determine the least squares image of the VTI medium based on the wavenumber domain reverse time-shifted image block and the wavenumber domain point spread function data block.

8. An electronic device, characterized in that, include: A memory and a processor, wherein the memory stores a computer program that, when executed by the processor, performs the method as described in any one of claims 1-6.

9. A storage medium, characterized in that, The computer program stored in the storage medium can be executed by one or more processors, and the computer program can be used to implement the method as described in any one of claims 1-6.

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