Azimuthal anisotropic first-arrival ray tracing method and apparatus, and device and medium

Abstract

An azimuthal anisotropic first-arrival ray tracing method, which belongs to the field of first-arrival ray tracing. The method comprises: performing grid discretization processing on an HTI medium to obtain an HTI rectangular region, wherein the HTI rectangular region comprises a plurality of rectangular units, and each rectangular unit comprises a plurality of rays (S101); determining the group angles and lengths of rays in a rectangular unit at a receiving point (S102); inputting, into a pre-constructed initial azimuthal anisotropy velocity model, preset work area data and the group angles of the rays corresponding to the receiving point, so as to obtain a ray group velocity of the rectangular unit at the receiving point (S103); determining the travel time of the rectangular unit at the receiving point on the basis of the ray group velocity of the rectangular unit at the receiving point and the lengths of the rays (S104); and on the basis of a wavefront scanning search algorithm, tracing a first-arrival ray path on the basis of the travel time of the rectangular unit at the receiving point (S105). Further provided are an azimuthal anisotropic first-arrival ray tracing apparatus, and a device and a medium.

Description

Azimuthal anisotropic first-arrival ray tracing method, device, equipment and medium Technical Field

[0001] The present invention relates to the field of first-arrival ray tracing, and in particular to a method for tracing first-arrival ray with azimuthally anisotropic first-arrival ray, a device for tracing first-arrival ray with azimuthally anisotropic top-arrival ray, an electronic device and a computer-readable storage medium. Background Art

[0002] With the continuous increase in exploration efforts, the exploration targets are getting deeper and deeper, the height difference in the work area is getting larger and larger, and the lateral changes in shallow velocity are becoming more and more dramatic; with the continuous development of new acquisition technologies, the proportion of three-dimensional seismic data collected with large offsets and wide azimuths is increasing.

[0003] The anisotropic characteristics are reflected in these data. In many work areas, it has been found that there are obvious differences in the shallow velocity models inverted from first arrivals at different azimuths. The differences in the low-velocity part are particularly obvious and directly affect the imaging effect.

[0004] However, in the existing technology, the ray path obtained only by isotropic first-arrival ray tracing cannot accurately characterize the characteristics of the azimuthally anisotropic velocity field, resulting in large differences in the results of tomographic inversion in different azimuths and an inability to better describe the near-surface velocity distribution.

[0005] How to better utilize large-offset, wide-azimuth seismic data to complete the anisotropy investigation and modeling of refraction waves, eliminate the influence of surface anisotropy, and establish a more accurate near-surface velocity model is an issue that needs to be addressed urgently.

[0006] Summary of the Invention

[0007] The purpose of the present invention is to provide a method, device, equipment and medium for tracing azimuthally anisotropic first arrival rays, so as to at least solve the problem that the existing technology cannot accurately characterize the characteristics of the azimuthally anisotropic velocity field.

[0008] In order to achieve the above object, the present invention provides, on the one hand, a method for tracing azimuthally anisotropic first arrival rays, the method comprising:

[0009] Performing grid discretization processing on the HTI medium to obtain an HTI rectangular area, wherein the HTI rectangular area includes a plurality of rectangular units, and each rectangular unit includes a plurality of rays;

[0010] Determine the group angle and length of each ray within the rectangular unit of the receiving point;

[0011] The preset work area data and the group angle of each ray corresponding to the receiving point are input into a pre-built azimuthally anisotropic velocity initial model to obtain the ray group velocity of the rectangular unit of the receiving point. The preset work area data includes: HTI medium azimuth angle, symmetry axis axis, HTI medium anisotropy parameter and vertical velocity;

[0012] Determine the travel time of the rectangular unit at the receiving point based on the ray group velocity and the length of each ray at the receiving point;

[0013] Based on the wavefront scanning search algorithm, the first arrival ray path is traced according to the travel time of the rectangular unit of the receiving point.

[0014] Preferably, based on a wavefront scanning search algorithm, the path of the first arrival ray is tracked according to the travel time of the rectangular unit of the receiving point, including:

[0015] Perform wavefront scanning on the HTI rectangular area and determine the minimum travel time of all rectangular cells based on the travel time of the rectangular cells at the receiving point;

[0016] Search for the first arrival ray path based on the minimum travel time of all rectangular cells.

[0017] Preferably, the method further comprises: constructing an initial azimuthal anisotropic velocity model, comprising:

[0018] Determine the anisotropic Thomsen parameters of VTI media;

[0019] Performing coordinate axis transformation on the HTI medium and the VTI medium to obtain a transformation result, wherein the transformation result includes: anisotropic Thomsen parameters of the HTI medium and a transformation relationship between the HTI medium and the VTI medium;

[0020] An initial azimuthal anisotropic velocity model is constructed based on the conversion results.

[0021] Preferably, the azimuthal anisotropic velocity initial model v g (ψ) is:

[0022] Where, v p is the vertical velocity, cosψ is the conversion formula between HTI medium and VTI medium, ε is the first anisotropy parameter of VTI medium, which is used to characterize the longitudinal anisotropy intensity, and δ is the second anisotropy parameter of VTI medium.

[0023] Preferably, the conversion relationship between the HTI medium and the VTI medium is: cosψ=sinθcos(α-φ);

[0024] Where φ is the axial direction of the symmetry axis, α is the azimuth angle of the HTI medium, and θ is the angle between the incident ray and the vertical direction.

[0025] Preferably, the anisotropic Thomsen parameters of the HTI medium include: a first anisotropic parameter of the HTI medium, and the calculation expression of the first anisotropic parameter of the HTI medium is:

[0026] Where, ε (V) is the first anisotropy parameter of the HTI medium, and ε is the first anisotropy parameter of the VTI medium.

[0027] Preferably, the anisotropic Thomsen parameter of the HTI medium further includes: a second anisotropic parameter of the HTI medium, and the calculation expression of the second anisotropic parameter of the HTI medium is:

[0028] Where, δ (V) is the second anisotropy parameter of HTI medium, ε is the first anisotropy parameter of VTI medium, δ is the second anisotropy parameter of VTI medium, and f is the frequency;

[0029] Where, f=1-(v s / v p ) 2 , where v s is the shear wave velocity, v p is the vertical velocity.

[0030] On the other hand, the present invention further provides an azimuthally anisotropic first-arrival ray tracing device for implementing the above-mentioned azimuthally anisotropic first-arrival ray tracing method, the device comprising:

[0031] a discrete processing module, configured to perform grid discrete processing on the HTI medium to obtain an HTI rectangular region, wherein the HTI rectangular region includes a plurality of rectangular units, and each rectangular unit includes a plurality of rays;

[0032] A ray determination module is used to determine the group angle and length of each ray within the rectangular unit of the receiving point;

[0033] A velocity determination module is configured to input preset work area data and the group angle of each ray corresponding to the receiving point into a pre-built azimuthally anisotropic velocity initial model to obtain the ray group velocity of the rectangular unit at the receiving point. The preset work area data includes: the HTI medium azimuth angle, the axial direction of the symmetry axis, the HTI medium anisotropy parameter, and the vertical velocity.

[0034] A travel time determination module, for determining the travel time of the rectangular unit at the receiving point based on the ray group velocity and the length of each ray of the rectangular unit at the receiving point;

[0035] The ray tracing module is used to trace the first arrival ray path according to the travel time of the rectangular unit of the receiving point based on the wavefront scanning search algorithm.

[0036] On the other hand, the present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and runnable on the processor, wherein the processor implements the above-mentioned azimuthal anisotropic first-arrival ray tracing method when executing the computer program.

[0037] On the other hand, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which implements the above-mentioned azimuthally anisotropic first-arrival ray tracing method when executed by a processor.

[0038] Through the above technical solution, the present invention has at least the following technical effects:

[0039] The present invention can improve the adaptability of the first-arrival wave ray tracing technology. In the acquisition area of ​​large offset and wide azimuth data, it has the characteristics of azimuthal anisotropy, can more accurately describe the ray path of the first-arrival wave, and plays a key role in the near-surface anisotropy modeling.

[0040] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following detailed description, they are used to explain the embodiments of the present invention, but do not constitute a limitation of the embodiments of the present invention. In the accompanying drawings:

[0042] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following detailed description, they are used to explain the embodiments of the present invention, but do not constitute a limitation of the embodiments of the present invention. In the accompanying drawings:

[0043] FIG1 is a flow chart of an azimuthally anisotropic first-arrival ray tracing method provided by one embodiment of the present invention;

[0044] FIG2 is a schematic diagram of an HTI rectangular area provided by one embodiment of the present invention;

[0045] FIG3 is a schematic diagram of a path from one node to another in a uniform medium within a HTI rectangular region provided by an embodiment of the present invention;

[0046] FIG4 is a block diagram of an azimuthally anisotropic first-arrival ray tracing device provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0047] The following describes the specific implementation of the embodiment of the present invention in detail with reference to the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the embodiment of the present invention and is not used to limit the embodiment of the present invention.

[0048] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the art to which the present invention belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions.

[0049] In the description of the embodiments of the present invention, technical terms such as "first" and "second" are used solely to distinguish between different objects and should not be understood to indicate or imply relative importance or to implicitly specify the quantity, specific order, or primary and secondary relationship of the technical features indicated. In the description of the embodiments of the present invention, "plurality" means more than two, unless otherwise specifically defined.

[0050] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute a separate or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0051] Example 1

[0052] FIG1 is a flow chart of an azimuthally anisotropic first-arrival ray tracing method provided by one embodiment of the present invention. As shown in FIG1 , this embodiment provides an azimuthally anisotropic first-arrival ray tracing method, the method comprising:

[0053] Step S101: performing grid discretization processing on the HTI medium to obtain an HTI rectangular area, wherein the HTI rectangular area includes a plurality of rectangular units, and each rectangular unit includes a plurality of rays.

[0054] In this embodiment, the HTI medium is discretized into (m*n*l) adjacent rectangular units of the same size through a grid, and the velocity is uniform in each unit, as shown in FIG2 and FIG3 .

[0055] In the subsequent azimuthal anisotropic ray tracing process, starting from a known travel time point (such as the source point), the minimum travel time and ray direction information are gradually calculated according to the Fermat principle; let Q be the set of known travel time points q, p be the unknown travel time point adjacent to it, t q , t pare the minimum travel times of points q and p, respectively, and t pq is the minimum travel time from q to p (local travel time), r is the position of the secondary source of p (the intersection of the ray passing through point p and the wavefront), then: {r=q:t p =min(t q +t pq )};

[0056] According to Huygens' principle, q only needs to traverse the boundaries of Q (i.e., wavefront points). When the minimum travel times of all neighboring wavefront points are found, these points become new wavefront points.

[0057] Step S102: Determine the group angle and length of each ray within the rectangular unit of the receiving point.

[0058] In Figure 3, the geometric relationship of the ray path at the receiving point can be used to calculate the group angle corresponding to the ray path The length of the ray is the length of the ray experienced in the current grid (the rectangular unit corresponding to the receiving point) Among them, s x is the projection length of the ray length s in the x-axis direction, s y is the projection length of the ray length s in the y-axis direction, s z is the projection length of the ray length s in the z-axis direction.

[0059] Step S103: Input the preset work area data and the group angle of each ray corresponding to the receiving point into the pre-built azimuthal anisotropic velocity initial model to obtain the ray group velocity of the rectangular unit of the receiving point; wherein the preset work area data includes: HTI medium azimuthal angle, symmetry axis axial direction, HTI medium anisotropy parameter and vertical velocity.

[0060] In this embodiment, the method further includes: constructing an initial azimuthal anisotropic velocity model, including:

[0061] Step a01: Determine the anisotropic Thomsen parameters of the VTI medium;

[0062] Step a02: performing coordinate axis transformation on the HTI medium and the VTI medium to obtain a transformation result, wherein the transformation result includes: anisotropic Thomsen parameters of the HTI medium and a transformation relationship between the HTI medium and the VTI medium;

[0063] Step a03: Construct an initial azimuthal anisotropic velocity model based on the conversion results.

[0064] Among them, the azimuthal anisotropic velocity initial model v g (ψ) is:

[0065] Where, vp is the vertical velocity, cosψ is the conversion formula between HTI medium and VTI medium, ε is the first anisotropy parameter of VTI medium, which is used to characterize the longitudinal anisotropy intensity, and δ is the second anisotropy parameter of VTI medium.

[0066] The conversion relationship between the HTI medium and the VTI medium is: cosψ=sinθcos(α-φ); (2)

[0067] Where φ is the axial direction of the symmetry axis, α is the azimuth angle of the HTI medium, and θ is the angle between the incident ray and the vertical direction.

[0068] The anisotropic Thomsen parameters of the HTI medium include: a first anisotropic parameter of the HTI medium, and the calculation expression of the first anisotropic parameter of the HTI medium is:

[0069] Where, ε (V) is the first anisotropy parameter of the HTI medium, and ε is the first anisotropy parameter of the VTI medium.

[0070] The anisotropic Thomsen parameter of the HTI medium further includes a second anisotropic parameter of the HTI medium. The calculation expression of the second anisotropic parameter of the HTI medium is:

[0071] Where, δ (V) is the second anisotropy parameter of HTI medium, ε is the first anisotropy parameter of VTI medium, δ is the second anisotropy parameter of VTI medium, and f is the frequency;

[0072] Where, f=1-(v s / v p ) 2 , where v s is the shear wave velocity, v p is the vertical velocity.

[0073] In this embodiment, the anisotropic parameters of the HTI medium include: the second anisotropic parameter of the HTI medium and the first anisotropic parameter of the HTI medium. Based on the actual working condition data of the receiving point, the preset working area data can be obtained, that is, the HTI medium azimuth angle, the axial direction of the symmetry axis, the anisotropic parameter of the HTI medium, and the vertical velocity.

[0074] When the anisotropy parameters of the HTI medium, the azimuth angle of the HTI medium, the axial direction of the symmetry axis, the anisotropy parameters of the HTI medium and the vertical velocity are known, the group angle θ corresponding to the ray path will be calculated. sAs θ, the group velocity of the current grid can be calculated according to formula (1). The group velocity of each ray in the same grid unit is the same.

[0075] Step S104: determining the travel time of the rectangular unit at the receiving point according to the ray group velocity of the rectangular unit at the receiving point and the length of each ray.

[0076] Therefore, according to the ray length experienced in the current grid (rectangular unit corresponding to the receiving point) Dividing by the group velocity of the current grid can be calculated according to formula (1), the travel time of all wavefront points on the current grid boundary can be obtained. Since the current grid takes into account the rectangular cells adjacent to the grid, the travel time of the wavefront neighbor corresponding to each wavefront point is the minimum travel time among the travel times of all wavefront points in the grid cell.

[0077] Step S105: Based on the wavefront scanning search algorithm, the first arrival ray path is tracked according to the travel time of the rectangular unit of the receiving point.

[0078] In this embodiment, based on the wavefront scanning search algorithm, the first arrival ray path is tracked according to the travel time of the rectangular unit of the receiving point, including:

[0079] Step b01: Perform wavefront scanning on the HTI rectangular area and determine the minimum travel time of all rectangular cells based on the travel time of the rectangular cells at the receiving point;

[0080] Step b02: Search for the first arrival ray path based on the minimum travel time of all rectangular cells.

[0081] The wavefront scanning of the HTI rectangular area is:

[0082] Assume the travel time of the source point (i.e., the excitation location in Figure 2) is zero, and the travel time of all nodes other than the source point is infinite. First, select a scan center O. A square centered at O ​​and with r as half its side is the scan square. Now, let r increase in steps of 1, gradually expanding across the entire HTI rectangular area. Nodes on the four boundaries of each scan square are considered wavefront points. For each wavefront point, calculate the minimum travel time of its neighboring wavefront points. Then, narrow the scan from the HTI rectangular area boundary toward the scan center, scanning from the outside inward to calculate the travel time and ray paths of the first arrival wave at all nodes.

[0083] When searching for the first-arrival ray path, since each rectangular unit has a certain wavefront point travel time and position on its edge, the ray path from any point to the source point can be calculated. If the receiving point is determined (i.e., the receiving position in Figure 2), the corresponding secondary source coordinates are found in sequence with the receiving point as the starting point until the source point ends. Since the minimum travel time is recorded for each secondary source coordinate, the searched path is the minimum travel time path, that is, the first-arrival ray path.

[0084] In this embodiment, based on the group velocity at any position and the first arrival ray path, the minimum travel time of any shot pair traveling through the anisotropic velocity field and anisotropic field path can be calculated, thus preparing data for anisotropic multi-parameter inversion.

[0085] This embodiment can improve the adaptability of the first-arrival wave ray tracing technology. For the near-surface with azimuthal anisotropy in the collection area of ​​large offset and wide azimuth data, it can more accurately describe the ray path of the first-arrival wave, and plays a key role in the near-surface anisotropy modeling.

[0086] Example 2

[0087] FIG4 is a block diagram of an azimuthally anisotropic first-arrival ray tracing device provided by one embodiment of the present invention. As shown in FIG4 , based on the same inventive concept as in Example 1, this embodiment further provides an azimuthally anisotropic first-arrival ray tracing device for implementing the azimuthally anisotropic first-arrival ray tracing method in Example 1. The device includes:

[0088] a discrete processing module, configured to perform grid discrete processing on the HTI medium to obtain an HTI rectangular region, wherein the HTI rectangular region includes a plurality of rectangular units, and each rectangular unit includes a plurality of rays;

[0089] A ray determination module is used to determine the group angle and length of each ray within the rectangular unit of the receiving point;

[0090] A velocity determination module is configured to input preset work area data and the group angle of each ray corresponding to the receiving point into a pre-built azimuthally anisotropic velocity initial model to obtain the ray group velocity of the rectangular unit at the receiving point. The preset work area data includes: the HTI medium azimuth angle, the axial direction of the symmetry axis, the HTI medium anisotropy parameter, and the vertical velocity.

[0091] A travel time determination module, for determining the travel time of the rectangular unit at the receiving point based on the ray group velocity and the length of each ray of the rectangular unit at the receiving point;

[0092] The ray tracing module is used to trace the first arrival ray path according to the travel time of the rectangular unit of the receiving point based on the wavefront scanning search algorithm.

[0093] Based on the same inventive concept as embodiment 1, this embodiment also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and runnable on the processor, wherein the processor implements the above-mentioned azimuthal anisotropic first-arrival ray tracing method when executing the computer program.

[0094] Based on the same inventive concept as in the first embodiment, this embodiment further provides a computer-readable storage medium storing a computer program, which implements the above-mentioned azimuthally anisotropic first-arrival ray tracing method when executed by a processor.

[0095] This embodiment can improve the adaptability of the first-arrival wave ray tracing technology. For the near-surface with azimuthal anisotropy in the collection area of ​​large offset and wide azimuth data, it can more accurately describe the ray path of the first-arrival wave, and plays a key role in the near-surface anisotropy modeling.

[0096] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0097] The present invention is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0098] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a product including an instruction device that implements the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0099] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0100] In a typical configuration, a computing device includes one or more processors (CPUs), input / output interfaces, network interfaces, and memory.

[0101] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0102] Computer-readable media includes permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media (transitory media), such as modulated data signals and carrier waves.

[0103] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0104] The above are merely embodiments of the present invention and are not intended to limit the present invention. It will be apparent to those skilled in the art that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are intended to be included within the scope of the claims of the present invention.

Claims

1. A method for tracing azimuthally anisotropic first-arrival rays, characterized in that: The method comprises: Performing grid discretization processing on the HTI medium to obtain an HTI rectangular area, wherein the HTI rectangular area includes a plurality of rectangular units, and each rectangular unit includes a plurality of rays; Determine the group angle and length of each ray within the rectangular unit of the receiving point; The preset work area data and the group angle of each ray corresponding to the receiving point are input into the pre-constructed azimuthal anisotropic velocity initial model to obtain the ray group velocity of the rectangular unit of the receiving point; wherein the preset work area data includes: HTI medium azimuth angle, symmetry axis axial direction, HTI medium anisotropy parameter and vertical velocity; Determine the travel time of the rectangular unit at the receiving point according to the ray group velocity of the rectangular unit at the receiving point and the length of each ray; Based on the wavefront scanning search algorithm, the first arrival ray path is traced according to the travel time of the rectangular unit of the receiving point.

2. The method according to claim 1, characterized in that Based on the wavefront scanning search algorithm, the first arrival ray path is tracked according to the travel time of the rectangular unit of the receiving point, including: Perform wavefront scanning on the HTI rectangular area and determine the minimum travel time of all rectangular units based on the travel time of the rectangular units at the receiving point; Search for the first arrival ray path based on the minimum travel time of all rectangular cells.

3. The method according to claim 1, characterized in that: The method further comprises: constructing an initial azimuthal anisotropic velocity model, comprising: Determine the anisotropic Thomsen parameters of VTI media; Performing coordinate axis conversion on the HTI medium and the VTI medium to obtain conversion results, wherein the conversion results include: anisotropic Thomsen parameters of the HTI medium and a conversion relationship between the HTI medium and the VTI medium; The initial model of azimuthal anisotropic velocity is constructed based on the conversion results.

4. The method according to claim 3, characterized in that: The initial model of azimuthal anisotropic velocity v g (ψ) is: In the formula, v p is the vertical velocity, cosψ is the conversion formula between HTI medium and VTI medium, ε is the first anisotropy parameter of VTI medium, which is used to characterize the longitudinal anisotropy intensity, and δ is the second anisotropy parameter of VTI medium.

5. The method according to claim 4, characterized in that The conversion relationship between the HTI medium and the VTI medium is: cosψ=sinθcos(α-φ); Where φ is the axial direction of the symmetry axis, α is the azimuth angle of the HTI medium, and θ is the angle between the incident ray and the vertical direction.

6. The method according to claim 4, characterized in that The anisotropic Thomsen parameters of the HTI medium include: a first anisotropic parameter of the HTI medium, and the calculation expression of the first anisotropic parameter of the HTI medium is: In the formula, ε (V) is the first anisotropy parameter of HTI medium, and ε is the first anisotropy parameter of VTI medium.

7. The method according to claim 6, characterized in that The anisotropic Thomsen parameter of the HTI medium also includes: a second anisotropic parameter of the HTI medium, and the calculation expression of the second anisotropic parameter of the HTI medium is: In the formula, δ (V) is the second anisotropy parameter of HTI medium, ε is the first anisotropy parameter of VTI medium, δ is the second anisotropy parameter of VTI medium, and f is the frequency; Where f = 1-(v s / v p ) 2 , where v s is the shear wave velocity, v p is the vertical speed.

8. An azimuthally anisotropic first-arrival ray tracing device, used to implement the azimuthally anisotropic first-arrival ray tracing method according to any one of claims 1 to 7, characterized in that: The device comprises: A discrete processing module, used for performing grid discrete processing on the HTI medium to obtain an HTI rectangular area, wherein the HTI rectangular area includes a plurality of rectangular units, and each rectangular unit includes a plurality of rays; A ray determination module, used to determine the group angle and length of each ray within the rectangular unit of the receiving point; The velocity determination module is used to input the preset work area data and the group angle of each ray corresponding to the receiving point into the pre-built azimuth anisotropic velocity initial model to obtain the ray group velocity of the rectangular unit of the receiving point; wherein the preset work area data includes: HTI medium azimuth angle, symmetry axis axial direction, HTI medium anisotropy parameter and vertical velocity; A travel time determination module, used to determine the travel time of the receiving point rectangular unit according to the ray group velocity of the receiving point rectangular unit and the length of each ray; The ray tracing module is used to trace the first arrival ray path according to the travel time of the rectangular unit of the receiving point based on the wavefront scanning search algorithm.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the azimuthal anisotropic first-arrival ray tracing method described in any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the azimuthal anisotropic first-arrival ray tracing method described in any one of claims 1 to 7 is implemented.

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