Three-dimensional ground magnetic tensor rapid calculation method, device, equipment and medium

Abstract

The invention mainly relates to the technical field of geophysics and exploration, and provides a three-dimensional ground magnetic tensor rapid calculation method, device, equipment and medium, and the method comprises the steps: determining a target region of magnetic geological exploration and the size, shape and magnetic susceptibility distribution of anomalous bodies in the target region, and setting the observation height; constructing a target area model containing the anomalous body model, and performing three-dimensional grid division on the target area model containing the anomalous body model; setting the magnetic susceptibility distribution range of each layer of anomalous body model, and calculating the magnetization intensity of each layer of anomalous body model; calculating a kernel function coefficient matrix of each layer of anomalous body model by adopting a compression storage strategy; and obtaining a three-dimensional ground magnetic tensor at an observation height by adopting two-dimensional convolution of a kernel function coefficient matrix of each layer of anomalous body model calculated by two-dimensional fast Fourier transform and magnetization intensity. According to the invention, the discrete convolution time is further reduced on the premise of ensuring the calculation precision, and the rapid forward calculation of the three-dimensional ground magnetic tensor is realized.

Description

Technical Field

[0001] The present invention mainly relates to the technical field of geophysics and exploration technology, and in particular to a three-dimensional ground magnetic tensor fast calculation method, device, equipment and medium. Background Technique

[0002] Magnetic exploration is a relatively mature geophysical exploration method and has been widely used in the exploration of magnetite and associated minerals, oil and gas structures, and global-scale tectonic research. With the increase in exploration difficulty and the in-depth application of exploration methods, achieving refined inversion imaging and artificial interactive interpretation modeling has gradually become a research hotspot in magnetic exploration. Compared with magnetic anomalies and three magnetic field components, the magnetic tensor has higher resolution. With the development of magnetic tensor exploration technology, when conducting refined exploration for a given target area, there are often many observation points. Traditional magnetic tensor forward simulation methods have low accuracy, large memory occupation, and long calculation time. Therefore, fast forward simulation of magnetic gradient tensors becomes particularly important.

[0003] Currently, the commonly used fast forward methods for magnetic tensors mainly include two types: spatial domain methods and frequency domain methods. Spatial domain methods have high calculation accuracy, but the calculation amount increases exponentially with the increase in the number of grid division units, making it difficult to meet the requirements of refined inversion imaging and artificial interactive interpretation modeling; frequency domain methods, due to the use of fast Fourier transform, greatly improve the calculation efficiency, but due to the boundary oscillation effect of the fast Fourier transform, the further popularization and application of this method are limited.

[0004] Based on the above description, there is an urgent need to find a method for efficiently and accurately calculating the magnetic gradient tensor of abnormal bodies in the target area to solve the problems of low calculation efficiency, large memory consumption of spatial domain methods, and low calculation accuracy of frequency domain methods, and achieve the unity of accuracy and efficiency. Summary of the Invention

[0005] In view of the technical problems existing in the prior art, the present invention proposes a three-dimensional ground magnetic tensor fast calculation method, device, equipment and medium.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows: On the one hand, the present invention provides a three-dimensional ground magnetic tensor fast calculation method, including the following steps: Determine the target area of magnetic geological exploration and the size, shape and susceptibility distribution of abnormal bodies in the target area, and set the observation height; Construct a target area model including an abnormal body model, and perform three-dimensional grid division on the target area model including the abnormal body model; For the abnormal body model in the target area model after three-dimensional grid division, the magnetic susceptibility distribution range of each layer of the abnormal body model is set, and the magnetic intensity of each layer of the abnormal body model is calculated; The kernel function coefficient matrix of each layer of abnormal body model is calculated by using compression storage strategy; The three-dimensional ground magnetic tensor at the observation height is obtained by performing two-dimensional convolution of the kernel function coefficient matrix of each layer of the anomaly model calculated by two-dimensional fast Fourier transform and the magnetization intensity.

[0007] Optionally, the target area model including the abnormal body model is divided into three-dimensional grids, and the target area model and the abnormal body model in the target area model are divided into a plurality of right prism units; wherein the target area is along x , y , z The number of right prism units divided in the direction is , , , the abnormal body model follows x , y , z The number of right prism units divided in the direction is , , .

[0008] Optionally, setting a magnetic susceptibility distribution range of each layer of abnormal body model and calculating the magnetic intensity of each layer of abnormal body model include: According to the Earth's main magnetic field model, the Earth's main magnetic field of each upright prism unit in each layer of the anomaly model is calculated, and then the Earth's main magnetic field of each layer of the anomaly model is obtained; Based on the Earth's main magnetic field and the magnetic susceptibility distribution range of each layer of anomaly model, the magnetic intensity of each layer of anomaly model is calculated. .

[0009] Optionally, according to the Earth's main magnetic field model, the Earth's main magnetic field of each right prism unit in the anomaly model is calculated as follows: ; in, Indicates the abnormal body model numbered The coordinates of the right prism unit, ; ; ; Indicates the abnormal body model numbered The Earth's main magnetic field of a right prism unit, represents the local magnetic inclination, represents the local magnetic declination, , , respectively represent the three components of the Earth's main magnetic field in the x , y , z directions.

[0010] Set the observation height for the target area , and the number of observation points at the observation height is . Use the compressed storage strategy to calculate the kernel function coefficient matrix of the anomaly body model for the th layer, including: Calculate the kernel function coefficient corresponding to the vertical prism unit numbered in the anomaly body model of the th layer through the following formula: ; where , , respectively represent the th layer anomaly body model, the kernel function coefficient components in the direction of the vertical prism unit numbered x , y , z ; , , , where ; ; ; ; ; , , respectively represent the intervals between the centers of the vertical prism units dissected along the x , y , z directions, , represents the vacuum permeability; Based on the kernel function coefficients corresponding to each vertical prism unit in the anomaly body model of the th layer, obtain the kernel function coefficient matrix of the anomaly body model of the th layer .

[0011] Perform a two-dimensional convolution of the kernel function coefficient matrix of each layer's anomaly body model calculated by the two-dimensional fast Fourier transform and the magnetization intensity to obtain the three-dimensional ground magnetic tensor at the observation height : ; ; In the formula, and represents the Fourier transform pair, Representing the magnetic tensor in the wavenumber domain , Indicates the front of the extracted matrix OK List.

[0012] On the other hand, a three-dimensional ground magnetic tensor fast calculation device is provided, comprising: The first module is used to determine the target area for magnetic geological exploration and the size, shape and magnetic susceptibility distribution of the anomaly in the target area, and set the observation height; The second module is used to construct a target area model including the abnormal body model, and perform three-dimensional grid division on the target area model including the abnormal body model; The third module is used to set the magnetic susceptibility distribution range of each layer of the abnormal body model in the target area model after three-dimensional grid division, and calculate the magnetization intensity of each layer of the abnormal body model; The fourth module is used to calculate the kernel function coefficient matrix of each layer of abnormal body model by using a compression storage strategy; The fifth module is used to perform two-dimensional convolution of the kernel function coefficient matrix of each layer of the anomaly body model calculated by two-dimensional fast Fourier transform and the magnetization intensity to obtain the three-dimensional ground magnetic tensor at the observation height.

[0013] Optionally, in the second module, the target area model and the abnormal body model in the target area model are divided into a plurality of right prism units. x , y , z The number of right prism units divided in the direction is , , , the abnormal body model follows x , y , z The number of right prism units divided in the direction is , , ; In the fourth module, set the observation height of the target area , observation height The number of observation points is , using the compression storage strategy to calculate the The kernel function coefficient matrix of the layer anomaly model includes: Calculate the The number of the layer anomaly model is The corresponding kernel function coefficient of the right prism unit is: ; Among them, , , respectively represent the th layer abnormal body model, the kernel function coefficient components in the -th upright prism unit in the x , y , z directions; , , , , , , , , , , respectively represent the intervals between the centers of the upright prism units dissected along the x , y , z directions, , represents the vacuum permeability; Based on the kernel function coefficients corresponding to each upright prism unit in the th layer abnormal body model, the kernel function coefficient matrix of the th layer abnormal body model is obtained.

[0014] On the other hand, the present invention provides a computer device, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the steps of the above-mentioned three-dimensional ground magnetic tensor fast calculation method are implemented.

[0015] On the other hand, the present invention provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by the processor, the steps of the above-mentioned three-dimensional ground magnetic tensor fast calculation method are implemented.

[0016] On the other hand, the present invention provides a computer program product. The computer program product is stored on a computer-readable storage medium and includes computer instructions. When the computer instructions are run by the processor, the computer device implements the steps of the above-mentioned three-dimensional ground magnetic tensor fast calculation method.

[0017] Compared with the prior art, the technical effects of the present invention are as follows: The present invention uses a compressed storage strategy to calculate the kernel function coefficient matrix of each layer abnormal body model. On the one hand, it can effectively ensure the calculation accuracy. On the other hand, it can further reduce the calculation and storage of the kernel function, and further reduce the discrete convolution time on the premise of ensuring the calculation accuracy, realizing the fast forward calculation of the three-dimensional ground magnetic tensor. Brief Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for describing the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0019] Figure 1 It is a flowchart of a fast calculation method for three-dimensional ground magnetic tensor proposed for an embodiment; Figure 2 It is a schematic diagram of a target area model containing an anomaly model in a simulation example, where Figure 2 (a) is an x-y plane cross-sectional view of the target area model containing the anomaly model, Figure 2 (b) is an x-z plane cross-sectional view of the target area model containing the anomaly model; Figure 3 It is a plane contour map of the Bxx component of the surface magnetic tensor calculated by using the fast calculation method for three-dimensional ground magnetic tensor provided by the present invention; Figure 4 It is a plane contour map of the Bxx component of the surface magnetic tensor calculated by using the analytical solution; Figure 5 It is a relative error result map of the Bxx component of the magnetic tensor calculated by using the analytical solution and the fast calculation method for three-dimensional ground magnetic tensor provided by the present invention. Detailed Description of the Embodiments

[0020] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0021] Refer to Figure 1 , Figure 1 It is a flowchart of a fast calculation method for three-dimensional ground magnetic tensor proposed for an embodiment, including: Determine the target area of magnetic method geological exploration and the size, shape and susceptibility distribution of the anomalies in the target area, and set the observation height; Construct a target area model containing the anomaly model, and perform three-dimensional grid division on the target area model containing the anomaly model; For the abnormal body model in the target area model after three-dimensional grid division, the magnetic susceptibility distribution range of each layer of the abnormal body model is set, and the magnetic intensity of each layer of the abnormal body model is calculated; The kernel function coefficient matrix of each layer of abnormal body model is calculated using a compression storage strategy; The three-dimensional ground magnetic tensor at the observation height is obtained by performing two-dimensional convolution of the kernel function coefficient matrix of each layer of the anomaly model calculated by two-dimensional fast Fourier transform and the magnetization intensity.

[0022] At this point, fast and high-precision forward simulation of three-dimensional magnetic gradient tensor has been achieved.

[0023] The calculation formula of three-dimensional ground magnetic tensor can be expressed as:

[0024] In the formula, B represents the calculated magnetic tensor at a certain observation height, G represents the kernel function coefficient matrix, and M represents the magnetization intensity. Therefore, to obtain the three-dimensional ground magnetic tensor at the observation height, it is necessary to first calculate the magnetization intensity and the kernel function coefficient matrix.

[0025] Magnetic Tensor B There are 6 components, namely Bxx , Byy , Bzz , Bxy , Bxz and Byz , such as the horizontal component of the magnetic tensor Bxx The expression can be further expressed as: ; The anomaly described in this embodiment can be a complex geological body with any geometric shape and any magnetic susceptibility distribution. The target area model including the anomaly model is divided into three-dimensional grids, and the target area model and the anomaly model in the target area model are divided into multiple right prism units; wherein the target area is along x , y , z The number of right prism units divided in the direction is , , , the abnormal body model follows x , y , z The number of right prism units divided in the direction is , , .

[0026] The magnetic susceptibility distribution range of each layer of abnormal body model is set, and the magnetic intensity of each layer of abnormal body model is calculated, including: According to the Earth's main magnetic field model, calculate the Earth's main magnetic field of each upright prism unit in the anomaly body model of each layer, and then obtain the Earth's main magnetic field of the anomaly body model of each layer.

[0027] Specifically, the Earth's main magnetic field of each upright prism unit in the anomaly body model of the n -th layer includes x , y , z components in the three directions, and there are: ; Among them, represents the coordinates of the upright prism unit numbered in the anomaly body model, ; ; ; represents the Earth's main magnetic field of the upright prism unit numbered in the anomaly body model, represents the local magnetic dip angle, represents the local magnetic declination, , , respectively represent the three components of the Earth's main magnetic field in the x , y , z directions.

[0028] Based on the Earth's main magnetic field of the anomaly body model of each layer and the distribution range of the magnetic susceptibility of the anomaly body model of each layer, calculate the magnetization intensity of the anomaly body model of each layer.

[0029] Specifically, the magnetization intensity of each upright prism unit in the anomaly body model of the n -th layer includes x , y , z components in the three directions, and there are: ; Among them represents the magnetic susceptibility of the upright prism unit numbered ( l , m , n ) in the anomaly body model.

[0030] Set the observation height for the target area. The magnetic tensor B has 6 components, which are respectively Bxx , Byy , Bzz , Bxy , Bxz andByz , the observation height , the number of observation points on , using a compressed storage strategy to calculate the kernel function coefficient matrix of the anomaly body model in the th layer, including: Calculate the corresponding kernel function coefficient of the vertical prism unit numbered in the anomaly body model of the th layer through the following formula: ; Among them, , , respectively represent the th layer anomaly body model, the th numbered vertical prism unit's x , y , z direction kernel function coefficient components; , , , where, ; ; ; ; ; , , respectively represent the intervals between the centers of the vertical prism units divided along the x , y , z directions, , represents the vacuum permeability. In this embodiment, the midpoint integration formula can be used to calculate the kernel function coefficient matrix, effectively improving the calculation efficiency of the kernel function coefficient matrix.

[0031] Based on the kernel function coefficients corresponding to each vertical prism unit in the anomaly body model of the th layer, the kernel function coefficient matrix of the anomaly body model of the th layer is obtained .

[0032] The th layer anomaly body model's kernel function coefficient matrix has a maximum size of the coefficient matrix to be stored and calculated as , and for each layer of anomaly body model They can be the same or different, which is determined by the magnetic susceptibility distribution of each layer of the anomaly model and the size of the observation grid. This means that the size of the kernel function coefficient matrix for each layer can be the same or different, and they are all related to the anomaly model grid. When the number of upright prism body units in the dissection of a certain layer of the anomaly model is small, it means that the computational amount and storage amount of the kernel function coefficient matrix to be calculated will be greatly reduced. Therefore, the compressed storage strategy of the kernel matrix is adopted to further improve the efficiency of the forward calculation and reduce the memory consumption at the same time.

[0033] Finally, the two-dimensional convolution of the kernel function coefficient matrix of each layer of the anomaly model and the magnetization intensity calculated by the two-dimensional fast Fourier transform is used to obtain the three-dimensional ground magnetic tensor at the observation height. : ; ; In the formula, and represent the Fourier transform pair, represents the magnetic tensor in the wavenumber domain , represents extracting the first rows columns of the matrix.

[0034] In an embodiment, a three-dimensional ground magnetic tensor fast calculation device is provided, including: The first module is used to determine the target area of the magnetic method geological exploration and the size, shape and magnetic susceptibility distribution of the anomalies in the target area, and set the observation height; The second module is used to construct a target area model including the anomaly model and perform three-dimensional grid division on the target area model including the anomaly model; The third module is used to set the magnetic susceptibility distribution range of each layer of the anomaly model in the anomaly model of the target area model after three-dimensional grid division and calculate the magnetization intensity of each layer of the anomaly model; The fourth module is used to calculate the kernel function coefficient matrix of each layer of the anomaly model by adopting the compressed storage strategy; The fifth module is used to perform two-dimensional convolution of the kernel function coefficient matrix of each layer of the anomaly model and the magnetization intensity calculated by the two-dimensional fast Fourier transform to obtain the three-dimensional ground magnetic tensor at the observation height.

[0035] Next, the method of this embodiment is verified through specific simulation examples.

[0036] In this example: Referring to Figure 2 , it is a schematic diagram of the target area model including the anomaly model in this example, where Figure 2 (a) is the x-y plane cross-sectional view of the target area model including the anomaly model,Figure 2 Figure (b) is the x-z plane cross-sectional view of the target area model containing the anomalous body model. There is a prismatic anomalous body within the target area. The range of the target area is: in both the x and y directions, from -500 m to 500 m, and in the z direction, from 0 m to 1000 m (the positive direction of the z-axis is vertically downward). The three-dimensional grid division interval is 10 m, and the entire target area is divided into 100×100×100 cells. The distribution range of the prismatic anomalous body is: in both the x and y directions, from -200 m to 200 m, and in the z direction, from 400 m to 600 m. The intensity of the Earth's normal field is 50000 nT, the magnetic inclination and magnetic declination are 45° and 5° respectively, the magnetic susceptibility of the prismatic anomalous body is 0.01 SI, and the magnetic susceptibility of the background medium is 0 SI.

[0037] The method of this embodiment is implemented by programming in Fortran language. The configuration of the personal computer used to run the program is: CPU - Inter Core i5 - 10210U, with a main frequency of 2.10 GHz. Next, the anomalous values of the Bxx component of the surface magnetic tensor on the ground are calculated respectively based on the three-dimensional ground magnetic tensor fast calculation method provided in this embodiment and using the analytical solution.

[0038] Figure 3 Figure is the plane contour map of the Bxx component of the surface magnetic tensor calculated by using the three-dimensional ground magnetic tensor fast calculation method provided in this embodiment; Figure 4 Figure is the plane contour map of the Bxx component of the surface magnetic tensor calculated by using the analytical solution; Figure 5 Figure is the relative error result map of the Bxx component of the magnetic tensor calculated by using the analytical solution and the three-dimensional ground magnetic tensor fast calculation method provided in this embodiment. From Figure 3 、 Figure 4 It can be seen from the two figures that the morphological agreement between the calculation results of the analytical solution and the three-dimensional ground magnetic tensor fast calculation method provided in this embodiment is very good. From Figure 5 it can be seen that the relative error of the entire plane is less than 4.94×10-2%, indicating that the calculation accuracy of the method of this embodiment is very high.

[0039] In summary, in this embodiment, the size of the target area, the size of the anomaly body, and the observation height are first determined. The three-dimensional models corresponding to the target area and the anomaly body are uniformly discretized by three-dimensional meshing. According to the magnetic susceptibility distribution of the anomaly body model in different layers, the midpoint integration is used to quickly calculate the kernel function coefficient matrix. Then, according to the Toeplitz property of the matrix during grid uniform discretization, a compressed storage method is used to reduce the calculation and storage of the kernel matrix elements. Finally, the two-dimensional fast Fourier transform is used to realize the fast convolution calculation of the kernel matrix and the magnetic susceptibility, thereby realizing the fast forward calculation of the three-dimensional magnetic tensor. Compared with the traditional analytical method or numerical integration method, this embodiment greatly improves the efficiency of the forward calculation of the three-dimensional magnetic tensor while ensuring the calculation accuracy. Specifically, the midpoint integration can greatly improve the calculation efficiency of the kernel matrix elements. Further, the compressed storage method of the kernel matrix is used to further reduce the calculation amount, memory requirement, and discrete convolution time of the kernel matrix, thereby greatly reducing the calculation cost, memory requirement, and convolution calculation amount of the kernel function coefficient matrix.

[0040] On the other hand, this embodiment provides a computer device, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the steps of the three-dimensional ground magnetic tensor fast calculation method provided in any of the above embodiments are implemented. This computer device may be a server. The computer device includes a processor, a memory, a network interface, and a database connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store sample data. The network interface of the computer device is used to communicate with an external terminal through a network connection.

[0041] On the other hand, this embodiment provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the three-dimensional ground magnetic tensor fast calculation method provided in any of the above embodiments are implemented.

[0042] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, storage, database, or other medium used in the embodiments provided in the present application can include non-volatile and / or volatile memories. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and Rambus dynamic RAM (RDRAM), etc.

[0043] Matters not described in this embodiment are well-known technologies.

[0044] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0045] The above-described embodiments merely represent several implementation manners of the present application. Their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

[0046] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A fast calculation method for three-dimensional ground magnetic tensor, characterized in that, Including the following steps: Determine the target area of magnetic method geological exploration, as well as the size, shape and magnetic susceptibility distribution of abnormal bodies within the target area, and set the observation height; Construct a target area model containing an abnormal body model, and perform three-dimensional grid division on the target area model containing the abnormal body model; The target area model including the abnormal body model is divided into three-dimensional grids, and the target area model and the abnormal body model in the target area model are divided into a plurality of right prism units; wherein the target area is along x , y , z The number of right prism units divided in the direction is , , , the abnormal body model follows x , y , z The number of right prism units divided in the direction is , , ; For the abnormal body model in the target area model after three-dimensional grid division, set the magnetic susceptibility distribution range of each layer of the abnormal body model, and calculate the magnetization intensity of each layer of the abnormal body model; According to the size of each upright prism unit in the abnormal body model in the target area model after three-dimensional grid division and the distance between each vertex and each observation point, adopt a compressed storage strategy, and use a weighted Gaussian kernel function to calculate the components of the kernel function coefficients describing the magnetic anomaly response laws of each layer of the abnormal body model in three orthogonal directions in three-dimensional space, and integrate them to form a kernel function coefficient matrix; Use two-dimensional fast Fourier transform to calculate the two-dimensional convolution of the kernel function coefficient matrix and the magnetization intensity of each layer of the abnormal body model to obtain the three-dimensional ground magnetic tensor at the observation height; 2. The rapid calculation method of three-dimensional ground magnetic tensor according to claim 1, characterized in that, Set the magnetic susceptibility distribution range of each layer of the abnormal body model, and calculate the magnetization intensity of each layer of the abnormal body model, including: According to the earth's main magnetic field model, calculate the earth's main magnetic field of each upright prism unit in each layer of the abnormal body model, and then obtain the earth's main magnetic field of each layer of the abnormal body model; Calculate the magnetization intensity of each layer of anomaly body model based on the Earth's main magnetic field of each layer of anomaly body model and the distribution range of magnetic susceptibility of each layer of anomaly body model .

3. The three-dimensional ground magnetic tensor fast calculation method according to claim 2, characterized in that According to the earth's main magnetic field model, calculate the earth's main magnetic field of each upright prism unit in the abnormal body model as follows: ； Among them, represents the coordinates of the upright prism unit numbered in the abnormal body model; ; ; ; represents the main geomagnetic field of the upright prism unit numbered in the abnormal body model, represents the local magnetic dip angle, represents the local magnetic declination, , , respectively represent the three components of the main geomagnetic field in the x , y , z directions.

4. The three-dimensional ground magnetic tensor fast calculation method according to claim 2 or 3, characterized in that Set the observation height for the target area , the observation height The number of observation points above is , adopt the compressed storage strategy to calculate the kernel function coefficient matrix of the anomaly body model of the layer, including: Calculate the corresponding kernel function coefficient of the upright prism unit numbered in the layer abnormal body model by the following formula: ； Among them, , , respectively represent the th layer abnormal body model, the -numbered upright prism unit's x , y , z direction kernel function coefficient components; , , , among which, ; ; ; ; ; , , respectively represent the intervals between the centers of the upright prism units dissected along the x , y , z directions, , represents the vacuum permeability; Based on the kernel function coefficients corresponding to each upright prism unit in the -layer anomaly body model, the kernel function coefficient matrix of the -layer anomaly body model is obtained .

5. The rapid calculation method of three-dimensional ground magnetic tensor according to claim 4, characterized in that The two-dimensional convolution of the kernel function coefficient matrix of each layer of the anomaly body model calculated by two-dimensional fast Fourier transform and the magnetization intensity is used to obtain the three-dimensional ground magnetic tensor at the observation height. : ； ； In the formula, and represent a Fourier transform pair, represents the magnetic tensor in the wavenumber domain , represents the first rows columns of the extraction matrix.

6. Three-dimensional ground magnetic tensor rapid calculation device, characterized in that Including: The first module is used to determine the target area of magnetic method geological exploration, as well as the size, shape and magnetic susceptibility distribution of abnormal bodies within the target area, and set the observation height; The second module is used to construct a target area model containing an abnormal body model, and perform three-dimensional grid division on the target area model containing the abnormal body model; The third module is used to, for the abnormal body model in the target area model after three-dimensional grid division, set the magnetic susceptibility distribution range of each layer of the abnormal body model, and calculate the magnetization intensity of each layer of the abnormal body model; The fourth module is used to calculate the kernel function coefficient matrix of each layer of the abnormal body model by adopting a compressed storage strategy; The fifth module is used to use two-dimensional fast Fourier transform to calculate the two-dimensional convolution of the kernel function coefficient matrix and the magnetization intensity of each layer of the abnormal body model to obtain the three-dimensional ground magnetic tensor at the observation height; 7. The three-dimensional ground magnetic tensor rapid calculation device according to claim 6, wherein In the second module, the target area model and the abnormal body model within the target area model are divided into multiple upright prism units. The target area is along x , y , z The number of upright prism units divided in the directions are , , respectively. For the abnormal body model, the number of upright prism units divided along x , y , z the directions are , , respectively. In the fourth module, the observation height of the target area is set. The number of observation points at the observation height is . The kernel function coefficient matrix of the abnormal body model in the layer is calculated using a compressed storage strategy, including: Calculate through the following formula for the kernel function coefficient corresponding to the vertical prism element numbered in the anomaly body model of the ； Among them, , , respectively represent the -th layer of the abnormal body model, and the -th upright prism unit's x , y , z -direction kernel function coefficient components; , , , , , , , , , , respectively represent the intervals between the centers of the upright prism units divided along the x, y, and z directions, , represents the vacuum permeability; Based on the kernel function coefficients corresponding to each upright prism unit in the -layer anomaly body model, the kernel function coefficient matrix of the -layer anomaly body model is obtained .

8. A computer device, comprising a memory and a processor, the memory storing a computer program, characterized in that, When the processor executes the computer program, it realizes the steps of the three-dimensional ground magnetic tensor fast calculation method as described in claim 1.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it realizes the steps of the three-dimensional ground magnetic tensor fast calculation method as described in claim 1.

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