Magnetotelluric simulation method and device based on non-fitting grid and storage medium

Abstract

The application discloses a magnetotelluric simulation method and device based on a non-fitting grid and a storage medium. The method comprises the following steps: obtaining initial non-fitting grid information; determining a physical field with singularity; determining a physical field without singularity based on the initial non-fitting grid information; obtaining magnetotelluric representation information; and performing numerical calculation on the magnetotelluric representation information based on the physical field with singularity and the physical field without singularity to obtain a corresponding simulation result. The calculation region of three-dimensional earth is determined by using the non-fitting grid, compared with the fitting grid method in the prior art, the geometric error in the calculation process can be effectively reduced, the calculation amount in the calculation process is reduced, and the calculation efficiency is improved. On the other hand, the magnetotelluric simulation process of the three-dimensional earth is optimized and decomposed by using field decomposition, so that the error of the numerical solution can reach high-order accuracy in theory, and the accuracy of the simulation result is effectively improved, and the actual simulation requirement is met.

Description

Technical Field

[0001] This invention relates to the field of geological simulation technology, specifically to a magnetotelluric simulation method based on a nonfitted grid, a magnetotelluric simulation device based on a nonfitted grid, and a computer-readable storage medium. Background Technology

[0002] Magnetotelluric exploration is a method of studying geological structures by using naturally changing electromagnetic fields or artificially established stable electromagnetic fields. For example, typical calculation methods include the DC resistivity method, which mainly generates electromagnetic field data by measuring artificially established stable current fields. Based on numerical calculation methods, the distribution patterns of rocks or minerals with different electrical conductivity in the Earth's crust are obtained, thereby solving mineral exploration and other geological problems.

[0003] In application, the forward modeling of the DC resistivity method requires solving a three-dimensional resistivity problem. Existing techniques for this problem include the finite difference method, the finite element method, and the boundary integral method. All of these methods use body-fitted meshes for calculation. Body-fitted meshes are implemented by replacing the curved edges of complex structures with the straight edges of the mesh elements. Technicians have found that these methods have at least the following technical problems during application:

[0004] On the one hand, geometric errors are introduced during mesh discretization, and when the geometric errors are too large, they directly affect the final calculation accuracy. On the other hand, it is extremely difficult to generate high-quality body-fit meshes for complex structures, often consuming a lot of engineers' time. Thirdly, the above methods only have first-order accuracy, and for three-dimensional problems, obtaining more accurate calculation results will bring a huge amount of computation, greatly increasing the computational difficulty. Summary of the Invention

[0005] To overcome the aforementioned technical problems in the prior art, this invention provides a magnetotelluric simulation method based on a nonfitted grid. By employing a nonfitted grid method to analyze and simulate three-dimensional magnetotelluric data, and by using field decomposition to optimize the simulation process, the accuracy and efficiency of the simulation calculation are improved.

[0006] To achieve the above objectives, embodiments of the present invention provide a magnetotelluric simulation method based on an unfitted grid. The method includes: acquiring initial unfitted grid information; determining a singular physical field; calculating and determining a desingular physical field based on the initial unfitted grid information; acquiring the characterization information of the magnetotelluric field; performing numerical calculations on the characterization information of the magnetotelluric field based on the singular physical field and the desingular physical field to obtain corresponding simulation results.

[0007] Preferably, obtaining the initial nonfit mesh information includes: obtaining geological structure description information of the region to be simulated; determining the region to be calculated based on the geological structure description information; and determining the initial nonfit mesh information based on the region to be calculated.

[0008] Preferably, the step of calculating and determining the singularity-reducing physical field based on the initial nonfit mesh information includes: determining the weak definition information that the initial nonfit mesh information satisfies for the singularity-reducing physical field; obtaining a preset finite element function space, and determining the corresponding finite element basis functions based on the finite element function space; calculating and determining a discrete system based on the weak definition information and the finite element basis functions; and calculating and determining the singularity-reducing physical field based on the discrete system.

[0009] Preferably, determining the weak definition information satisfied by the initial unfitted mesh information for the singularity-reducing physical field includes: obtaining the initial weak definition information of the initial unfitted mesh information for the singularity-reducing physical field; obtaining optimization conditions; optimizing the initial weak definition information based on the optimization conditions to obtain optimized weak definition information of the singularity-reducing physical field.

[0010] Preferably, the step of calculating and determining the discrete system based on the weakly defined information and the finite element basis functions includes: calculating a first discrete coefficient term and a second discrete coefficient term based on the weakly defined information and the finite element basis functions respectively; obtaining a preset coefficient calculation rule; and processing the first discrete coefficient term and the second discrete coefficient term based on the preset coefficient calculation rule to obtain the corresponding discrete system.

[0011] Preferably, the step of performing numerical calculations on the magnetotelluric characterization information based on the singular physical field and the desingular physical field to obtain corresponding simulation results includes: calculating and determining potential characterization information based on the singular physical field and the desingular physical field; obtaining a preset resistivity characterization rule; calculating and obtaining resistivity characterization information based on the preset resistivity characterization rule; and generating corresponding simulation results based on the potential characterization information and the resistivity characterization information.

[0012] Accordingly, embodiments of the present invention also provide a magnetotelluric simulation device based on an unfitted grid. The device includes: an initial information acquisition unit for acquiring initial unfitted grid information; a first field determination unit for determining a singular physical field; a second field determination unit for calculating and determining a desingular physical field based on the initial unfitted grid information; a characterization information acquisition unit for acquiring characterization information of the magnetotelluric field; and a simulation unit for performing numerical calculations on the characterization information of the magnetotelluric field based on the singular physical field and the desingular physical field to obtain corresponding simulation results.

[0013] Preferably, the initial information acquisition unit includes: a geological information acquisition module for acquiring geological structure description information of the area to be simulated; a calculation area determination module for determining the area to be calculated based on the geological structure description information; and an initial information determination module for determining initial nonfit grid information based on the area to be calculated.

[0014] Preferably, the second field determination unit includes: a weak definition information determination module, used to determine the weak definition information satisfied by the initial nonfit mesh information for the singularity-removing physical field; a finite element function determination module, used to obtain a preset finite element function space and determine the corresponding finite element basis functions based on the finite element function space; a discrete coefficient determination module, used to calculate and determine the discrete system based on the weak definition information and the finite element basis functions; and a singularity-removing physical field determination module, used to calculate and determine the singularity-removing physical field based on the discrete system.

[0015] Preferably, the weak definition information determination module is specifically used for: obtaining the initial weak definition information satisfied by the initial nonfit mesh information for the singularity-reducing physical field; obtaining optimization conditions; optimizing the initial weak definition information based on the optimization conditions to obtain optimized singularity-reducing physical field weak definition information.

[0016] Preferably, the discrete coefficient determination module is specifically used to: calculate the first discrete coefficient term and the second discrete coefficient term based on the weakly defined information and the finite element basis functions respectively; obtain a preset coefficient calculation rule; and process the first discrete coefficient term and the second discrete coefficient term based on the preset coefficient calculation rule to obtain the corresponding discrete system.

[0017] Preferably, the simulation unit includes: a first calculation module for calculating and determining potential characterization information based on the singular physical field and the desingular physical field; a rule acquisition module for acquiring preset resistivity characterization rules; a second calculation module for calculating and obtaining resistivity characterization information based on the preset resistivity characterization information rules; and a simulation module for generating corresponding simulation results based on the potential characterization information and the resistivity characterization information.

[0018] On the other hand, embodiments of the present invention also provide a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method provided in the embodiments of the present invention.

[0019] The present invention has at least the following technical effects through the technical solution provided by the present invention:

[0020] By using an unfitted mesh to determine the computational region of the three-dimensional landmass to be simulated, compared with the fitted mesh method in the existing technology, geometric errors in the calculation process can be effectively reduced, and the amount of calculation can be reduced, thereby improving the computational efficiency.

[0021] On the other hand, by using field decomposition to optimize the geomagnetic simulation process of the three-dimensional earth, the error of the numerical solution can reach the theoretical high-order accuracy, thereby effectively improving the accuracy of the simulation results and meeting the actual simulation requirements.

[0022] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0023] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0024] Figure 1 This is a schematic diagram illustrating the application of the DC resistivity method provided in this embodiment of the invention;

[0025] Figure 2 This is a three-dimensional schematic diagram of the area to be measured provided in an embodiment of the present invention;

[0026] Figure 3 This is a flowchart illustrating the specific implementation of the magnetotelluric simulation method based on an unfitted grid provided in this embodiment of the invention.

[0027] Figure 4 This is a flowchart illustrating the specific implementation of obtaining initial unfitted grid information in the magnetotelluric simulation method based on unfitted grids provided in this embodiment of the invention.

[0028] Figure 5 This is a flowchart illustrating the specific implementation of determining singular physical fields in the magnetotelluric simulation method based on unfitted grids provided in this embodiment of the invention.

[0029] Figure 6 This is a schematic diagram of the terrain data to be simulated in the magnetotelluric simulation method based on an unfitted grid provided in an embodiment of the present invention.

[0030] Figure 7 This is a schematic diagram of the voltage distribution on the Earth's surface in the magnetotelluric simulation method based on an unfitted grid provided in this embodiment of the invention;

[0031] Figure 8 This is a schematic diagram of resistivity distribution on the Earth's surface in the magnetotelluric simulation method based on an unfitted grid provided in this embodiment of the invention;

[0032] Figure 9 This is a schematic diagram of the structure of the magnetotelluric simulation device based on an unfitted grid provided in an embodiment of the present invention. Detailed Implementation

[0033] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0034] In this invention, the terms "system" and "network" are used interchangeably. "Multiple" refers to two or more; therefore, in this invention, "multiple" can also be understood as "at least two." "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. Additionally, the character " / ", unless otherwise specified, generally indicates that the preceding and following related objects have an "or" relationship. Furthermore, it should be understood that in the description of this invention, terms such as "first" and "second" are used only for descriptive purposes and should not be construed as indicating or implying relative importance or order.

[0035] First, let's introduce the background technology of this invention.

[0036] As described above, existing three-dimensional magnetotelluric exploration methods mainly employ the DC resistivity method. Please refer to [link to relevant documentation]. Figure 1 This is a schematic diagram of the DC resistivity method in practical applications. Technicians establish a stable current field in the area to be measured to generate electromagnetic field data. Then, through numerical calculation, they obtain the distribution pattern of rocks or ores with different electrical conductivity in the Earth's crust, thereby solving mineral exploration and other geological problems. Therefore, high-precision electromagnetic forward and inverse calculations are extremely important.

[0037] In the current process of calculating three-dimensional resistivity, the mathematical model is characterized as follows:

[0038]

[0039] Where Ω represents the computational domain, Γ represents the interface representing the underground topography, and Γ s Γ represents the Earth's surface plane. ∞ Let σ(x) represent the infinite boundary of the underground surface, σ(x) represent the conductivity, I0 represent the magnitude of the current, and A represent the location of the point source [x]. A ,y A ,z A ], δ(A) represents the Dirac function in A. This represents the vector from point A to the boundary at infinity. Let r be the outward normal vector on the boundary at infinity, r be the distance from point A to the boundary at infinity, and u be the electric potential. [] represents jumps on the interface, and {} represents the mean value on the interface. The corresponding expressions are as follows:

[0040]

[0041] in and The outward normal vector on the surface has the following properties: Please see Figure 2 Γ is a three-dimensional schematic diagram of the region to be measured provided in an embodiment of the present invention. s The upper plane is represented by Γ, and the other five planes are represented by Γ. ∞ To address the aforementioned resistivity calculation problem, the main methods currently employed are the finite difference method, the finite element method, and the boundary integral method. However, these methods are all based on body-fitted meshes, which results in geometric errors, low accuracy (only first-order accuracy), and a large computational load, thus causing significant challenges for technical personnel.

[0042] Please see Figure 3 This invention provides a magnetotelluric simulation method based on an unfitted grid, the method comprising:

[0043] S10) Obtain initial unfitted grid information;

[0044] S20) Determine the physical field with singularity;

[0045] S30) Calculate and determine the singularity-removing physical field based on the initial nonfitted mesh information;

[0046] S40) Calculate and determine the characterization information of the magnetotelluric field based on the singular physical field and the de-singular physical field;

[0047] S50) Perform numerical calculations on the characterization information of the magnetotelluric data to obtain the corresponding simulation results.

[0048] In one possible implementation, the initial unfitted computational grid and other data required for the computation are first initialized; for details, please refer to [link to relevant documentation]. Figure 4 In this embodiment of the invention, obtaining the initial nonfitted mesh information includes:

[0049] S11) Obtain geological structure description information of the area to be simulated;

[0050] S12) Determine the region to be calculated based on the geological structure description information;

[0051] S13) Determine the initial unfitted mesh information based on the region to be calculated.

[0052] First, obtain the geological structure description information of the area to be simulated. For example, based on the exploration of the area to be simulated, obtain the horizontal set function representation of the interface and the size of the area to be calculated. Then, based on the size of the area to be calculated, mature software such as Gmsh and Tetgen can be used to generate an initial tetrahedral mesh file that can cover the calculation area. This mesh does not need to fit a complex interface.

[0053] In this embodiment of the invention, the three-dimensional space of the simulation region is determined by using an unfitted mesh method. Since it is not necessary to generate a fitted mesh, but rather the mesh is required to cover the computation region, the difficulty of generating a body-fitted mesh can be effectively reduced compared with existing methods. At the same time, it can achieve high-precision simulation results, thereby improving simulation efficiency and accuracy.

[0054] After determining the initial nonfitted mesh information, further processing is performed. In this embodiment of the invention, although the nonfitted mesh method can achieve the above-mentioned technical effects, in practical applications, for magnetotelluric problems, the right-hand side (current term) is a delta function, that is, a function with some singularity. According to existing common knowledge, the error accuracy of this singular function with respect to the mesh cell size is only 0.5, so it still does not meet the actual simulation requirements.

[0055] To address the aforementioned technical problems, a field decomposition method is employed to improve accuracy. For example, the problem concerning resistivity is characterized as u. h =G+u s Where G is a physical field with singularity, specifically... u s It is the physical field corresponding to the singularity removal. Based on this characterization, the singularity removal physical field u can be determined. s satisfy:

[0056]

[0057] After determining the singular physical field, we further determine the non-singular physical field.

[0058] Please see Figure 5 In this embodiment of the invention, the step of calculating and determining the singularity-free physical field based on the initial nonfit grid information includes:

[0059] S31) Determine the weak definition information that the initial unfitted mesh information satisfies for the singularity-reducing physical field;

[0060] S32) Obtain a preset finite element function space, and determine the corresponding finite element basis functions based on the finite element function space;

[0061] S33) Based on the weakly defined information and the finite element basis functions, the discrete system is calculated and determined;

[0062] S34) The singularity-free physical field is calculated and determined based on the discrete system.

[0063] In one possible implementation, the weak definition information of the initial nonfitted network information for the singularity-reducing physical field is first determined. In this embodiment of the invention, determining the weak definition information satisfied by the initial nonfitted network information for the singularity-reducing physical field includes: obtaining the initial weak definition information of the initial nonfitted network information for the singularity-reducing physical field; obtaining optimization conditions; and optimizing the initial weak definition information based on the optimization conditions to obtain optimized weak definition information of the singularity-reducing physical field.

[0064] For example, based on existing common knowledge, it is possible to obtain the following for singular physical fields u. s The initial weak definition information, for example, the initial weak definition information is the weak form definition of an unfitted mesh discontinuous finite element: Satisfy a h (u s ,v)=F h (v), specific, weak form a h (u s ,v) is characterized as:

[0065]

[0066] and weak form F h (v) is characterized as:

[0067]

[0068] Where β represents the symmetry term, which is generally taken as -1. λ, γ0, γ1 represent penalty factors, which are input parameters. h represents the boundary conditions, and g represents the interface conditions. The subscripts D, N, and R represent Dirichlet, Neumann, and Robin boundary conditions, respectively. h The interface of a UI unit, ε h This represents the face of all units (including interface units and non-interface units). The diameter of the mesh cell is represented by K, the volume is represented by K, and the surface is represented by e.

[0069] Since the above characterization information is based on general conditions, and further optimization can be performed for the resistivity characterization problem, optimization conditions are obtained at this point. For example, these optimization conditions can be determined as: g D =0,h D =0,,Σ N =Γ s ,Σ R =Γ ∞ , f = 0, Therefore, based on this optimization condition, the weak form F... h (v) Optimization yields:

[0070] That is, according to the above a h (u s ,v) and the optimized F h (v) can obtain optimized weak definition information.

[0071] At this point, a preset finite element function space can be obtained. For example, the preset finite element function space V can be determined in advance according to relevant definitions. h And based on the finite element function space V h Determine the corresponding finite element basis functions, for example, the finite element basis functions are P-order finite element basis functions φ. i (i = 1, ..., N), where N is the number of finite element basis functions.

[0072] Then, based on the aforementioned weakly defined information and finite element basis functions, the discrete coefficients are calculated and determined. For example, in this embodiment of the invention, the discrete coefficient problem is a problem of solving the coefficient matrix A and the right-hand side term b. The step of calculating and determining the discrete system based on the weakly defined information and the finite element basis functions includes: calculating the first discrete coefficient term and the second discrete coefficient term based on the weakly defined information and the finite element basis functions respectively; obtaining a preset coefficient calculation rule; and processing the first discrete coefficient term and the second discrete coefficient term based on the preset coefficient calculation rule to obtain the corresponding discrete system.

[0073] Specifically, on the one hand, the first discrete coefficient term can be calculated based on the weakly defined information and the finite element basis functions. For example, this first discrete coefficient term is the coefficient matrix element A on the non-interface element. ij and the right-hand term b i Specifically, it can be characterized as:

[0074]

[0075]

[0076]

[0077] On the other hand, the second discrete coefficient term can be calculated based on weakly defined information and finite element basis functions. For example, this second discrete coefficient term is the coefficient matrix element A on the interface element (the element intersecting the interface). ij and the right-hand term b i Specifically, it can be characterized as:

[0078]

[0079]

[0080] At this point, a preset coefficient calculation rule is obtained. This preset coefficient calculation rule may include, but is not limited to, the sparse direct method or the preconditioned generalized minimum residual method (GMRES). The preconditions use the additive Schwarz method, and the preconditions for solving the subproblems employ the incomplete LU decomposition (ILU) method. Based on this preset coefficient calculation rule, the first and second discrete coefficient terms can be processed to obtain the corresponding discrete system. Specifically, it can be characterized as follows:

[0081] Ax = b

[0082] in, It is an unknown solution vector.

[0083] After determining the discrete system described above, the singularity-removing physical field u can be calculated based on the discrete system. s For example, the singular physical field u s Characterized as Based on the above-mentioned singular and desingular physical fields, the characterization information of magnetotellurics can be calculated and determined. For example, in the embodiments of the present invention, the characterization information includes electric potential and resistivity.

[0084] In this embodiment of the invention, the singularity of the source term is addressed by employing field decomposition, enabling the numerical solution error to reach theoretically high-order accuracy. Specifically, when a P-order polynomial is used as the basis function for discretization, the calculated numerical solution u... h and exact solution (or reference solution u) * L2 norm error It is of order P+1, which greatly improves the accuracy of numerical calculation and meets the actual simulation accuracy requirements.

[0085] In this embodiment of the invention, the step of performing numerical calculations on the magnetotelluric characterization information based on the singular physical field and the desingular physical field to obtain corresponding simulation results includes: calculating and determining potential characterization information based on the singular physical field and the desingular physical field; obtaining a preset resistivity characterization rule; calculating and obtaining resistivity characterization information based on the preset resistivity characterization rule; and generating corresponding simulation results based on the potential characterization information and the resistivity characterization information.

[0086] In one possible implementation, according to the above formula u h =G+u s Therefore, based on the calculations of the singular and non-singular physical fields, the corresponding electric potential u can be calculated and determined. hAt this point, a preset resistivity characterization rule is further obtained, for example, the preset resistivity characterization rule is: Therefore, given the calculated potential and resistivity characteristics, corresponding simulation results can be generated.

[0087] In this embodiment of the invention, by employing a magnetotelluric numerical simulation method based on a nonfitted grid, the accuracy of the simulation calculation can be effectively improved, while avoiding the problem of excessive computational load, thus improving computational efficiency and meeting the actual simulation calculation requirements.

[0088] In practical applications, the input parameters are first determined. These input parameters include, but are not limited to, the geological structure description information of the area to be simulated, the magnitude of the point source field current I0 = 1.0, the geological parameter σ(x), and the finite element calculation parameters. For example, if two areas need to be simulated, their geological parameters are σ1 = 0.5 and σ2 = 1.0, respectively. The finite element calculation parameters include, but are not limited to, the order of the basis functions and the penalty factor. In this embodiment of the invention, the order of the symmetry term is defaulted to 2, and the penalty factors λ, γ0, and γ1 are all 1.

[0089] At this point, the unfitted computational grid and other data for the region to be simulated are first determined. Pre-refinement operations may be necessary; for example, please refer to [link to relevant documentation]. Figure 6 This is a schematic diagram of the terrain data to be simulated according to an embodiment of the present invention. The area to be simulated is [-100, 100]. 3 The interface is a sinusoidal interface l(x,y,z)=-z+20sin(πy / 100.0), and the source point is located at x. A = [0,0,100], current magnitude I0 = 1.0.

[0090] Then, the source term singularity is handled using field separation, and the corresponding magnetotelluric characterization information is obtained. After performing numerical calculations on the above characterization information, the corresponding simulation results are obtained. For example, please refer to [link to relevant documentation]. Figure 7-8 The above are schematic diagrams of voltage distribution and resistivity distribution on the earth's surface, provided in embodiments of the present invention.

[0091] It should be noted that those skilled in the art will readily understand that when the smoothness of the solution calculated based on the above-mentioned discontinuous finite element function space is high, a continuous finite element function space can be used as a substitute to obtain a solution that better meets the actual needs. This should also fall within the protection scope of this invention, and will not be elaborated further here.

[0092] The magnetotelluric simulation device with a non-fitted grid provided in the embodiments of the present invention will be described below with reference to the accompanying drawings.

[0093] Please see Figure 9Based on the same inventive concept, embodiments of the present invention provide a magnetotelluric simulation device with an unfitted grid. The device includes: an initial information acquisition unit for acquiring initial unfitted grid information; a first field determination unit for determining a singular physical field; a second field determination unit for calculating and determining a desingular physical field based on the initial unfitted grid information; a characterization information acquisition unit for acquiring characterization information of the magnetotelluric field; and a simulation unit for performing numerical calculations on the characterization information of the magnetotelluric field based on the singular physical field and the desingular physical field to obtain corresponding simulation results.

[0094] In this embodiment of the invention, the initial information acquisition unit includes: a geological information acquisition module, used to acquire geological structure description information of the area to be simulated; a calculation area determination module, used to determine the area to be calculated based on the geological structure description information; and an initial information determination module, used to determine initial nonfit grid information based on the area to be calculated.

[0095] In this embodiment of the invention, the second field determination unit includes: a weak definition information determination module, used to determine the weak definition information satisfied by the initial nonfit mesh information for the singularity-removing physical field; a finite element function determination module, used to obtain a preset finite element function space and determine the corresponding finite element basis functions based on the finite element function space; a discrete coefficient determination module, used to calculate and determine the discrete system based on the weak definition information and the finite element basis functions; and a singularity-removing physical field determination module, used to calculate and determine the singularity-removing physical field based on the discrete system.

[0096] In this embodiment of the invention, the weak definition information determination module is specifically used to: obtain the initial weak definition information satisfied by the initial nonfit mesh information for the singularity-removing physical field; obtain optimization conditions; optimize the initial weak definition information based on the optimization conditions to obtain optimized singularity-removing physical field weak definition information.

[0097] In this embodiment of the invention, the discrete coefficient determination module is specifically used to: calculate the first discrete coefficient term and the second discrete coefficient term based on the weakly defined information and the finite element basis function, respectively; obtain a preset coefficient calculation rule; and process the first discrete coefficient term and the second discrete coefficient term based on the preset coefficient calculation rule to obtain the corresponding discrete system.

[0098] In this embodiment of the invention, the simulation unit includes: a first calculation module, used to calculate and determine potential characterization information based on the singular physical field and the desingular physical field; a rule acquisition module, used to acquire preset resistivity characterization rules; a second calculation module, used to calculate and obtain resistivity characterization information based on the preset resistivity characterization information rules; and a simulation module, used to generate corresponding simulation results based on the potential characterization information and the resistivity characterization information.

[0099] Furthermore, embodiments of the present invention also provide a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the methods described in the embodiments of the present invention.

[0100] The optional embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above embodiments. Within the scope of the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical solutions of the embodiments of the present invention, and these simple modifications all fall within the protection scope of the embodiments of the present invention.

[0101] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not describe the various possible combinations separately.

[0102] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program is stored in a storage medium and includes several instructions to cause a microcontroller, chip, or processor to execute all or part of the steps 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 a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0103] Furthermore, various different implementations of the present invention can be combined arbitrarily, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed in the present invention.

Claims

1. A method for magnetotelluric simulation based on a non-fitted grid, characterized in that, The method comprises: obtaining initial non-fitting grid information, comprising: obtaining geological structure description information of a region to be simulated; determining a region to be calculated based on the geological structure description information; determining initial non-fitting grid information based on the region to be calculated; determining a singular physical field; calculating a non-singular physical field based on the initial non-fitting grid information, comprising: determining weak definition information that the initial non-fitting grid information satisfies for the non-singular physical field; obtaining a preset finite element function space, determining corresponding finite element basis functions based on the finite element function space; calculating a discrete system based on the weak definition information and the finite element basis functions; calculating the non-singular physical field based on the discrete system; obtaining representation information of the magnetotelluric; performing numerical calculation on the representation information of the magnetotelluric based on the singular physical field and the non-singular physical field to obtain a corresponding simulation result.

2. The method of claim 1, wherein, The determination of the weak definition information that the initial non-fitting grid information satisfies for the non-singular physical field comprises: obtaining initial weak definition information that the initial non-fitting grid information satisfies for the non-singular physical field; obtaining an optimization condition; optimizing the initial weak definition information based on the optimization condition to obtain optimized non-singular physical field weak definition information.

3. The method of claim 1, wherein, The calculation of the discrete system based on the weak definition information and the finite element basis functions comprises: calculating a first discrete coefficient term and a second discrete coefficient term based on the weak definition information and the finite element basis functions, respectively; obtaining a preset coefficient calculation rule; processing the first discrete coefficient term and the second discrete coefficient term based on the preset coefficient calculation rule to obtain a corresponding discrete system.

4. The method of claim 1, wherein, The numerical calculation on the representation information of the magnetotelluric based on the singular physical field and the non-singular physical field to obtain a corresponding simulation result comprises: calculating potential representation information based on the singular physical field and the non-singular physical field; obtaining a preset resistivity representation information rule; calculating resistivity representation information based on the preset resistivity representation information rule; generating a corresponding simulation result based on the potential representation information and the resistivity representation information.

5. A non-fitted mesh-based magnetotelluric simulation apparatus, characterized by, The device comprises: an initial information obtaining unit configured to obtain initial non-fitting grid information; a first field determining unit configured to determine a singular physical field; a second field determining unit configured to calculate a non-singular physical field based on the initial non-fitting grid information; a representation information obtaining unit configured to obtain representation information of the magnetotelluric; a simulation unit configured to perform numerical calculation on the representation information of the magnetotelluric based on the singular physical field and the non-singular physical field to obtain a corresponding simulation result; The initial information obtaining unit comprises: a geological information obtaining module configured to obtain geological structure description information of a region to be simulated; a calculation region determining module configured to determine a region to be calculated based on the geological structure description information; an initial information determining module configured to determine initial non-fitting grid information based on the region to be calculated; The second field determining unit comprises: a weak definition information determination module, configured to determine weak definition information satisfied by the initial non-fitted grid information for the de-singularity physical field; a finite element function determination module, configured to obtain a preset finite element function space, and determine corresponding finite element base functions based on the finite element function space; a discrete coefficient determination module, configured to calculate and determine a discrete system based on the weak definition information and the finite element base functions; a de-singularity physical field determination module, configured to calculate and determine the de-singularity physical field based on the discrete system.

6. The apparatus of claim 5, wherein, The weak definition information determination module is specifically configured to: obtain initial weak definition information satisfied by the initial non-fitted grid information for the de-singularity physical field; obtain an optimization condition; optimize the initial weak definition information based on the optimization condition, to obtain optimized de-singularity physical field weak definition information.

7. The apparatus of claim 5, wherein, The discrete coefficient determination module is specifically configured to: calculate a first discrete coefficient item and a second discrete coefficient item based on the weak definition information and the finite element base functions, respectively; obtain a preset coefficient calculation rule; process the first discrete coefficient item and the second discrete coefficient item based on the preset coefficient calculation rule, to obtain a corresponding discrete system.

8. The apparatus of claim 5, wherein, The simulation unit includes: a first calculation module, configured to calculate and determine electric potential representation information based on the physical field with singularity and the de-singularity physical field; a rule obtaining module, configured to obtain a preset resistivity representation information rule; a second calculation module, configured to calculate and obtain resistivity representation information based on the preset resistivity representation information rule; a simulation module, configured to generate a corresponding simulation result based on the electric potential representation information and the resistivity representation information.

9. A computer readable storage medium having stored thereon a computer program, characterized in that, The program is executed by the processor to implement the method of any one of claims 1-4.

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