A method and apparatus for numerical simulation of a foreland thrust belt

Abstract

The application discloses a numerical simulation method and device for a foreland thrust belt, and the method comprises the following steps: determining and acquiring basic parameters required for numerical simulation; constructing a stratum model and setting the stratum model based on the basic parameters; setting boundary conditions for numerical simulation; solving a mass conservation equation, a momentum conservation equation and an energy conservation equation to obtain field data of a velocity field, a pressure field and a temperature field of the stratum model; solving a topographic diffusion equation and a river erosion rate equation to obtain evolution data of topography and geomorphology of the stratum model; solving a flexure isostatic equation to obtain a basement subsidence amplitude of the stratum model; and outputting the calculated data. The application can better simulate a geomorphology evolution process dominated by river erosion in an actual geological process.

Description

Technical Field

[0001] This invention relates to a numerical simulation method and apparatus for the deformation evolution of complex structures with multiple detachments in foreland thrust belts, belonging to the field of petroleum geological exploration technology. Background Technology

[0002] A foreland thrust / fold-thrust belt is located at the basin-mountain transition zone between an orogenic belt and a basin. It is a thrust system formed by the large-scale thrusting and tumbling of the orogenic belt towards the basin, and the subduction and collision of the basin block beneath the orogenic belt. Situated on the active limb of a foreland basin, this belt is a major location for abundant hydrocarbon accumulation. Exploration practice and research have also shown that foreland thrust belts possess rich hydrocarbon accumulations and play a crucial role in basin analysis and hydrocarbon exploration.

[0003] In the process of oil and gas exploration in foreland thrust zones or foreland basins, due to poor seismic data and strong structural ambiguity, numerical simulation technology has gradually become an important tool for studying the deformation mechanisms of complex structures in foreland thrust zones. However, because foreland thrust zones are subject to numerous controlling factors and have complex evolution processes, there are many key points and difficulties in the construction of their geological and numerical models. Numerical simulation studies on the evolution of foreland thrust zones are relatively few, especially those guiding oil and gas exploration with complex multi-slip structures. Summary of the Invention

[0004] The purpose of this invention is to address the problems of insufficient precision and reliability in existing numerical simulation techniques for the deformation evolution of complex structures with multiple detachments in foreland thrust belts, and to achieve numerical simulation of the deformation evolution of complex structures with multiple detachments in foreland thrust belts under the control of multiple factors.

[0005] This invention provides a numerical simulation method for foreland thrust belts, including:

[0006] Based on the requirements of numerical simulation and the geological data of the foreland thrust zone, which is the object of numerical simulation, the basic parameters required for numerical simulation are determined and obtained.

[0007] A formation model is constructed based on the formation distribution and well logging data of the numerical simulation object, and the formation model is set based on the basic parameters.

[0008] The boundary conditions for the numerical simulation are set based on the aforementioned basic parameters;

[0009] Based on the boundary conditions, the mass conservation equation, momentum conservation equation, and energy conservation equation are solved to obtain the velocity field, pressure field, and temperature field data of the stratigraphic model; the topographic diffusion equation and river erosion rate equation are solved to obtain the topographic evolution data of the stratigraphic model; and the flexural equilibrium equation is solved to obtain the basement settlement amplitude of the stratigraphic model.

[0010] Output the field data, the evolution data, and the basement subsidence magnitude.

[0011] Another aspect of the present invention provides a numerical simulation apparatus for foreland thrust belts, comprising:

[0012] The basic parameter acquisition module is used to determine and acquire the basic parameters required for numerical simulation based on the numerical simulation requirements and the geological data of the foreland thrust zone, which is the object of numerical simulation.

[0013] The formation model construction module is used to construct a formation model based on the formation distribution and well logging data of the numerical simulation object, and to set the formation model based on the basic parameters.

[0014] A boundary condition setting module is used to set the boundary conditions for numerical simulation based on the basic parameters.

[0015] The equation iterative solution module is used to solve the mass conservation equation, momentum conservation equation, and energy conservation equation based on the boundary conditions to obtain the field data of the velocity field, pressure field, and temperature field of the stratigraphic model; to solve the topographic diffusion equation and the river erosion rate equation to obtain the topographic evolution data of the stratigraphic model; and to solve the flexural equilibrium equation to obtain the basement settlement amplitude of the stratigraphic model.

[0016] The data output module is used to output the field data, the evolution data, and the basement settlement amplitude.

[0017] The present invention achieves at least the following technical effects in the above aspects:

[0018] (1) Compared with the previous numerical simulation technology for complex structures with multiple slips in the foreland thrust belt, the embodiments of the present invention adopt a surface process model that couples topographic diffusion and river erosion, which can better simulate the geomorphic evolution process dominated by river erosion in actual geological processes.

[0019] (2) Compared with the previous numerical simulation technology for complex structures with multiple slippage in the foreland thrust belt, the embodiments of the present invention adopt a basement settlement model of flexural settlement, which is closer to the geological facts.

[0020] (3) Compared with the previous numerical simulation technology for complex structures with multiple slippage in foreland thrust belts, the present invention realizes the simulation of deformation evolution of "double-sided convergence type" foreland thrust belts, and can complete the complex situation of simulating two foreland thrust belts at the same time.

[0021] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures described in the written description, claims, and drawings.

[0022] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0023] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0024] Figure 1 This is a flowchart of the numerical simulation method for the foreland thrust zone described in this invention.

[0025] Figure 2 This is a schematic diagram of the dual-sided convergence type boundary condition setting described in this invention.

[0026] Figure 3 This is a schematic diagram of the structure of the numerical simulation device for the foreland thrust zone described in this invention. Detailed Implementation

[0027] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0028] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with some aspects of the invention as detailed in the appended claims.

[0029] After research, the inventors discovered that the main platforms currently available for numerical simulation of foreland thrust zones include I2ELVIS, PFC2D, Sopale, MILAMIN_VEP, and VBOX. In the field of oil and gas exploration, FLAC is a commonly used platform for simulating complex multi-slip structures in foreland thrust zones. FLAC is a mechanical software platform developed by Itasca based on the continuous medium fast Lagrangian analysis method. It has a relatively complete interface, allowing for easy customization and optimization of models, and is therefore widely used in engineering geology research.

[0030] However, the numerical simulation techniques for complex foreland thrust belt structures with multiple detachments established based on the aforementioned platforms are mostly limited to the simulation of a single foreland thrust belt. By designing a "baffle-type" dynamic model and simultaneously coupling a relatively simple surface process model and a basement subsidence model, the simulation of foreland thrust belts can be achieved. This can simulate a single foreland thrust belt under the control of simple factors, but it cannot provide a more refined and reliable simulation of the deformation evolution of complex foreland thrust belt structures with multiple detachments under the control of multiple factors in actual geological backgrounds.

[0031] Existing simulation techniques for complex foreland thrust belt structures based on the FLAC platform have the following main drawbacks:

[0032] (1) The surface process model used is oversimplified. The surface erosion model used is usually a linear erosion model, that is, the erosion rate is proportional to the elevation:

[0033] E = aR

[0034] Where E represents the erosion rate, R represents the elevation, and a represents the erosion coefficient. While this model requires fewer parameters and has lower complexity, reducing the difficulty of data processing, it differs significantly from the actual erosion patterns in geological processes, which are primarily driven by river erosion. For sedimentary processes, a fill-in method has traditionally been used, assuming a sedimentary base level (e.g., 0 m) and filling in the elevation when it falls below this base level. This method not only fails to reflect actual sedimentary patterns but also leads to a material imbalance between erosion and sedimentation within the model. Since surface processes significantly influence the development of tectonic deformation in foreland thrust zones, using the simplified model described above introduces substantial uncertainty into the simulation results.

[0035] (2) The basement settlement model used is overly simplified. In orogenic belts and their surrounding areas, the lithosphere flexes due to the uplift of the terrain, the vertical load from foreland sedimentation, and the horizontal forces generated by plate convergence. Downward flexure is accompanied by the settlement process of the basement of the foreland thrust belt. The previous basement settlement method set a downward velocity at the bottom boundary of the model, which remained constant during the calculation, and the settlement rate was also based on experience without mathematical basis. In reality, the settlement rate is faster in areas with thick crust and slower in areas with thin crust. The magnitude of the settlement follows the principle of flexural equilibrium, and the settlement rate is not fixed. A settlement model with a fixed velocity will affect the dip angle of the detachment surface at the bottom of the foreland thrust belt, thus having a certain impact on the development of the structure.

[0036] (3) In previous numerical simulations of complex foreland thrust belt structures with multiple detachments, the initial model design was always "baffle-type". That is, it is assumed that one end of the initial horizontal rock layer is fixed, and the compression deformation process of the foreland thrust belt is achieved by horizontal compression of the other end. However, for some orogenic systems, such as the Tianshan Mountains, foreland thrust belts are developed on both the north and south sides of the mountain range. The thrust belts on both sides are in the same orogenic system and should not be simulated separately. In addition, for a single foreland thrust belt, there is no boundary similar to a "baffle", but rather a core of the orogenic belt that is constantly uplifting and changing in position. The "baffle-type" model is only a simplification, and this simplification will have a very large impact on the simulation results.

[0037] Therefore, this invention provides a numerical simulation method and apparatus for the deformation evolution of complex structures with multiple detachments in foreland thrust belts, in order to solve the above-mentioned problems. The invention will be described in detail below with specific embodiments.

[0038] A specific embodiment of the present invention is a numerical simulation method for the deformation evolution of complex structures with multiple detachments in foreland thrust belts, such as... Figure 1 As shown, the simulation method includes five steps: obtaining basic parameters; constructing a geological model; setting boundary conditions; iteratively solving the equations; and outputting data.

[0039] In the step of obtaining basic parameters, based on the requirements of numerical simulation and the geological data of the numerical simulation object, the basic parameters required for numerical simulation are determined and obtained, including stratigraphic model parameters, numerical simulation control parameters, thermal parameters, lithological physical property parameters, surface process parameters, and basement settlement parameters.

[0040] The stratigraphic model parameters include the width and depth of the stratigraphic model, the thickness of each rock layer, the lithology of the rocks, and the horizontal and vertical grid resolution. The numerical simulation control parameters include the convergence rate and iteration time step. The thermal parameters include thermal conductivity, specific heat capacity, coefficient of thermal expansion, geothermal gradient, heat production rate, and crustal heat flow. The physical properties of the rocks include the corresponding bulk modulus, shear modulus, density, cohesion, tensile strength, internal friction angle, expansion angle, and viscosity. Different rock lithologies may have different physical properties; for example, compared to general hard rocks such as limestone and dolomite, salt rocks have relatively low viscosity, while shale has relatively low cohesion and effective internal friction angle. The surface processes and basement subsidence parameters include average annual rainfall and effective elastic thickness. Average annual rainfall determines the surface erosion rate, while effective elastic thickness determines the magnitude of basement subsidence under the same lithospheric thickening conditions. These parameters are typically determined based on the problem to be studied in the numerical simulation, the geological overview of the study area, and other relevant geological data.

[0041] In the process of constructing the formation model, the formation model is constructed based on the formation distribution and well logging data of the numerical simulation object. Then, the lithology, thickness and morphology of each rock layer in the formation model are set based on the basic parameters, and the physical property parameters of the corresponding lithology are assigned. The initial temperature field is assembled into the formation model based on the geothermal gradient, and the initial geostress field is assembled into the formation model based on the static rock pressure.

[0042] The formation model is a highly abstract geometric model. Formation distribution and well logging data are obtained from literature and field observations, and then the formation model is derived through data abstraction. During the simulation, it can be delineated using code. The lithology, thickness, and morphology of the rocks are determined by the formation model and are considered its geometric parameters. The physical properties of the rock lithology include volume modulus, shear modulus, density, cohesion, tensile strength, internal friction angle, expansion angle, and viscosity. The geothermal gradient is one of the thermal parameters specified before the simulation and can be set based on literature.

[0043] In the step of setting boundary conditions, thermal boundary conditions and mechanical boundary conditions for numerical simulation are set.

[0044] The thermal boundary conditions take into account the actual situation of the geothermal field, setting the boundary conditions as a constant surface temperature, adiabatic left and right boundaries, and a constant heat flux value at the bottom boundary.

[0045] For mechanical boundary conditions, if simulating a typical single foreland thrust zone, a "baffle-type" boundary condition is used: one boundary is fixed horizontally, the other boundary is set to a constant horizontal velocity equal to the convergence rate, the bottom boundary is set to a constant vertical velocity (equal to the basement subsidence velocity) and a constant horizontal velocity (equal to the convergence rate), and the upper surface is a free surface. If simulating a double-converging model of a mountain range, i.e., simulating two foreland thrust zones simultaneously, a "double-converging type" boundary condition is used: the left boundary is set to a constant rightward horizontal velocity, the right boundary is set to a constant leftward horizontal velocity, both velocities being half the convergence rate, the bottom boundary is set to a constant vertical velocity (equal to the basement subsidence velocity) and constant horizontal velocities (equal to half the convergence rate) in opposite directions on both sides, and the upper surface is a free surface, as shown below. Figure 2 As shown, v x and v y These are the horizontal and vertical velocity boundary conditions for each model boundary, v c This represents the total convergence rate of the formation model.

[0046] In the iterative solution of equations, the numerical simulation method of this invention is to solve six major categories of equations: energy conservation equation, momentum conservation equation, mass conservation equation, topographic diffusion equation, river erosion-related equation, and flexure equation.

[0047] Numerical simulation first requires solving the three fundamental equations of conservation of mass, momentum, and energy to obtain data on the velocity, pressure, and temperature fields. These data can be presented in matrix form. The velocity field allows for mesh movement, resulting in large deformations and corresponding changes in the terrain, which is the primary purpose of numerical simulation. The pressure and temperature fields are helpful for analyzing the simulation results. Specifically, based on the initial geostress field, initial geothermal field, mechanical boundary conditions, thermal boundary conditions, and other physical properties, the following equations are solved:

[0048] mass conservation equation:

[0049]

[0050] Momentum conservation equation:

[0051]

[0052] Energy conservation equation:

[0053]

[0054] Among them, v x It is the velocity component in the horizontal direction of the stratigraphic model, v y Let σ′ be the velocity component in the vertical direction of the formation model. ijLet i and j be the deviatoric stress tensor, representing two different dimensions or directions, P be the dynamic pressure, ρ be the density, and q be the stress tensor. i For gravitational acceleration, C v Let q be the specific heat capacity, T be the temperature, q be the heat flux, and H be the heat production rate. The above mechanical and thermal boundary conditions will be used in the numerical solution of the partial differential equations.

[0055] Then, the evolution of topography and landforms is realized by solving the topographic diffusion equation and the river erosion rate equation:

[0056] Terrain diffusion equation:

[0057]

[0058] River erosion rate equation:

[0059]

[0060] Where h is elevation, k is topographic diffusion coefficient, Q is flow rate, S is slope, C is the threshold for river erosion, and K, m, and n are constants.

[0061] Finally, the flexural equilibrium settlement of the basement is calculated by solving the flexural equilibrium equation to determine the basement settlement amplitude of the formation model. The flexural equilibrium equation is as follows:

[0062]

[0063] Where D is the flexural stiffness, w is the deflection, q is the load calculated based on crustal thickening, and ρ is the load. m ρ is the density of the mantle. f The density of material filling the flexural depressions above the lithosphere.

[0064] The base settlement amplitude is different from the base settlement parameter in the basic parameters. The base settlement parameter is preset before the simulation, while the base settlement amplitude is calculated during the simulation based on the simulation results of the previous calculation step. The calculated flexural settlement amplitude can be converted into the base settlement velocity of the next step, and the flexural process is realized by setting the vertical velocity boundary conditions of the next step.

[0065] This invention simulates the deformation evolution of a "bidirectional convergence" foreland thrust belt by sequentially and iteratively solving the aforementioned equations. The numerical simulation is achieved through multiple computational steps, each calculating only a short timeframe of evolution. The next step is then calculated based on the results of the previous step, continuing until the expected termination time is reached. Each computational step requires calculating the aforementioned equations; this process constitutes the iterative solution. The mechanical and thermal boundary conditions described above reflect the "bidirectional convergence" characteristic.

[0066] To overcome the oversimplification of surface process models in previous simulations of complex foreland thrust belt structures with multiple detachments, this surface process model has been optimized and improved. In this optimized scheme, surface processes simultaneously consider topographic diffusion and river erosion. Topographic diffusion treats topography as a scalar similar to heat; rocks from higher terrain roll down to lower terrain, and the diffusion rate is proportional to the topographic gradient. However, the entire process is subject to material conservation and is governed by the diffusion equation:

[0067]

[0068] Where h is altitude, t is time, and k is the topographic diffusion coefficient.

[0069] The erosion process of bedrock by rivers is modeled using a river power model, which assumes that the erosion rate of a river is proportional to the power of the river flow and the slope:

[0070]

[0071] Where E is the erosion rate, Q is the river flow, S is the river slope, C is the threshold for erosion, and K, m, and n are constants.

[0072] Meanwhile, to overcome the problem of oversimplified basement settlement models in previous simulations of complex foreland thrust belt structures using the FLAC platform, this technical solution introduces a flexural settlement model. That is, the magnitude of basement settlement is calculated based on crustal thickening, therefore, the flexural equation needs to be solved:

[0073]

[0074] Where D is the flexural stiffness, w is the deflection, q is the load calculated based on crustal thickening, and ρ is the load. m ρ is the density of the mantle. f The density of material filling the flexural depressions above the lithosphere.

[0075] In the data output step, the data obtained from iteratively solving the equations needs to be interpreted to obtain the information represented by the data. One way to do this is to visualize the data. Data visualization involves re-reading the series of result files from the iterative solution of the above equations into the FLAC platform, and then adjusting the display parameters according to the needs of the research to draw corresponding contour plots, such as stress fields, strain fields, temperature fields, and material fields.

[0076] The data output of this invention can also be achieved using other software. For example, by using the file operation function of the fish language within FLAC, the data in the solution results, such as stress, strain rate, temperature, physical properties, and mesh coordinates, can be extracted and written into a text file, and then plotted using other tools, such as Python, Tecplot, and Matlab.

[0077] Another embodiment of the present invention provides a numerical simulation device for foreland thrust belts to implement the above-mentioned method, such as... Figure 3 As shown, the device includes: a basic parameter acquisition module, a formation model construction module, a boundary condition setting module, an equation iterative solution module, and a data output module. Its operation is as follows:

[0078] The basic parameter acquisition module determines and acquires the basic parameters required for the numerical simulation based on the numerical simulation requirements and the geological data of the foreland thrust zone, which is the object of the numerical simulation. These basic parameters may include one or more of the following: stratigraphic model parameters, numerical simulation control parameters, thermal parameters, lithological physical properties, surface processes, and basement subsidence parameters.

[0079] The formation model construction module constructs a formation model based on the formation distribution and well logging data of the numerical simulation object, and sets the formation model based on the basic parameters. Specifically, it sets the lithology, thickness, and morphology of each layer of the formation model, and then assigns physical property parameters to the corresponding lithology. It assembles an initial temperature field to the formation model based on the geothermal gradient, and assembles an initial geostress field to the formation model based on the static rock pressure.

[0080] The boundary condition setting module sets the boundary conditions for the numerical simulation based on the aforementioned basic parameters. Specifically, it sets the thermal and mechanical boundary conditions for the numerical simulation.

[0081] The equation iterative solution module solves the mass conservation equation, momentum conservation equation, and energy conservation equation based on the boundary conditions to obtain the field data of the velocity field, pressure field, and temperature field of the stratigraphic model; solves the topographic diffusion equation and the river erosion rate equation to obtain the topographic evolution data of the stratigraphic model; and solves the flexural equilibrium equation to obtain the basement settlement amplitude of the stratigraphic model, thereby realizing the simulation of the flexural equilibrium settlement process of the basement.

[0082] The data output module outputs the field data, evolution data, and basement settlement magnitude obtained from solving the equations as simulation results. Data interpretation can include using visualization methods.

[0083] The technical effects and other details of the device described in this embodiment can be found in the relevant content of the above method embodiments, and will not be repeated here.

[0084] Another embodiment of the present invention provides a numerical simulation platform for the deformation evolution of complex structures with multiple detachments in foreland thrust belts, comprising: at least one processor; and a memory communicatively connected to the at least one processor. The memory stores instructions executable by the at least one processor, which, when executed, enable the at least one processor to perform the aforementioned numerical simulation method for the deformation evolution of complex structures with multiple detachments in foreland thrust belts.

[0085] The memory and processor are connected via a bus, which can include any number of interconnecting buses and bridges, connecting various circuits of one or more processors and memories. The bus can also connect various other circuits, such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and will not be described further herein. The bus interface provides an interface between the bus and the transceiver. The transceiver can be a single element or multiple elements, such as multiple receivers and transmitters, providing a unit for communicating with various other devices over a transmission medium. Data processed by the processor is transmitted over the wireless medium via an antenna, which further receives data and transmits it to the processor.

[0086] The processor manages the bus and general processing, and also provides various functions, including timing, peripheral interfaces, voltage regulation, power management, and other control functions. Memory is used to store data used by the processor during operation.

[0087] In another embodiment of the present invention, a computer-readable storage medium is provided, storing a computer program. When the computer program is executed by a processor, it implements the method embodiments described above.

[0088] 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 device (which may be a microcontroller, chip, etc.) 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.

[0089] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0090] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0091] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A numerical simulation method for foreland thrust belts, characterized in that, include: Based on the requirements of numerical simulation and the geological data of the foreland thrust belt, which is the object of numerical simulation, the basic parameters required for numerical simulation are determined and obtained. The basic parameters include: stratigraphic model parameters, numerical simulation control parameters, thermal parameters, lithological physical property parameters, surface processes and basement settlement parameters. A formation model is constructed based on the formation distribution and well logging data of the numerical simulation object, and the formation model is set based on the basic parameters. The boundary conditions for the numerical simulation are set based on the aforementioned basic parameters; Based on the boundary conditions, the mass conservation equation, momentum conservation equation, and energy conservation equation are solved to obtain the velocity field, pressure field, and temperature field data of the stratigraphic model; the topographic diffusion equation and river erosion rate equation are solved to obtain the topographic evolution data of the stratigraphic model; and the flexural equilibrium equation is solved to obtain the basement settlement amplitude of the stratigraphic model. Output the field data, the evolution data, and the basement subsidence magnitude.

2. The method according to claim 1, characterized in that, The boundary conditions for the numerical simulation based on the aforementioned basic parameters include: The thermal boundary conditions for numerical simulation are set based on the thermal parameters in the basic parameters. The mechanical boundary conditions for the numerical simulation are set based on the numerical simulation control parameters, surface processes, and basement settlement parameters in the aforementioned basic parameters.

3. The method according to claim 2, characterized in that, The thermal boundary conditions are set as follows: the surface temperature of the ground is constant, the left and right boundaries are adiabatic, and the bottom boundary has a constant heat flux value.

4. The method according to claim 2, characterized in that, The numerical simulation control parameters include: convergence rate and iteration time step; The surface processes and basement subsidence parameters include: the average annual rainfall that determines the rate of surface erosion and the effective elastic thickness that determines the rate of basement subsidence under the same lithosphere thickening conditions.

5. The method according to claim 4, characterized in that, The foreland thrust zone used as the object of numerical simulation is a single foreland thrust zone, and the mechanical boundary conditions are defined as follows: One side boundary is set to be fixed in the horizontal direction, the other side boundary is set to a constant horizontal velocity, the bottom boundary is set to the boundary between a constant vertical velocity and a constant horizontal velocity, and the upper surface is a free surface; Wherein, the vertical velocity is equal to the base settlement velocity; the horizontal velocity is equal to the convergence rate.

6. The method according to claim 4, characterized in that, The foreland thrust zone, used as the object of numerical simulation, is a bilateral convergence model of a mountain range composed of two foreland thrust zones. The mechanical boundary conditions are defined as follows: The left boundary is set with a constant horizontal velocity to the right, the right boundary is set with a constant horizontal velocity to the left, the bottom boundary is set with a constant vertical velocity and constant horizontal velocities in opposite directions on the left and right sides, and the top surface is a free surface. Wherein, the rightward horizontal velocity and the leftward horizontal velocity are both equal to 1 / 2 of the convergence rate; the vertical velocity is equal to the base settlement velocity.

7. The method according to claim 1, characterized in that, Setting the formation model based on the aforementioned basic parameters includes: Based on the stratigraphic model parameters, the lithology, thickness, and morphology of each layer of the stratigraphic model are set; Assign physical property parameters of the lithology to the stratigraphic model; An initial temperature field is assembled into the formation model based on the geothermal gradient in the thermal parameters. An initial geostress field is assembled into the formation model based on the static rock pressure in the basic parameters.

8. The method according to claim 1, characterized in that, The stratigraphic model parameters include: the width and depth of the stratigraphic model, the thickness and lithology of each rock layer, and the horizontal and vertical grid resolution.

9. The method according to claim 1, characterized in that, The thermal parameters include: thermal conductivity, specific heat capacity, coefficient of thermal expansion, geothermal gradient, heat production rate, and crustal heat flow.

10. The method according to claim 1, characterized in that, The physical properties of the lithology include: bulk modulus, shear modulus, density, cohesion, tensile strength, internal friction angle, expansion angle, and viscosity, which correspond to the rock lithology.

11. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method as described in any one of claims 1 to 10.

12. A computer 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 program, it implements the method as described in any one of claims 1 to 10.

13. A numerical simulation device for foreland thrust belts, characterized in that, include: The basic parameter acquisition module is used to determine and acquire the basic parameters required for numerical simulation based on the numerical simulation requirements and the geological data of the foreland thrust belt, which is the object of numerical simulation. The basic parameters include: stratigraphic model parameters, numerical simulation control parameters, thermal parameters, lithological physical property parameters, surface processes and basement settlement parameters. The formation model construction module is used to construct a formation model based on the formation distribution and well logging data of the numerical simulation object, and to set the formation model based on the basic parameters. A boundary condition setting module is used to set the boundary conditions for numerical simulation based on the basic parameters. The equation iterative solution module is used to solve the mass conservation equation, momentum conservation equation, and energy conservation equation based on the boundary conditions to obtain the field data of the velocity field, pressure field, and temperature field of the stratigraphic model; to solve the topographic diffusion equation and the river erosion rate equation to obtain the topographic evolution data of the stratigraphic model; and to solve the flexural equilibrium equation to obtain the basement settlement amplitude of the stratigraphic model. The data output module is used to output the field data, the evolution data, and the basement settlement amplitude.

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