CN116206079B - Geological body modeling method and related equipment based on moving tetrahedron - Google Patents

Abstract

The invention provides a geological body modeling method and related equipment based on moving tetrahedrons, including: obtaining the drilling exploration data in the target area to obtain boundary point information data on the surface of the geological body; constructing an implicit surface function based on the boundary point information data model, and solve the implicit surface function model to obtain the implicit surface function model of the geological body; according to the geological data of the target area and the preset grid resolution, construct multiple cube voxels, and each cube Divide the tetrahedral voxel to obtain multiple tetrahedral voxels; for each tetrahedral voxel, the coordinate values of the four points on the tetrahedral voxel are substituted into the implicit surface function model of the geological body for calculation, and all four-sided voxels are obtained. The implicit surface function values corresponding to the four points on the voxel; all tetrahedral voxels are cut according to each implicit surface function value to obtain the three-dimensional solid model of the geological body in the target area; the modeling accuracy of the geological body is improved and matching.

Description

Geological body modeling method and related equipment based on moving tetrahedron

technical field

The invention relates to the technical field of three-dimensional geological modeling, in particular to a geological body modeling method and related equipment based on moving tetrahedrons.

Background technique

At present, 3D geological modeling has become a popular research object in the field of geological modeling. 2D models cannot display geological conditions conveniently and clearly. Compared with traditional information display methods, 3D geological models can more clearly and intuitively Characterize various environmental conditions of geology. The 3D geological model can characterize the spatial characteristics of geological bodies from different angles, which helps researchers analyze and obtain more geological information.

Implicit surface functions can be used to represent geological surfaces, and there are two main methods to visualize implicit surface functions: surface rendering and volume rendering. The moving tetrahedron algorithm belongs to the first visualization method, the surface rendering method, which characterizes the surface of a geological body by extracting isosurfaces in the implicit surface function. When visualizing the implicit surface function model, the commonly used basic units are cubes, hexahedrons, and tetrahedrons. The basic units are also called voxels, or primitive elements used to represent spaces. The faces of the hexahedron and tetrahedron are usually kept parallel to the coordinate axes. In this case, the geological model established has a rough boundary and is not smooth enough to accurately characterize the geological boundary.

Contents of the invention

The invention provides a geological body modeling method and related equipment based on moving tetrahedron, the purpose of which is to improve the accuracy and matching degree of geological body modeling.

In order to achieve the above object, the present invention provides a method for modeling geological bodies based on mobile tetrahedrons, including:

Step 1, obtaining the drilling exploration data in the target area to obtain the boundary point information data on the surface of the geological body;

Step 2, constructing an implicit surface function model based on the boundary point information data, and solving the implicit surface function model to obtain the implicit surface function model of the geological body;

Step 3, according to the geological data of the target area and the preset grid resolution, construct multiple cube voxels, and divide each cube voxel to obtain multiple tetrahedral voxels;

Step 4. For each tetrahedron voxel, the coordinate values of the four points on the tetrahedron voxel are substituted into the implicit surface function model of the geological body for calculation, and the corresponding four points on all tetrahedron voxels are obtained. The implicit surface function value of ;

Step 5: Cut all the tetrahedral voxels according to the values of the implicit surface functions to obtain the 3D solid model of the geological body in the target area.

Further, step 1 includes:

Obtain borehole exploration data in the target area;

Combined sample analysis is carried out on the drilling exploration data to obtain the lithology samples of the target area;

The adjacent different lithological samples in the target area are processed to obtain the boundary point information data on the surface of the geological body.

Further, before step 5, it also includes:

According to the relationship between the implicit surface function values corresponding to the four points on all tetrahedron voxels and the preset grid size, the four points on all tetrahedron voxels are solved by the central difference method, and the The gradient value corresponding to each point;

The gradient value corresponding to each point is used as the normal vector of the four points on all tetrahedral voxels.

Further, the expression of the central difference method is:

The four points on all tetrahedral voxels are solved by the central difference method, and the gradient value corresponding to each point is obtained:

作为所有四面体体元上四个点位的法向量/>

，/>

为网格序列号，/>

分别为网格在X、Y、Z三个方向上的长度，/>

为隐式曲面函数值的求解表达式。Among them, the gradient value

as the normal vectors of the four points on all tetrahedral voxels />

, />

is the grid serial number, />

are the lengths of the grid in the X, Y, and Z directions respectively, />

Evaluate expression for the value of the implicit surface function.

Further, before step 5, it also includes:

According to the implicit surface function values corresponding to the four points on all tetrahedron voxels, extract equivalent points from all sides of each tetrahedron voxel to obtain a set of equivalent points;

According to the set of isovalue points, the triangular surface is drawn sequentially in each tetrahedron voxel, and the isosurface corresponding to the geological body in the target area is obtained.

Further, step 5 includes:

Define a tetrahedral voxel whose constraint values at four points are greater than zero as an absolute interior tetrahedron,

Define a tetrahedron voxel whose constraint value of at least one point among the four points is less than or equal to zero is a boundary tetrahedron;

Taking the isosurface as the interface, the boundary tetrahedron is tetrahedral cut, and the part of the boundary tetrahedron located inside the implicit surface is obtained;

The part of the absolute internal tetrahedron and the boundary tetrahedron located inside the implicit surface constitutes the 3D solid model of the geological volume in the target area.

Further, after step 5, it also includes:

Using the Euler tetrahedron formula to calculate the three-dimensional solid model of the geological body, the volume of the geological body is obtained.

The present invention also provides a geological body modeling device based on moving tetrahedrons, including:

The obtaining module is used to obtain the drilling exploration data in the target area to obtain the boundary point information data on the surface of the geological body;

The construction module is used for constructing the implicit surface function model based on the boundary point information data, and solving the implicit surface function model to obtain the geological body implicit surface function model;

The division module is used to construct a plurality of cube voxels according to the geological data of the target area and the preset grid resolution, and divide each cube voxel to obtain a plurality of tetrahedron voxels;

The calculation module is used to substitute the coordinate values of the four points on the tetrahedral voxel into the implicit surface function model of the geological body for each tetrahedral voxel, and obtain the four points on all tetrahedral voxels The value of the implicit surface function corresponding to the bit;

The cutting module is used to cut all the tetrahedral voxels according to the values of the implicit surface functions to obtain the three-dimensional solid model of the geological body in the target area.

The present invention also provides a computer-readable storage medium, where a computer program is stored in the computer-readable storage medium, and when the computer program is executed by a processor, the geological body modeling method based on the moving tetrahedron is implemented.

The present invention also provides a terminal device, including a memory, a processor, and a computer program stored in the memory and operable on the processor. When the processor executes the computer program, the geological body modeling method based on moving tetrahedron is realized.

Said scheme of the present invention has following beneficial effect:

The present invention obtains the boundary point information data of the surface of the geological body by acquiring the drilling exploration data of the target area; constructs an implicit surface function model based on the boundary point information data, and solves the implicit surface function model to obtain the implicit surface function of the geological body Model; according to the geological data of the target area and the preset grid resolution, construct a plurality of cubic voxels, and divide each cubic voxel to obtain multiple tetrahedral voxels; for each tetrahedral voxel Substituting the coordinate values of the four points on the tetrahedron voxel into the implicit surface function model of the geological body for calculation, the implicit surface function values corresponding to the four points on all tetrahedron voxels are obtained; Cut all the tetrahedral voxels using the formula surface function value to obtain the 3D solid model of the geological body in the target area; in order to solve the problems of low accuracy and low matching degree of the geological body established in the traditional method, the establishment of the geological body and the actual geological body A more matching geological entity model improves the modeling accuracy and matching degree of geological bodies.

Other beneficial effects of the present invention will be described in detail in the following specific embodiments.

Description of drawings

Fig. 1 is the schematic flow chart of the embodiment of the present invention;

(a) in Figure 2 is a schematic diagram of the first type of equivalent point extraction in the embodiment of the present invention; (b) in Figure 2 is a schematic diagram of the second type of equivalent point extraction in the embodiment of the present invention; (c) in Figure 2 It is a schematic diagram of the third type of equivalent point extraction in the embodiment of the present invention; (d) in Figure 2 is a schematic diagram of the fourth type of equivalent point extraction in the embodiment of the present invention; (e) in Figure 2 is the schematic diagram of the embodiment of the present invention Schematic diagram of the fifth equivalent point extraction situation; (f) in Figure 2 is a schematic diagram of the sixth equivalent point extraction situation of the embodiment of the present invention; (g) in Figure 2 is the seventh equivalent point of the embodiment of the present invention Schematic diagram of the extraction situation; (h) in Figure 2 is a schematic diagram of the extraction of the eighth equivalent point in the embodiment of the present invention; (i) in Figure 2 is a schematic diagram of the extraction of the ninth equivalent point in the embodiment of the present invention; Figure 2 (j) is a schematic diagram of the extraction of the tenth equivalent point in the embodiment of the present invention; (k) in Figure 2 is a schematic diagram of the extraction of the eleventh equivalent point in the embodiment of the present invention; (l) in Figure 2 is Schematic diagram of the twelfth equivalent point extraction situation of the embodiment of the present invention; (m) in Figure 2 is a schematic diagram of the thirteenth equivalent point extraction situation of the embodiment of the present invention; (n) in Figure 2 is an embodiment of the present invention The schematic diagram of the fourteenth equivalence point extraction situation; Fig. 2 (o) is a schematic diagram of the fifteenth equivalence point extraction situation of the embodiment of the present invention; Fig. 2 (p) is the sixteenth equivalence point extraction situation of the embodiment of the present invention Schematic diagram of extraction of equivalence points;

(a) in Fig. 3 is a schematic diagram of the first specific cutting situation based on the moving tetrahedron algorithm in the embodiment of the present invention; (b) in Fig. 3 is a schematic diagram of the second specific cutting situation based on the moving tetrahedron algorithm in the embodiment of the present invention; (c) in Fig. 3 is a schematic diagram of the third specific cutting situation based on the moving tetrahedron algorithm according to the embodiment of the present invention; (d) in Fig. 3 is a schematic diagram of the fourth specific cutting situation based on the moving tetrahedron algorithm according to the embodiment of the present invention; (e) in FIG. 3 is a schematic diagram of the fifth specific cutting situation based on the moving tetrahedron algorithm according to the embodiment of the present invention; (f) in FIG. 3 is a schematic diagram of the sixth specific cutting situation based on the moving tetrahedron algorithm according to the embodiment of the present invention; (g) in Fig. 3 is a schematic diagram of the seventh specific cutting situation based on the moving tetrahedron algorithm according to the embodiment of the present invention; (h) in Fig. 3 is a schematic diagram of the eighth specific cutting situation based on the moving tetrahedron algorithm according to the embodiment of the present invention; (i) in Fig. 3 is a schematic diagram of the ninth specific cutting situation based on the moving tetrahedron algorithm according to the embodiment of the present invention; (j) in Fig. 3 is a schematic diagram of the tenth specific cutting situation based on the moving tetrahedron algorithm according to the embodiment of the present invention; (k) in Figure 3 is a schematic diagram of the eleventh specific cutting situation based on the moving tetrahedron algorithm according to the embodiment of the present invention; (l) in Figure 3 is the twelfth specific cutting situation based on the moving tetrahedron algorithm according to the embodiment of the present invention Schematic diagram; (m) in Figure 3 is a schematic diagram of the thirteenth specific cutting situation based on the moving tetrahedron algorithm in the embodiment of the present invention; (n) in Figure 3 is the fourteenth specific cutting situation based on the moving tetrahedron algorithm in the embodiment of the present invention Schematic diagram of the cutting situation; (o) in Figure 3 is a schematic diagram of the fifteenth specific cutting situation based on the moving tetrahedron algorithm in the embodiment of the present invention; (p) in Figure 3 is the sixteenth cutting situation based on the moving tetrahedron algorithm in the embodiment of the present invention Schematic diagram of a specific cutting situation;

Fig. 4 is a cross-sectional view of a three-dimensional geological solid model constructed in an embodiment of the present invention.

Detailed ways

In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, the following will describe in detail with reference to the drawings and specific embodiments. Apparently, the described embodiments are some, but not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, or in a specific orientation. construction and operation, therefore, should not be construed as limiting the invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and should not be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a locking connection or a detachable connection. Connected, or integrally connected; it can be mechanically connected or electrically connected; it can be directly connected or indirectly connected through an intermediary, and it can be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as there is no conflict with each other.

Aiming at the existing problems, the present invention provides a geological body modeling method based on moving tetrahedron and related equipment.

As shown in Figure 1, the embodiment of the present invention provides a kind of geological body modeling method based on mobile tetrahedron, comprising:

Step 1, obtaining the drilling exploration data in the target area to obtain the boundary point information data on the surface of the geological body;

Step 2, constructing an implicit surface function model based on the boundary point information data, and solving the implicit surface function model to obtain the implicit surface function model of the geological body;

Step 3, according to the geological data of the target area and the preset grid resolution, construct multiple cube voxels, and divide each cube voxel to obtain multiple tetrahedral voxels;

Step 4. For each tetrahedron voxel, the coordinate values of the four points on the tetrahedron voxel are substituted into the implicit surface function model of the geological body for calculation, and the corresponding four points on all tetrahedron voxels are obtained. The implicit surface function value of ;

Step 5: Cut all the tetrahedral voxels according to the values of the implicit surface functions to obtain the 3D solid model of the geological body in the target area.

Specifically, Step 1 includes:

Obtain borehole exploration data in the target area;

Combined sample analysis is carried out on the drilling exploration data to obtain the lithology samples of the target area;

The adjacent different lithological samples in the target area are processed to obtain the boundary point information data on the surface of the geological body.

In the embodiment of the present invention, when performing drilling exploration on the target area, it is necessary to record the data during the exploration process, such as the azimuth, inclination angle, bottom elevation, bottom depth, and layer thickness of the drilling section. hole exploration data; after the completion of the drilling exploration project, these data will be processed and sorted into corresponding histograms, and according to these drilling histograms can be analyzed to obtain the specific location of the borehole, and the drill Hole inclinometer information, sampling conditions, etc. After sorting these data, four related tables can be obtained: drill hole opening table, drill hole inclination data table, drill hole lithology table and drill hole sample analysis table. Combination sample analysis of these data can obtain the formation combination sample table. After a series of collation, analysis, and catalog operations, the lithology and other relevant information of a certain section of drilling can be quickly obtained. The boundary point information data can be obtained by processing the adjacent different lithology sample segments, and the boundary point information data will be used as the initial data.

Specifically, in step 2, the implicit surface function model is constructed based on the boundary point information data, and the implicit surface function model is solved to obtain the implicit surface function model of the geological body, including:

After preprocessing the original borehole exploration data, information such as boundary point set coordinates and normal vectors on the surface of the geological body can be obtained, and these data information can be used as the initial input data for solving the implicit surface function, and a more suitable one can be selected. The implicit surface reconstruction method is used to construct the implicit surface function model of the geological body. The implicit surface reconstruction method used in the embodiment of the present invention is the radial basis implicit surface reconstruction method based on the first-order polynomial, and the implicit surface function equation is constructed and It is solved to obtain the implicit surface function model of the surface of the geological body.

Specifically, in step 3, according to the geological data of the target area and the preset grid resolution, a plurality of cubic voxels are constructed, and each cubic voxel is divided to obtain multiple tetrahedral voxels, including:

Analyze the geological data of the target area, construct cube voxels according to the set grid resolution, and then subdivide the cube one by one, and divide each cube voxel into five tetrahedron voxels.

Specifically, in step 4, for each tetrahedron voxel, the coordinate values of the four points on the tetrahedron voxel are substituted into the implicit surface function model of the geological body for calculation, and the four The implicit surface function value corresponding to points, including:

In the embodiment of the present invention, the coordinate values of the four points on all tetrahedron voxels are respectively substituted into the implicit curved surface function model of the surface of the geological body, and the hidden values corresponding to the four points on all tetrahedron voxels are obtained The value of the implicit surface function; the value of the implicit surface function of each point represents the distance between the point and the implicit surface, and the value of the implicit surface function means that the point is located inside the implicit surface, and the implicit surface function A negative value means that the point is outside the implicit surface, and if the value of the implicit surface function is zero, it means that the point is on the implicit surface.

Specifically, before step 5, it also includes:

According to the relationship between the implicit surface function values corresponding to the four points on all tetrahedron voxels and the preset grid size, the four points on all tetrahedron voxels are solved by the central difference method, and the The gradient value corresponding to each point;

The gradient value corresponding to each point is used as the normal vector of the four points on all tetrahedral voxels.

In the embodiment of the present invention, after obtaining the implicit surface function values corresponding to the four points on all tetrahedral voxels, combined with the set geological body grid size, the central difference method is used to solve the Gradient value, the gradient value corresponding to each point is used as the normal vector of the four points on all tetrahedral voxels, making the established model more continuous and smooth.

Specifically, the expression of the central difference method is:

The four points on all tetrahedral voxels are solved by the central difference method, and the gradient value corresponding to each point is obtained:

作为所有四面体体元上四个点位的法向量/>

，/>

为网格序列号，/>

分别为网格在X、Y、Z三个方向上的长度，/>

为隐式曲面函数值的求解表达式。Among them, the gradient value

as the normal vectors of the four points on all tetrahedral voxels />

, />

is the grid serial number, />

are the lengths of the grid in the X, Y, and Z directions respectively, />

Evaluate expression for the value of the implicit surface function.

Specifically, before step 5, it also includes:

According to the implicit surface function values corresponding to the four points on all tetrahedron voxels, extract equivalent points from all sides of each tetrahedron voxel to obtain a set of equivalent points;

According to the implicit surface function value of each point on the tetrahedron voxel, the intersection of the implicit surface model and the tetrahedron voxel can be analyzed. In the embodiment of the present invention, a tetrahedron voxel is taken as an example to define a tetrahedral voxel The four points on the voxel are p ₁ , p ₂ , p ₃ , p ₄ , then there are sixteen situations of the relationship between the implicit surface function model and the tetrahedral voxel, as shown in Figure 2, ( The implicit function values of the four points in a) are all greater than zero, then the tetrahedron is located inside the implicit surface, and there is no equivalent point; in (b) the implicit function value of p ₁ is less than zero, p ₂ , p ₃ , If the implicit function value of p ₄ is greater than zero, the equivalent points c, a, and b on p ₁ p ₂ , p ₁ p ₃ , and p ₁ p ₄ are respectively extracted, and c, a, and b are used as triangle vertices to form Isosurface; in (c), the implicit function value of p ₂ is less than zero, and the implicit function value of p ₁ , p ₃ , p ₄ is greater than zero, then p ₁ p ₂ , p ₂ p ₃ , p ₃ are extracted respectively The equivalence points c, a, b on p ₄ , with c, a, b as the vertices of the triangle, constitute the isosurface; the implicit function value of p ₃ in (d) is less than zero, p ₁ , p ₂ , p ₄ If the value of the implicit function is greater than zero, the equivalent points a, b, and c on p ₁ p ₃ , p ₂ p ₃ , and p ₃ p ₄ are respectively extracted, and a, b, and c are used as triangle vertices to form the equivalent surface; in (e), the implicit function value of p ₄ is less than zero, and the implicit function values of p ₁ , p ₂ , p ₃ are greater than zero, then p ₁ p ₄ , p ₂ p ₃ , p ₃ p ₄ are extracted respectively The equivalence points c, b, a on , with c, b, a as triangle vertices, constitute the isosurface; in (f), the implicit function values of p ₁ , p ₂ are less than zero, and the implicit function values of p ₃ , p ₄ If the value of the formula function is greater than zero, the equivalent points a, b, c, d on p ₁ p ₃ , p ₂ p ₃ , p ₂ p ₄ , p ₁ p ₄ are respectively extracted, and a, b, c, d As the vertices of a quadrilateral, it forms an isosurface; in (g), the implicit function values of p ₁ and p ₃ are less than zero, and the implicit function values of p ₂ and p ₄ are greater than zero, then p ₁ p ₂ and p ₂ are extracted respectively Equivalent points a, b, c, d on p ₃ , p ₃ p ₄ , p ₁ p ₄ , take a, b, c, d as quadrilateral vertices to form an isosurface; in (h) p ₁ , p The implicit function value of ₄ is less than zero, and the implicit function values of p ₂ and p ₃ are greater than zero, then the equivalent points on p ₁ p ₂ , p ₁ p ₃ , p ₃ p ₄ , and p ₁ p ₄ are extracted respectively a, b, c, d, take a, b, c, d as the vertices of the quadrilateral to form an isosurface; (i) the implicit function values of p ₂ and p ₃ are less than zero, and the implicit function values of p ₁ and p ₄ If the value is greater than zero, the equivalent points a, b, c, and d on p ₁ p ₃ , p ₁ p ₂ , p ₂ p ₄ , and p ₁ p ₂ are respectively extracted, and a, b, c, and d are used as quadrilaterals The vertices constitute the isosurface; in (j), the implicit function values of p ₂ and p ₄ are less than zero, and the implicit function values of p ₁ and p ₃ are greater than zero, then p ₁ p ₂ and p ₂ p ₃ are extracted respectively , p ₃ p ₄ , p ₁ p ₄ are the equivalent points a, b, c, d, with a, b, c, d as the vertices of the quadrilateral to form an isosurface; in (k) p ₃ , p ₄ The value of the implicit function is less than zero, _{and the value} of the _implicit function _of p ₁ and _{p 2 is} greater than zero, then _the equivalent points a, b, c, d, with a, b, c, d as the vertices of the quadrilateral to form an isosurface; in (l), the implicit function values of p ₁ , p ₂ , p ₃ are less than zero, and the implicit function value of p ₄ is greater than zero, extract the equivalent points c, b, and a on p ₁ p ₄ , p ₂ p ₄ , and p ₃ p ₄ respectively, and use c, b, and a as triangle vertices to form an isosurface; (m) The implicit function value of p ₁ , p ₂ , p ₄ is less than zero, and the implicit function value of p ₃ is greater than zero, then the equivalent point a on p ₁ p ₃ , p ₂ p ₃ , p ₃ p ₄ is extracted respectively , b, c, with a, b, c as the vertices of the triangle to form an isosurface; in (n), the implicit function value of p ₁ , p ₃ , p ₄ is less than zero, and the implicit function value of p ₂ is greater than zero, Then extract the equivalent points c, a, b on p ₁ p ₂ , p ₂ p ₃ , p ₂ p ₄ respectively, and use c, a, b as triangle vertices to form an iso-value surface; in (o) p ₂ , p ₃ , p ₄ whose implicit function value is less than zero, and the implicit function value of p ₁ is greater than zero, then the equivalent points c and a on p ₁ p ₂ , p ₁ p ₃ , p ₁ p ₄ are respectively extracted , b, with c, a, b as the vertices of the triangle to form an isosurface; if the implicit function values of the four points in (p) are all less than zero, then the tetrahedron is located outside the implicit surface and has no equivalent points; Equivalence points are extracted from each side of the tetrahedron voxel, and all tetrahedron voxels are traversed in turn to extract equivalent points to obtain a final set of equivalent points. In the process of extracting the equivalent points, the linear interpolation method is used. In the case of obtaining the implicit function value of the equivalent points to be extracted, according to the position coordinates X , Y , The Z normal vector and the corresponding implicit surface function value are linearly interpolated to obtain the X , Y , Z coordinates and normal vector of the equivalent point. The linear interpolation formula is:

为等值点坐标值，/>

、/>

为等值点所在直线两端点的坐标值，/>

为提取等值面的阈值，/>

为隐式曲面函数的求解表达式；in,

is the coordinate value of the equivalent point, />

, />

is the coordinate value of the two ends of the straight line where the equivalent point is located, />

is the threshold for extracting the isosurface, />

is the solution expression of the implicit surface function;

According to the set of isovalue points, the triangular surface is drawn sequentially in each tetrahedron voxel, and the isosurface corresponding to the geological body in the target area is obtained.

Specifically, step 5 includes:

In the embodiment of the present invention, tetrahedron cutting and tetrahedron extraction inside the implicit curved surface are carried out. When it is judged that the implicit curved surface passes through the tetrahedral voxel, the tetrahedral voxel is cut on the basis of extracting the isosurface to obtain Basic units such as tetrahedron and triangular prism. There are sixteen kinds of tetrahedral voxel cutting, and the cutting methods are shown in Figure 3. The sixteen cutting diagrams from (a)-(p) in Figure 3 are the same as those in Figure 2 (a)-(p). The six equivalence point extraction situations correspond one by one.

Cut the tetrahedron and extract the internal tetrahedron according to the implicit surface function values of the four points of the regular tetrahedron; first, define the tetrahedral voxel element whose constraint values at the four points are greater than zero as the absolute internal tetrahedron, define The tetrahedral voxel whose constraint value of at least one point among the four points is less than or equal to zero is the boundary tetrahedron; the isosurface is used as the interface to cut the boundary tetrahedron by tetrahedron, and the boundary tetrahedron is located in the implicit The part outside the surface and the part inside the implicit surface; keep the part of the boundary tetrahedron inside the implicit surface, complete the segmentation of the boundary tetrahedron, and then determine the tetrahedron whose four points are all inside the implicit surface as the absolute The tetrahedron, the absolute internal tetrahedron and the part of the boundary tetrahedron located inside the implicit surface constitute the 3D solid model of the geological body in the target area. The cross-sectional view of the 3D solid model of the geological body is shown in Figure 4.

Specifically, after step 5, also include:

Using the Euler tetrahedron formula to calculate the three-dimensional solid model of the geological body, the volume of the geological body is obtained.

In the embodiment of the present invention, the volume of the geological body is:

The constructed three-dimensional solid model of geological body is composed of voxels such as tetrahedron and triangular prism;

For tetrahedral voxels, use the Euler tetrahedron formula to calculate the volume of the tetrahedron;

For the triangular prism voxel, first divide the triangular prism voxel into three tetrahedral voxels, and then use the Euler tetrahedron formula to calculate the volume of the triangular prism.

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，/>

，四面体O-ABC的六条棱长分别为1、m、n、p、q、r，则四面体的体积计算公式为：The formula for calculating the volume of the Euler tetrahedron is based on the memorized calculation of the lengths of the six sides of the tetrahedron element to obtain the volume of the tetrahedron; the origin is defined as O, and the coordinates of points A, B, and C are respectively

, />

, />

, the lengths of the six edges of the tetrahedron O-ABC are 1, m, n, p, q, r respectively, then the formula for calculating the volume of the tetrahedron is:

Calculate and sum the volumes of all tetrahedrons and triangular prisms according to the above formula, and finally obtain the volume of the geological body.

In the embodiment of the present invention, the boundary point information data on the surface of the geological body is obtained by acquiring the drilling exploration data in the target area; the implicit surface function model is constructed based on the boundary point information data, and the implicit surface function model is solved to obtain the implicit surface function model of the geological body. Surface function model; according to the geological data of the target area and the preset grid resolution, construct multiple cubic voxels, and divide each cubic voxel to obtain multiple tetrahedral voxels; for each tetrahedral voxel respectively Volume element, the coordinate values of the four points on the tetrahedron voxel are substituted into the implicit surface function model of the geological body for calculation, and the implicit surface function values corresponding to the four points on all tetrahedron voxels are obtained; according to Each implicit surface function value cuts all tetrahedral voxels to obtain the 3D solid model of the geological body in the target area; to solve the problems of low precision and low matching degree of the geological body in the traditional method, the establishment and actual The geological entity model that matches the geological body better improves the modeling accuracy and matching degree of the geological body.

The embodiment of the present invention also provides a geological body modeling device based on moving tetrahedrons, including:

The obtaining module is used to obtain the drilling exploration data in the target area to obtain the boundary point information data on the surface of the geological body;

The construction module is used for constructing the implicit surface function model based on the boundary point information data, and solving the implicit surface function model to obtain the geological body implicit surface function model;

The division module is used to construct a plurality of cube voxels according to the geological data of the target area and the preset grid resolution, and divide each cube voxel to obtain a plurality of tetrahedron voxels;

The calculation module is used to substitute the coordinate values of the four points on the tetrahedral voxel into the implicit surface function model of the geological body for each tetrahedral voxel, and obtain the four points on all tetrahedral voxels The value of the implicit surface function corresponding to the bit;

The cutting module is used to cut all the tetrahedral voxels according to the values of the implicit surface functions to obtain the three-dimensional solid model of the geological body in the target area.

It should be noted that the information interaction and execution process between the above-mentioned devices/units are based on the same idea as the method embodiment of the embodiment of the present invention, and its specific functions and technical effects can be found in the method embodiment. part, which will not be repeated here.

Those skilled in the art can clearly understand that for the convenience and brevity of description, only the division of the above-mentioned functional units and modules is used for illustration. In practical applications, the above-mentioned functions can be assigned to different functional units, Completion of modules means that the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiment may be integrated into one processing unit, or each unit may exist separately physically, or two or more units may be integrated into one unit, and the above-mentioned integrated units may adopt hardware It can also be implemented in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the protection scope of the embodiments of the present invention. For the specific working processes of the units and modules in the above system, reference may be made to the corresponding processes in the aforementioned method embodiments, and details will not be repeated here.

The embodiment of the present invention also provides a computer-readable storage medium, where a computer program is stored in the computer-readable storage medium, and when the computer program is executed by a processor, a geological body modeling method based on a moving tetrahedron is realized.

If the integrated unit is realized in the form of a software function unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the embodiment of the present invention implements all or part of the processes in the methods of the above embodiments, which can be completed by instructing related hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, it can realize the steps of the above-mentioned various method embodiments. Wherein, the computer program includes computer program code, and the computer program code may be in the form of source code, object code, executable file or some intermediate form. The computer-readable medium may at least include: any entity or device capable of carrying computer program codes to a construction device/terminal device, a recording medium, a computer memory, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), electrical carrier signal, telecommunication signal and software distribution medium. Such as U disk, mobile hard disk, magnetic disk or CD, etc. In some jurisdictions, computer readable media may not be electrical carrier signals and telecommunication signals under legislation and patent practice.

An embodiment of the present invention also provides a terminal device, including a memory, a processor, and a computer program stored in the memory and operable on the processor. When the processor executes the computer program, the geological body modeling method based on the mobile tetrahedron is implemented. .

It should be noted that the terminal device may be a mobile phone, a tablet computer, a notebook computer, an ultra-mobile personal computer (UMPC, Ultra-mobile Personal Computer), a netbook, a personal digital assistant (PDA, PersonalDigital Assistant) and other terminal devices, for example, a terminal The device can be a station (ST, STION) in a WLAN, a cellular phone, a cordless phone, a Session Initiation Protocol (SIP, Session Initiation Protocol) phone, a wireless local loop (WLL, Wireless Local Loop) station, a personal digital processing ( PDA, Personal Digital Assistant) device, handheld device with wireless communication function, computing device or other processing device connected to a wireless modem, computer, laptop computer, handheld communication device, handheld computing device, satellite wireless device, etc. The embodiment of the present invention does not impose any limitation on the specific type of the terminal device.

The so-called processor can be a central processing unit (CPU, Central Processing Unit), and the processor can also be other general-purpose processors, a digital signal processor (DSP, Digital Signal Processor), an application specific integrated circuit (ASIC, Application Specific Integrated Circuit ), off-the-shelf programmable gate array (FPGA, Field-Programmable Gate Array) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor, or the processor may be any conventional processor, or the like.

In some embodiments, the storage may be an internal storage unit of the terminal device, such as a hard disk or memory of the terminal device. In other embodiments, the memory may also be an external storage device of the terminal device, such as a plug-in hard disk equipped on the terminal device, a smart memory card (SMC, Smart Media Card), a secure digital (SD, Secure Digital) card, flash memory card (Flash Card), etc. Further, the memory may also include both an internal storage unit of the terminal device and an external storage device. The memory is used to store operating system, application program, boot loader (BootLoader), data and other programs, such as the program code of the computer program. The memory can also be used to temporarily store data that has been output or will be output.

It should be noted that the information interaction and execution process between the above-mentioned devices/units are based on the same concept as the method embodiment in the embodiment of the present invention, and its specific functions and technical effects can be found in the method implementation The example part is not repeated here.

The above description is a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications can also be made. It should be regarded as the protection scope of the present invention.

Claims (10)

1. A mobile tetrahedron-based geologic body modeling method, comprising:

step 1, acquiring drilling exploration data of a target area to obtain boundary point information data of the surface of a geologic body;

step 2, an implicit surface function model is built based on the boundary point information data, and the implicit surface function model is solved to obtain a geological implicit surface function model;

step 3, constructing a plurality of cube elements according to the geological data of the target area and the preset grid resolution, and dividing each cube element to obtain a plurality of tetrahedron elements;

step 4, substituting coordinate values of four points on each tetrahedron element into the implicit curved surface function model of the geologic body for calculation to obtain implicit curved surface function values corresponding to the four points on all tetrahedron elements;

and 5, cutting all tetrahedral elements according to the function values of each implicit curved surface to obtain a geological three-dimensional entity model of the target area.

2. The mobile tetrahedron-based geobody modeling method of claim 1, wherein step 1 comprises:

acquiring borehole exploration data of a target area;

carrying out combined sample analysis on the drilling exploration data to obtain lithology samples of a target area;

and processing different adjacent lithology samples in the target area to obtain boundary point information data of the surface of the geologic body.

3. The mobile tetrahedron-based geobody modeling method of claim 1, further comprising, prior to said step 5:

according to the relation between the implicit surface function values corresponding to the four points on all tetrahedron elements and the preset grid size, solving the four points on all tetrahedron elements by a central difference method to obtain gradient values corresponding to the points;

and taking the gradient value corresponding to each point position as the normal vector of four point positions on all tetrahedron elements.

4. A mobile tetrahedron-based geobody modeling method according to claim 3, wherein the expression of the central difference method is:

；

solving four points on all tetrahedron elements by a central difference method to obtain gradient values corresponding to the points as follows:

；

wherein the gradient value

Normal vector as four points on all tetrahedrons +.>

，/>

For the grid serial number>

The length of the grid in the three directions X, Y, Z, respectively,>

is a solving expression of the implicit surface function value.

5. A mobile tetrahedron-based geobody modeling method according to claim 3, further comprising, prior to said step 5:

according to implicit surface function values corresponding to four points on all tetrahedron elements, respectively extracting equivalent points on all sides of each tetrahedron element to obtain an equivalent point set;

and according to the contour point set, triangular surface patch drawing is sequentially carried out in each tetrahedron element, and a contour surface corresponding to the geologic body of the target area is obtained.

6. The mobile tetrahedron-based geobody modeling method of claim 5, wherein said step 5 comprises:

defining tetrahedral elements with constraint values of four points being greater than zero as absolute internal tetrahedrons,

defining tetrahedral elements with constraint values smaller than or equal to zero in at least one of the four points as boundary tetrahedrons;

cutting tetrahedrons on the boundary tetrahedrons by taking the isosurface as an interface to obtain a part of the boundary tetrahedrons positioned in the implicit curved surface;

and the absolute internal tetrahedron and the part of the boundary tetrahedron, which is positioned in the implicit curved surface, form a geological body three-dimensional entity model of the target area.

7. The mobile tetrahedron-based geobody modeling method of claim 6, further comprising, after step 5:

and calculating the three-dimensional solid model of the geologic body by using an Euler tetrahedral formula to obtain the volume of the geologic body.

8. A mobile tetrahedron-based geologic body modeling apparatus, comprising:

the acquisition module is used for acquiring drilling exploration data of the target area to obtain boundary point information data of the surface of the geologic body;

the construction module is used for constructing an implicit curved surface function model based on the boundary point information data, and solving the implicit curved surface function model to obtain a geological implicit curved surface function model;

the dividing module is used for constructing a plurality of cube elements according to the geological data of the target area and the preset grid resolution, and dividing each cube element to obtain a plurality of tetrahedron elements;

the calculation module is used for substituting coordinate values of four points on each tetrahedron element into the geological implicit surface function model for calculation to obtain implicit surface function values corresponding to the four points on all the tetrahedron elements;

and the cutting module is used for cutting all tetrahedral elements according to the function values of each implicit curved surface to obtain a geological three-dimensional entity model of the target area.

9. A computer readable storage medium storing a computer program, wherein the computer program when executed by a processor implements the mobile tetrahedron based geobody modeling method according to any one of claims 1 to 7.

10. A terminal device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that the processor implements the mobile tetrahedron based geobody modeling method according to any one of claims 1 to 7 when the computer program is executed.

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