A method and device for constructing a parametric three-dimensional model of a fold structure

Abstract

The present invention discloses a method and device for constructing a parametric three-dimensional model of a fold structure. The method includes: (1) obtaining the fold parameters set by the user to form a fold hinge parameter set A, a fold element parameter set F, and a formation thickness set S; (2) generating a reference formation boundary sl0 of the fold intermediate section based on the fold element parameter set F and storing it in the formation boundary set SL; (3) generating the remaining formation boundaries of the intermediate section according to the formation thickness set S and the reference formation boundary sl0 according to the fold formation arrangement rule and storing them in the formation boundary set SL; (4) converting the formation boundary set SL of the intermediate section into an intermediate section sc mid ; (5) generating a set of profiles SC of the fold in the hinge direction through affine transformation processing based on the intermediate section sc mid and the fold hinge parameter set A; (6) generating a symbolic three-dimensional model of the fold through the Morphing interpolation algorithm. The present invention has higher efficiency and higher flexibility.

Description

Technical Field

[0001] The invention relates to geographic information technology, and in particular to a method and device for constructing a parameterized three-dimensional model of a fold structure. Background Art

[0002] Folds are wavy bending phenomena of layered rocks in the earth's crust due to the effect of compression. As a basic type of geological structure, fold structure requires both three-dimensional modeling and symbolic expression. However, most of the current three-dimensional modeling methods for fold structures are non-parametric modeling methods that rely on drilling or measured profiles. They not only have a high dependence on geological data, but also have a limited scope of application and low modeling efficiency. On the other hand, the current symbolic expression of fold structures is mostly limited to the two-dimensional level, which is difficult to meet the geological symbol requirements in three-dimensional geological models. Summary of the invention

[0003] Purpose of the invention: In view of the problems existing in the prior art, the present invention provides a more efficient method and device for constructing a parametric three-dimensional model of a pleated structure.

[0004] Technical solution: The method for constructing a parameterized three-dimensional model of a fold structure according to the present invention comprises:

[0005] (1) Obtaining the fold parameters set by the user to form a fold hinge parameter set A, a fold element parameter set F, and a stratum thickness set S;

[0006] (2) Based on the fold element parameter set F, generate the reference stratigraphic boundary sl0 of the fold middle section and store it in the stratigraphic boundary set SL;

[0007] (3) Based on the formation thickness set S and the reference formation boundary sl0, according to the arrangement law of the fold formation, the remaining formation boundaries of the intermediate section are generated and stored in the formation boundary set SL;

[0008] (4) Convert the stratigraphic boundary set SL of the intermediate section into the intermediate section sc mid ;

[0009] (5) Based on the intermediate section sc mid and the fold hinge parameter set A, through affine transformation processing, generate the cross-section set SC of the fold in the hinge direction;

[0010] (6) Based on the section set SC, a symbolic three-dimensional fold model is generated through the Morphing interpolation algorithm.

[0011] Furthermore, step (1) comprises:

[0012] (1-1) Read the fold hinge parameters set by the user, including the hinge front and rear inclination angle, the hinge front and rear direction, the axial front and rear inclination angle and the hinge width, and store them in the fold hinge parameter set A;

[0013] (1-2) Read the fold element parameters set by the user, including the left turning point position, the right turning point position, the axial inclination angle, the wing angle and the fold shape, and store them in the fold element parameter set F;

[0014] (1-3) Read the stratum thickness set by the user and store it in the stratum thickness set S = {s k |k=1,2,...,SN}, where s k It indicates the thickness of the kth stratum from top to bottom set by the user, and SN indicates the number of strata.

[0015] Furthermore, step (2) includes:

[0016] (2-1) Obtain the left turning point position f in the fold element parameter set F pl and the right inflection point position f pr , generating the left turning point p of the fold element l and the right turning point p r , and store the reference stratigraphic boundary point set P0 of the middle section of the fold;

[0017] (2-2) Read the axial inclination angle, inter-wing angle and fold morphological parameters of the fold element in the fold element parameter set F, and record them as γ, δ and curve respectively;

[0018] (2-3) Calculate the inclination angles α and β of the left and right turning ends according to the following formula:

[0019]

[0020] (2-4) According to the inflection point p l and p r , and the inclination angles α and β, the vertex on the axial surface of the fold element is obtained by the point-slope intersection method, which is recorded as vertex C;

[0021] (2-5) According to the axial inclination angle γ and the vertex C, calculate the axis and the bottom line p of the fold element l p r The intersection point D is taken as the vertex D under the axial plane;

[0022] (2-6) Axial plane CD is generated based on vertex C and vertex D, and the turning point E of the wrinkle element is obtained on the axial plane CD. The turning point makes the following equation true:

[0023]

[0024] (2-7) Draw FG⊥CD through point E, intersecting p lC.p r C is at Bezier control points F and G;

[0025] (2-8) are based on point p l , F, E and points E, G, p r , generate two continuous Bezier curve point sets and store them in the reference stratigraphic boundary point set P0;

[0026] (2-9) Based on the maximum rotation angle amax and the rotation radius R set by the user, the reference stratigraphic boundary point set P0 is distorted and deformed to obtain the deformed point set P′0 so that it is closer to the actual stratigraphic distribution when depicting the inverted stratigraphy;

[0027] (2-10) The deformation point set P′0 is converted into the corresponding reference stratigraphic boundary sl0 and stored in the stratigraphic boundary set SL.

[0028] Further, step (2-9) comprises:

[0029] (2-9-1) Select any point p from the reference stratigraphic boundary point set P0 m,0 ;

[0030] (2-9-2) Calculate p m,0 The distance from point D is denoted as r;

[0031] (2-9-3) Calculate point p according to the following formula m,0 The rotation angle θ at:

[0032] θ=amax×(Rr) / R

[0033] (2-9-4) point p m,0 Rotate θ to get the distorted point p′ m,0 , and store it in the deformation point set P′0;

[0034] (2-9-5) Loop through steps (2-9-1) to (2-9-4) until all points in P0 are deformed, and the deformation point set P′0 = {p′ m,0 |m=1,2,...,PN}, PN represents the number of points of the reference stratigraphic boundary.

[0035] Furthermore, step (3) includes:

[0036] (3-1) Set k = 0, where 0 is the serial number of the reference stratigraphic boundary sl0;

[0037] (3-2) Select the formation thickness s from the formation thickness set S k ;

[0038] (3-3) Obtaining the formation thickness s k The stratigraphic boundary of the corresponding stratum slk The point set P k ;

[0039] (3-4) Select the point set P k Any point p in v,k ;

[0040] (3-5) Calculate point p based on adjacent points v,k The tangent direction near the tangent direction is calculated based on the tangent direction. v,k The normal inclination angle ω at

[0041] (3-6) Based on the inclination angle ω and the formation thickness s k Calculate p according to the following formula v,k The corresponding point p in the bottom boundary of the corresponding stratum v,k+1 The coordinates (x v,k+1 ,y v,k+1 ), and store it in the point set P k+1 :

[0042]

[0043] (3-7) Repeat steps (3-4) to (3-6) until P k After traversing all the points in, we get the point set P k+1 ={p v,k+1 |v=1,2,...,PN}, and the point set P k+1 Transformed into stratigraphic boundary sl k+1 , stored in the stratigraphic boundary set SL, PN represents the number of points of the reference stratigraphic boundary;

[0044] (3-8) Determine whether k = SN. If not, k = k + 1 and return to step (3-2). Otherwise, terminate the iteration and obtain the stratum boundary set SL = {sl k |k=0,1,2,...,SN}, SN represents the number of strata.

[0045] Further, step (5) includes:

[0046] (5-1) Obtain the hinge front-back inclination angle and hinge front-back strike of the middle section from the fold hinge parameter set A, and record them as η1, η2;

[0047] (5-2) Read the distance between the section to be generated and the middle section in the fold hinge parameter set A and store it in the set DST = {dst l |l=1,2,...,n}, where dst l represents the distance between the lth section to be generated and the middle section, and n represents the number of sections to be inserted and generated;

[0048] (5-3) Select any section distance dst l ;

[0049] (5-4) Based on η1, η2, and dst l , calculate the profile scaling coefficients scale1 and scale2 in the front and rear directions according to the following formula, and then obtain the affine transformation matrices T1 and T2;

[0050]

[0051]

[0052]

[0053] In the formula, CD mid Represents the middle section sc mid Length of the axial surface;

[0054] (5-5) According to the middle section sc mid , affine transformation matrix T1 or T2, according to the following formula for sc mid Perform matrix operations on each point in the matrix to generate the corresponding section sc l , and store it in the profile collection SC:

[0055]

[0056] Among them, x, y, and z are the middle section sc mid The three-axis coordinates of any point in the equation, x′, y′, and z′ are the three-dimensional coordinates of the corresponding point of the front or rear section respectively. T is substituted into T1 or T2 according to the position of the section to be calculated. When calculating the front section, it is substituted into T1, and when calculating the rear section, it is substituted into T2.

[0057] (5-6) Repeat steps (5-3) to (5-5) until all sections are generated, and obtain the section set SC = {sc l |l=1,2,...,n}.

[0058] Further, step (6) comprises:

[0059] (6-1) According to the profile set SC, the geological boundaries of each profile are obtained, and based on the starting and ending points and the middle points of the geological boundaries of each profile, three constraint boundaries are generated by Lagrange interpolation and stored in the constraint boundary set CL for Morphing interpolation of each layer = {cl k |k=1,2,...,SN}, SN represents the number of strata, cl k represents the kth constraint boundary;

[0060] (6-2) Take any constrained boundary line cl of a stratum k And generate the corresponding three-dimensional point set P3D through the Morphing interpolation algorithm k ;

[0061] (6-3) Using three-dimensional point set P3D k A three-dimensional model of the kth layer of folds is formed;

[0062] (6-4) Execute steps (6-2)-(6-3) repeatedly until the three-dimensional fold model of each layer is completed;

[0063] (6-5) Output the model results as a model file in obj format and bind the corresponding material.

[0064] The device for constructing a parameterized three-dimensional model of a pleated structure of the present invention comprises a processor and a computer program stored in a memory and executable on the processor, and the method is implemented when the processor executes the program.

[0065] The device for constructing a parameterized three-dimensional model of a pleated structure of the present invention comprises a processor and a computer program stored in a memory and executable on the processor, and the method is implemented when the processor executes the program.

[0066] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: based on the various fold parameters set by the user, the present invention generates fold side faces through a contour line comparison algorithm on the basis of generating profiles at different positions, thereby realizing parametric modeling of fold structures. The present invention can construct different types of symbolic fold models according to parameter adjustment, and has high accuracy and a more flexible scope of application while ensuring modeling efficiency, and has important research significance and application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 It is a flow chart of the method for constructing a parameterized three-dimensional model of a fold structure provided by the present invention;

[0068] Figure 2 It is the diagram of the solution process of the turning end point E of the fold profile and the Bezier control points F and G;

[0069] Figure 3 is the intermediate cross-section generation result of the oblique fold in this embodiment;

[0070] Figure 4 It is the Morphing constraint boundary in the front, middle and back sections of the oblique fold and the first stratum in this embodiment;

[0071] Figure 5 is the modeling result of the oblique wrinkles in this embodiment;

[0072] Figure 6 The axial distortion processing and modeling results of the inverted folds by the present invention are shown in FIG. 1 , wherein (a) the original cross section of the inverted folds, (b) the cross section of the inverted folds after distortion processing, and (c) the modeling results of the inverted folds;

[0073] Figure 7 The modeling results of folds divided by the shape of turning ends; (a) sharp edge folds, (b) arc folds, (c) box folds;

[0074] Figure 8 These are the modeling results of folds divided according to cross-sectional morphology; (a) tight folds, (b) closed folds, (c) open folds, and (d) gentle folds. DETAILED DESCRIPTION

[0075] This embodiment discloses a method for constructing a parameterized three-dimensional model of a fold structure. Figure 1 As shown, including:

[0076] (1) Obtain the fold parameters set by the user to form a fold hinge parameter set A, a fold element parameter set F, and a stratum thickness set S.

[0077] This step specifically includes:

[0078] (1-1) Read the fold hinge parameters set by the user, including the hinge front and rear inclination angle, the hinge front and rear direction, the axial front and rear inclination angle and the hinge width, and store them in the fold hinge parameter set A;

[0079] (1-2) Read the fold element parameters set by the user, including the left turning point position, the right turning point position, the axial inclination angle, the wing angle and the fold shape, and store them in the fold element parameter set F;

[0080] (1-3) Read the stratum thickness set by the user and store it in the stratum thickness set S = {s k |k=1,2,...,SN}, where s k It indicates the thickness of the kth stratum from top to bottom set by the user, and SN indicates the number of strata.

[0081] As shown in Table 1, the relevant parameters of the skewed equal-thickness wrinkles with low cylindricity are selected as experimental data in this embodiment.

[0082] Table 1 User setting parameter information table

[0083]

[0084] (2) Based on the fold element parameter set F, generate the reference stratigraphic boundary sl0 of the fold middle section and store it in the stratigraphic boundary set SL.

[0085] This step specifically includes:

[0086] (2-1) Obtain the left turning point position f in the fold element parameter set F pl and the right inflection point position f pr , generating the left turning point p of the fold element l and the right turning point p r , and store the reference stratigraphic boundary point set P0 of the middle section of the fold; in this embodiment, f pl is (0,0,0), f pr is (100,0,0);

[0087] (2-2) Read the axial inclination angle, inter-wing angle and fold morphology parameters of the fold element in the fold element parameter set F, and record them as γ, δ and curve respectively; in this embodiment, γ is 80°, δ is 60°, and curve is 1.5;

[0088] (2-3) Calculate the inclination angles α and β of the left and right turning ends according to the following formula:

[0089]

[0090] In this embodiment, α is 50° and β is 70°;

[0091] (2-4) According to the inflection point p l and p r , and the inclination angles α and β, the vertex on the axial surface of the fold element is obtained by the point-slope intersection method, which is recorded as vertex C;

[0092] (2-5) According to the axial inclination angle γ and the vertex C, calculate the axis and the bottom line p of the fold element l p r The intersection point D is taken as the vertex D under the axial plane;

[0093] (2-6) Generate axial plane CD based on vertex C and vertex D, and obtain the turning point E of the wrinkle element on axial plane CD, as shown in Figure 2 As shown, this turning point makes the following equation true:

[0094]

[0095] (2-7) Draw FG⊥CD through point E, intersecting p l C.p r C is at Bezier control points F and G; Figure 2 As shown;

[0096] (2-8) are based on point p l , F, E and points E, G, p r , generate two continuous Bezier curve point sets and store them in the reference stratigraphic boundary point set P0;

[0097] (2-9) Based on the maximum rotation angle amax and rotation radius R set by the user, the reference stratigraphic boundary point set P0 is distorted and deformed to obtain the deformed point set P′0 so that it is closer to the actual stratigraphic distribution when depicting the inverted stratigraphy; in this embodiment, amax is 60° and R is 100 meters; the specific steps are: (2-9-1) Select any point p in the reference stratigraphic boundary point set P0 m,0 ; (2-9-2) Calculate p m,0 The distance from point D is denoted as r; (2-9-3) Calculate point p according to the following formula m,0 The rotation angle θ at point p is: θ = amax × (Rr) / R, (2-9-4) m,0 Rotate θ to get the distorted point p′ m,0 , and store it in the deformation point set P′0; (2-9-5) loop through steps (2-9-1)-(2-9-4) until all points in P0 are deformed, and the deformation point set P′0={p′ m,0 |m=1,2,...,PN}, PN represents the number of points of the reference stratum boundary, and PN in this embodiment is 21;

[0098] (2-10) The deformation point set P′0 is converted into the corresponding reference stratigraphic boundary sl0 and stored in the stratigraphic boundary set SL.

[0099] (3) Based on the stratigraphic thickness set S and the reference stratigraphic boundary sl0, the remaining stratigraphic boundaries of the intermediate section are generated according to the arrangement law of the fold stratigraphic layers and stored in the stratigraphic boundary set SL.

[0100] This step includes:

[0101] (3-1) Set k = 0, where 0 is the serial number of the reference stratigraphic boundary sl0;

[0102] (3-2) Select the formation thickness s from the formation thickness set S k ;

[0103] (3-3) Obtaining the formation thickness s k The stratigraphic boundary of the corresponding stratum sl k The point set P k ;

[0104] (3-4) Select the point set P k Any point p in v,k ;

[0105] (3-5) Calculate point p based on adjacent points v,k The tangent direction near the tangent direction is calculated based on the tangent direction. v,k The normal inclination angle ω at

[0106] (3-6) Based on the inclination angle ω and the formation thickness s k Calculate p according to the following formula v,k The corresponding point p in the bottom boundary of the corresponding stratum v,k+1 The coordinates (x v,k+1 ,y v,k+1 ), and store it in the point set P k+1 :

[0107]

[0108] (3-7) Repeat steps (3-4) to (3-6) until P k After traversing all the points in, we get the point set P k+1 ={p v,k+1 |v=1,2,...,PN}, and the point set P k+1 Transformed into stratigraphic boundary sl k+1 , stored in the stratigraphic boundary set SL, PN represents the number of points of the reference stratigraphic boundary;

[0109] (3-8) Determine whether k = SN. If not, k = k + 1 and return to step (3-2). Otherwise, terminate the iteration and obtain the stratum boundary set SL = {sl k |k=0,1,2,...,SN}, SN represents the number of strata.

[0110] (4) Convert the stratigraphic boundary set SL of the intermediate section into the intermediate section sc mid ,like Figure 3 shown.

[0111] (5) Based on the intermediate section sc mid The fold hinge parameter set A is processed by affine transformation to generate the cross-section set SC of the fold in the hinge direction.

[0112] This step includes:

[0113] (5-1) Obtain the hinge front-back inclination angle and hinge front-back strike of the middle section from the fold hinge parameter set A, and record them as η1, η2;

[0114] (5-2) Read the distance between the section to be generated and the middle section in the fold hinge parameter set A and store it in the set DST = {dst l |l=1,2,...,n}, where dst l represents the distance between the lth section to be generated and the middle section, and n represents the number of sections to be inserted and generated;

[0115] (5-3) Select any section distance dst l ;

[0116] (5-4) Based on η1, η2, and dst l , calculate the profile scaling coefficients scale1 and scale2 in the front and rear directions according to the following formula, and then obtain the affine transformation matrices T1 and T2;

[0117]

[0118]

[0119]

[0120] In the formula, CD mid Represents the middle section sc mid Length of the axial surface;

[0121] (5-5) According to the middle section sc mid , affine transformation matrix T1 or T2, according to the following formula for sc mid Perform matrix operations on each point in the matrix to generate the corresponding section sc l , and store it in the profile collection SC:

[0122]

[0123] Among them, x, y, and z are the middle section sc mid The three-axis coordinates of any point in the equation, x′, y′, and z′ are the three-dimensional coordinates of the corresponding point of the front or rear section respectively. T is substituted into T1 or T2 according to the position of the section to be calculated. When calculating the front section, it is substituted into T1, and when calculating the rear section, it is substituted into T2.

[0124] (5-6) Repeat steps (5-3) to (5-5) until all sections are generated, and obtain the section set SC = {sc l |l=1,2,...,n}.

[0125] (6) Based on the section set SC, a symbolic three-dimensional fold model is generated through the Morphing interpolation algorithm.

[0126] This step includes:

[0127] (6-1) According to the profile set SC, the geological boundaries of each profile are obtained, and based on the starting and ending points and the middle points of the geological boundaries of each profile, three constraint boundaries are generated by Lagrange interpolation and stored in the constraint boundary set CL for Morphing interpolation of each layer = {cl k |k=1,2,...,SN}, SN represents the number of strata, cl k represents the kth constraint boundary; Figure 4 As shown;

[0128] The above constraint boundary generation method refers to the following literature: [1] Ming Jing, Yan Mei. Three-dimensional geological interface generation based on Morphing [J]. Geography and Geographic Information Science, 2014, 30(01): 37-40. [2] Li Anbo, Wan Xia, Wang Kailiang, Lu Guonian. A three-dimensional model construction method for horizontal structural landform entities [P]. Jiangsu Province: CN110400371A, 2019-11-01.

[0129] (6-2) Take any constrained boundary line cl of a stratum k And generate the corresponding three-dimensional point set P3D through the Morphing interpolation algorithm k ;

[0130] (6-3) Using three-dimensional point set P3D k A three-dimensional model of the kth layer of folds is formed;

[0131] (6-4) Execute steps (6-2)-(6-3) repeatedly until the three-dimensional fold model of each layer is completed;

[0132] (6-5) Output the model result as a model file in obj format and bind the corresponding material, such as Figure 5 shown.

[0133] This embodiment only takes oblique folds as an example to construct a fold structure three-dimensional model. It is also possible to construct and generate three-dimensional models of different fold types according to different fold element parameters, such as Figure 6 , Figure 7 , Figure 8 As shown. In this embodiment, shp data is generated based on the feature processing interface provided by the GDAL open source code, and other libraries such as ArcEngine can also be used to generate shp data. In this embodiment, only the fold structure three-dimensional model is exported in OBJ format, and the three-dimensional geological model in other formats such as FBX can also be exported.

[0134] This embodiment also provides a device for constructing a parametric three-dimensional model of a pleated structure, including a processor and a computer program stored in a memory and executable on the processor, wherein the processor implements the above method when executing the program.

[0135] The above disclosure is only a preferred embodiment of the present invention, which cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A method for constructing a parametric three-dimensional model of a fold structure, characterized in that The method includes: (1) Obtaining the fold parameters set by the user to form a fold hinge parameter set A, a fold element parameter set F, and a stratum thickness set S; (2) Based on the fold element parameter set F, generate the reference stratigraphic boundary sl0 of the fold middle section and store it in the stratigraphic boundary set SL; (3) Based on the formation thickness set S and the reference formation boundary sl0, according to the arrangement law of the fold formation, the remaining formation boundaries of the intermediate section are generated and stored in the formation boundary set SL; (4) Convert the stratigraphic boundary set SL of the intermediate section into the intermediate section sc mid ; (5) Based on the intermediate section sc mid and the fold hinge parameter set A, through affine transformation processing, generate the cross-section set SC of the fold in the hinge direction; (6) Based on the section set SC, a symbolic three-dimensional fold model is generated through the Morphing interpolation algorithm; Wherein, step (5) specifically includes: (5-1) Obtain the hinge front-back inclination angle and hinge front-back strike of the middle section from the fold hinge parameter set A, and record them as η1, η2; (5-2) Read the distance between the section to be generated and the middle section in the fold hinge parameter set A and store it in the set DST = {dst l |l=1,2,...,n}, where dst l represents the distance between the lth section to be generated and the middle section, and n represents the number of sections to be inserted and generated; (5-3) Select any section distance dst l ; (5-4) Based on η1, η2, and dst l , calculate the profile scaling coefficients scale1 and scale2 in the front and rear directions according to the following formula, and then obtain the affine transformation matrices T1 and T2; In the formula, CD mid Represents the middle section sc mid Length of the axial surface; (5-5) According to the middle section sc mid , affine transformation matrix T1 or T2, according to the following formula for sc mid Perform matrix operations on each point in the matrix to generate the corresponding section sc l , and store it in the profile collection SC: Among them, x, y, and z are the middle section sc mid The three-axis coordinates of any point in ′ ,y ′ 、z ′ are the three-dimensional coordinates of the corresponding points of the front or rear section respectively. T is substituted into T1 or T2 according to the position of the section to be calculated. When calculating the front section, it is substituted into T1, and when calculating the rear section, it is substituted into T2. (5-6) Repeat steps (5-3) to (5-5) until all sections are generated, and obtain the section set SC = {sc l |l=1,2,...,n}.

2. The method for constructing a parameterized three-dimensional model of a fold structure according to claim 1, characterized in that: Step (1) comprises: (1-1) Read the fold hinge parameters set by the user, including the hinge front and rear inclination angle, the hinge front and rear direction, the axial front and rear inclination angle and the hinge width, and store them in the fold hinge parameter set A; (1-2) Read the fold element parameters set by the user, including the left turning point position, the right turning point position, the axial inclination angle, the wing angle and the fold shape, and store them in the fold element parameter set F; (1-3) Read the stratum thickness set by the user and store it in the stratum thickness set S = {s k |k=1,2,...,SN}, where s k It indicates the thickness of the kth stratum from top to bottom set by the user, and SN indicates the number of strata.

3. The method for constructing a parameterized three-dimensional model of a fold structure according to claim 1, characterized in that: Step (2) comprises: (2-1) Obtain the left turning point position f in the fold element parameter set F p1 and the right inflection point position f pr , generate the left turning point p1 and the right turning point p of the fold element r , and store the reference stratigraphic boundary point set P0 of the middle section of the fold; (2-2) Read the axial inclination angle, inter-wing angle and fold morphological parameters of the fold element in the fold element parameter set F, and record them as γ, δ and curve respectively; (2-3) Calculate the inclination angles α and β of the left and right turning ends according to the following formula: (2-4) According to the inflection point p l and p r , and the inclination angles α and β, the vertex on the axial surface of the fold element is obtained by the point-slope intersection method, which is recorded as vertex C; (2-5) According to the axial inclination angle γ and the vertex C, calculate the axis and the bottom line p of the fold element l p r The intersection point D is taken as the vertex D under the axial plane; (2-6) Axial plane CD is generated based on vertex C and vertex D, and the turning point E of the wrinkle element is obtained on the axial plane CD. The turning point makes the following equation true: (2-7) Draw FG⊥CD through point E, intersecting p l C.p r C is at Bezier control points F and G; (2-8) are based on point p l , F, E and points E, G, p r , generate two continuous Bezier curve point sets and store them in the reference stratigraphic boundary point set P0; (2-9) Based on the maximum rotation angle amax and rotation radius R set by the user, the reference stratum boundary point set P0 is distorted and deformed to obtain the deformed point set P0 ′ So that it can be closer to the actual stratigraphic distribution when depicting the inverted strata; (2-10) The deformation point set P0 ′ Convert it into the corresponding reference stratigraphic boundary sl0 and store it in the stratigraphic boundary set SL.

4. The method for constructing a parameterized three-dimensional model of a fold structure according to claim 3, characterized in that: Steps (2-9) include: (2-9-1) Select any point p from the reference stratigraphic boundary point set P0 m,0 ; (2-9-2) Calculate p m,0 The distance from point D is denoted as r; (2-9-3) Calculate point p according to the following formula m,0 The rotation angle θ at: θ=amax×(Rr) / R (2-9-4) point p m,0 Rotate θ to get the distorted point p′ m,0 , and store it in the deformation point set P0 ′ ; (2-9-5) Loop through steps (2-9-1) to (2-9-4) until all points in P0 are deformed, and the deformed point set P0 is obtained. ′ = {p′ m,0 |m=1,2,...,PN}, PN represents the number of points of the reference stratigraphic boundary.

5. The method for constructing a parameterized three-dimensional model of a fold structure according to claim 1, characterized in that: Step (3) includes: (3-1) Set k = 0, where 0 is the serial number of the reference stratigraphic boundary sl0; (3-2) Select the formation thickness s from the formation thickness set S k ; (3-3) Obtaining the formation thickness s k The stratigraphic boundary of the corresponding stratum sl k The point set P k ; (3-4) Select the point set P k Any point p in v,k ; (3-5) Calculate point p based on adjacent points v,k The tangent direction near the tangent direction is calculated based on the tangent direction. v,k The normal inclination angle ω at (3-6) Based on the inclination angle ω and the formation thickness s k Calculate p according to the following formula v,k The corresponding point p in the bottom boundary of the corresponding stratum v,k+1 The coordinates (x v,k+1 ,y v,k+1 ), and store it in the point set P k+1 : (3-7) Repeat steps (3-4) to (3-6) until P k After traversing all the points in, we get the point set P k+1 ={p v,k+1 |v=1,2,...,PN}, and the point set P k+1 Transformed into stratigraphic boundary sl k+1 , stored in the stratigraphic boundary set SL, PN represents the number of points of the reference stratigraphic boundary; (3-8) Determine whether k = SN. If not, k = k + 1 and return to step (3-2). Otherwise, terminate the iteration and obtain the stratum boundary set SL = {sl k |k=0,1,2,...,SN}, SN represents the number of strata.

6. The method for constructing a parameterized three-dimensional model of a fold structure according to claim 1, characterized in that: Step (6) comprises: (6-1) According to the profile set SC, the geological boundaries of each profile are obtained, and based on the starting and ending points and the middle points of the geological boundaries of each profile, three constraint boundaries are generated by Lagrange interpolation and stored in the constraint boundary set CL for Morphing interpolation of each layer = {cl k |k=1,2,...,SN}, SN represents the number of strata, cl k represents the kth constraint boundary; (6-2) Take any constrained boundary line cl of a stratum k And generate the corresponding three-dimensional point set P3D through the Morphing interpolation algorithm k ; (6-3) Using three-dimensional point set P3D k A three-dimensional model of the kth layer of folds is formed; (6-4) Execute steps (6-2)-(6-3) repeatedly until the three-dimensional fold model of each layer is completed; (6-5) Output the model results as a model file in obj format and bind the corresponding material.

7. A device for constructing a parametric three-dimensional model of a fold structure, comprising a processor and a computer program stored in a memory and executable on the processor, characterized in that: When the processor executes the program, the method according to any one of claims 1 to 6 is implemented.

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