CN113066180B

CN113066180B - Vault structure three-dimensional modeling method based on geological map

Info

Publication number: CN113066180B
Application number: CN202110366178.8A
Authority: CN
Inventors: 刘先裕; 李安波; 沈言根; 陈浩; 毛一鹏
Original assignee: Nanjing Normal University
Current assignee: Nanjing Normal University
Priority date: 2021-04-06
Filing date: 2021-04-06
Publication date: 2024-06-21
Anticipated expiration: 2041-04-06
Also published as: CN113066180A

Abstract

The invention discloses a vault structure three-dimensional modeling method based on a geological map, which comprises the steps of firstly, reading a planar stratum layer, ground surface DEM data and known occurrence point data; secondly, calculating the occurrence of each stratum boundary; then, constructing a three-dimensional model of the top surface, the side surface and the bottom surface of the stratum based on the ground surface data and the stratum boundary line occurrence; and finally, stitching the stratum three-dimensional model, binding materials, and exporting a model file. The vault structure three-dimensional model construction method based on the geological map has the advantages of less dependence on modeling data and higher automation degree and modeling precision.

Description

Vault structure three-dimensional modeling method based on geological map

Technical Field

The invention belongs to the technical field of three-dimensional geologic modeling, and particularly relates to a vault structure three-dimensional modeling method based on geologic maps.

Background

The three-dimensional geological modeling has very important research significance and application value in various fields such as urban planning, engineering construction, oil gas storage, digital mines and the like. The vault structure is used as an advantageous oil storage structure and an important travel resource, and the three-dimensional modeling method for researching the vault structure has the same important research significance and application value.

The dome structure is a special form of anticline structure developed on the floor covering layer, and its form is approximately circular, and its middle portion is in the form of dome. The vault architecture that develops in the bedrock region is often where borehole and geologic profile data is missing or sparse. Traditional geological modeling techniques based on geological survey data such as drilling holes, geological sections and the like are difficult to apply. Compared with the drilling and profile data, the geological map has low acquisition difficulty and wide coverage range, and can provide geological structure information and stratum information required by bedrock area modeling under the condition of lacking other geological data.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a vault structure three-dimensional modeling method based on a geological map, which not only avoids excessive dependence on geological survey data such as drilling, profile and the like, but also has higher automation degree and modeling precision.

In order to solve the technical problems, the invention provides a vault structure three-dimensional modeling method based on a geological map, which comprises the following steps:

(1) Loading stratum layers, DEM and production point data;

(2) Reading a planar stratum element s _i from outside to inside, and calculating the occurrence of each point in the outer boundary of the stratum;

(3) Constructing the outer side surface of the stratum according to the attitude information of the stratum and the altitude H of the modeling bottom surface appointed by the user;

(4) Circularly executing the steps (2) to (3) until the generation of the outer side surfaces of all stratum is completed;

(5) Generating the formation top model TFace for a formation element s _i based on the top edges of the inner and outer sides of the formation and DEM sampling points;

(6) Generating the formation floor model BFace for a formation element s _i based on the bottom edges of the inner and outer sides of the formation;

(7) Stitching the top surface, the inner side surface, the outer side surface and the bottom surface of the stratum to obtain a geologic body model of the current stratum;

(8) And (3) circularly executing the steps (5) to (7) to obtain three-dimensional models of all stratum, storing the three-dimensional models into a model set, and binding materials to generate the three-dimensional model of the fornix structure.

Preferably, in the step (1), loading the stratum layer, the DEM and the occurrence point data specifically includes the following steps:

(1-1) reading a stratum layer, and saving stratum elements into a set s= { S _i |i=1, 2,.. SN } where i represents a stratum number and SN represents the number of stratum;

(1-2) reading DEM data, extracting a pixel center point, obtaining a pixel value at the point as an elevation value, and storing a sampling point set ip= { IP _k |k=1, 2, &..in }, wherein k represents a sampling point number and IN represents the number of sampling points;

(1-3) reading the occurrence point data, storing the occurrence point data in an occurrence point set kp= { KP _l |l=1, 2.

Preferably, in the step (2), a planar stratum element s _i is read from outside to inside, and calculating the occurrence of each point in the outer boundary of the stratum specifically includes the following steps:

(2-1) reading a stratum element s _i, sequentially obtaining all boundary points of the outer boundary of the stratum element s _i, extracting elevation values of pixels corresponding to each point from the DEM, and storing the elevation values into a three-dimensional point set OP= { OP _j(x_j,y_j,z_j) |j=1, 2..n }, wherein j represents a serial number of the boundary point, x _j,y_j,z_j is a transverse coordinate, a longitudinal coordinate and an elevation value of the boundary point respectively, and n represents the number of the boundary point;

(2-2) assigning inclination information of each occurrence point to a boundary point nearest thereto based on the occurrence point number c and the labeling position of the current formation;

(2-3) dividing the point set OP into c packets with boundary points having inclination values as end points of the packets;

(2-4) calculating the inclination angle of any point in the group by linear interpolation according to the inclination angles of the two boundary end points in each group;

(2-5) calculating a tendency at any boundary point OP _j in the set of points OP;

(2-6) looping step (2-5), calculating formation dip information AT all boundary points, and storing the formation dip information in a zone set at= { α _j (ρ, θ) |j=1, 2,...

Preferably, in the step (2-5), the calculating the tendency at any boundary point OP _j in the point set OP specifically includes the following steps:

(2-5-1) substituting coordinates of the boundary point op _j and two adjacent boundary points thereof into the formula (1) to obtain coefficients A, B and C of a local stratum layer equation (shown in the formula (2), wherein D is an arbitrary constant), wherein { A, B, C } is a normal line of a triangular surface determined by three boundary points;

Ax+By+Cz+D＝0 (2)

(2-5-2) determining a formation dip line equation (shown in formula (3)) based on the coefficients A, B, wherein M is any real number;

Bx+Ay+M＝0 (3)

(2-5-3) the tendency ρ is corrected by the formulas (4) and (5), respectively.

Preferably, in the step (3), constructing the formation outer side mask specifically includes the following steps according to the formation attitude information and the altitude H of the modeling bottom specified by the user:

(3-1) calculating a stratum bottom surface boundary point DP _j(x′_j,y′_j,z′_j corresponding to any stratum boundary point op _j according to the attitude information of the point and the altitude H of the modeling bottom surface appointed by a user and according to a formula (6), and storing the stratum bottom surface boundary point DP;

(3-2) checking and eliminating the self-intersection condition of the bottom edges with respect to the set DP, and generating an optimized bottom edge set DP'.

(3-3) Determining two triangular surfaces based on OP _j、dp_j、op_j+1 and OP _j+1、dp_j、dp_j+1 in sequence according to the top set OP and the bottom set DP', and storing the two triangular surfaces in the outer triangular surface set OutSide of the earth.

Preferably, in the step (3-2), for the set DP, the self-intersecting condition of the bottom edge is checked and eliminated, and the generating the optimized bottom edge set DP' specifically includes the following steps:

(3-2-1) taking any two adjacent bottom boundary points DP _j and DP _j+1 in the set DP, checking the boundary line segments backwards along the boundary, and finding the last boundary line segment intersecting the projection of the boundary formed by the current two points on the xOy plane;

(3-2-2) marking the self-intersecting point as isp _j(x″′_j,y″′_j,z″′_j) and being located before dp _j+num+1, wherein the value of Z' "_j is the average of the values of dp _j and dp _j+num+1 Z, and num is the number of points between dp _j and dp _j+num+1;

(3-2-3) num boundary points located between dp _j and dp _j+num+1 are uniformly moved onto two line segments defined by points dp _j、isp_j and dp _j+num+1.

Preferably, in step (5), for a formation element s _i, generating the formation top model TFace based on the top edges of the inner and outer sides of the formation and DEM sampling points specifically includes the following steps:

(5-1) extracting inner and outer boundary points of the current stratum element s _i based on the element;

(5-2) extracting internal sampling points of the formation based on the current formation element s _i and the set of sampling points IP;

(5-3) generating a top surface model TFace of the formation s _i based on the inner and outer boundary points and the inner sampling points of the current element.

Preferably, in the step (6), for a formation element s _i, generating the formation bottom surface model BFace based on the bottom edges of the inner and outer sides of the formation specifically includes the following steps:

(6-1) extracting inner and outer boundary points of the current formation element s _i based on the element;

(6-2) generating a floor model BFace of the formation s _i based on the inner and outer boundary points of the current element.

Preferably, in the step (7), the top surface, the inner side surface, the outer side surface and the bottom surface of the stratum are stitched, and the geologic body model of the current stratum is obtained specifically includes the following steps:

(7-1) merging the outside triangular face set OutSide and the inside triangular face set InSide of the stratum s _i, and storing into a triangular face set Side;

(7-2) based on the same boundary vertices, the inside and outside Side of the formation s _i, the bottom model BFace, and the top model TFace are combined and output as a three-dimensional model of the current formation.

The beneficial effects of the invention are as follows: the invention not only avoids the excessive dependence on geological survey data such as drilling, profile and the like, but also has higher automation degree and modeling precision.

Drawings

Fig. 1 is a graph of surface DEM data employed in the present invention.

FIG. 2 is a plot of formation data used in the present invention.

FIG. 3 is a schematic flow chart of the method of the present invention.

FIG. 4 is a schematic diagram of the present invention for inspecting the self-intersection of the bottom boundary.

FIG. 5 is a schematic diagram of the present invention for eliminating bottom boundary self-intersection.

Fig. 6 (a) is a schematic diagram of a three-dimensional model of the hillside group of the lingyan mountain constructed by the invention.

Fig. 6 (b) is a schematic diagram of a three-dimensional model of the Lingshan Yuhua table set constructed in the invention.

Fig. 6 (c) is a schematic diagram of a three-dimensional model of a smart rock mountain square mountain group constructed by the invention.

FIG. 7 is a schematic illustration of a rock-like mountain vault model constructed in accordance with the present invention.

Detailed Description

As shown in fig. 1 and 2, in this embodiment, the surface DEM data and the stratum layer of the ling mountain of the south kyo city are selected as experimental data, and the projection coordinate system adopted by the experimental data is the local coordinate system of the south kyo 92. Further description will be provided by describing a specific embodiment with reference to the accompanying drawings.

As shown in fig. 3, the embodiment provides a three-dimensional modeling method for a fornix structural unit based on a geological map, which specifically includes the following steps:

(1) Loading stratum layers, DEM and production point data; the method specifically comprises the following steps:

(1-1) reading the stratum layers, and saving stratum elements into a set s= { S _i |i=1, 2,..sn } where i represents a stratum number and SN represents the number of stratum. In the embodiment, the SN is 3, and the stratum is an red mountain group, a Yuhua table group and a Fangshan group from outside to inside;

(1-2) reading DEM data, extracting a pixel center point, obtaining a pixel value at the point as an elevation value, and storing a set of sampling points ip= { IP _k |k=1, 2. IN this embodiment, IN is 2538;

(1-3) reading the occurrence point data, storing the occurrence point data in an occurrence point set kp= { KP _l |l=1, 2. In this example, c is 5 and the original yield information is as shown in Table 1;

table 1 raw birth information table

Calm point ID	Stratum where it is	Trend (°)	Trend (°)	Inclination angle (°)
					1	Chishan group	226	316	32
2	Chishan group	32	122	36
					3	Rain flower table set	7	97	45
4	Square mountain group	1	91	50
					5	Square mountain group	120	210	52

(2) Reading a planar stratum element p _i from outside to inside, and calculating the occurrence of each point in the outer boundary of the stratum; the method specifically comprises the following steps:

(2-1) reading a stratum element s _i, sequentially obtaining all boundary points of the outer boundary of the stratum element s _i, extracting elevation values of pixels corresponding to each point from the DEM, and storing the elevation values into a three-dimensional point set OP= { OP _j(x_j,y_j,z_j) |j=1, 2. In this embodiment, n is 140 for the red mountain group; for a rain flower table group, n is 104; for the Fangshan group, n is 98;

Further, the step (2-5) includes:

Ax+By+Cz+D＝0 (2)

Bx+Ay+M＝0 (3)

(2-5-3) calculating and correcting the tendency ρ from the formulas (4) and (5), respectively;

(2-6) looping step (2-5), calculating formation dip information AT all boundary points, and storing the formation dip information in a zone set at= { α _j (ρ, θ) |j=1, 2,... Table 2 shows the occurrence information of part of the boundary points;

Table 2 boundary point yield information table

(3) Constructing the outer side surface of the stratum according to the attitude information of the stratum and the altitude H of the modeling bottom surface appointed by the user; the method specifically comprises the following steps:

(3-2) checking and eliminating the self-intersection condition of the bottom edges for the set DP as shown in fig. 4 and 5, generating an optimized bottom edge set DP';

further, the step (3-2) includes:

(3-2-3) uniformly moving num boundary points located between dp _j and dp _j+num+1 onto two line segments defined by points dp _j、isp_j and dp _j+num+1;

(3-3) determining two triangular surfaces based on OP _j、dp_j、op_j+1 and OP _j+1、dp_j、dp_j+1 in sequence according to the top edge set OP and the bottom edge set DP', and storing the two triangular surfaces in the triangular surface set OutSide on the outer side of the ground;

(5) Generating the formation top model TFace for a formation element s _i based on the top edges of the inner and outer sides of the formation and DEM sampling points; the method specifically comprises the following steps:

(5-3) generating a top surface model TFace of the formation s _i based on the inner and outer boundary points and the inner sampling points of the current element;

(6) Generating the formation floor model BFace for a formation p _i based on the bottom edges of the inner and outer sides of the formation; the method specifically comprises the following steps:

(6-2) generating a floor model BFace of the formation s _i based on the inner and outer boundary points of the current element;

(7) Stitching the top surface, the inner side surface, the outer side surface and the bottom surface of the stratum to obtain a geologic body model of the current stratum; the method specifically comprises the following steps:

(7-2) merging the inside and outside Side of the formation s _i, the bottom model BFace, and the top model TFace based on the same boundary vertices, and outputting as a three-dimensional model of the current formation;

(8) And (3) circularly executing the steps (5) to (7), as shown in fig. 6 (a) - (c), obtaining a three-dimensional model of each stratum, storing the model set, binding materials, and as shown in fig. 7, generating the three-dimensional model of the fornix structure.

In this embodiment, DEM data is read only based on an image processing interface provided by GDAL open source codes, and the method may also use interfaces of GIS software such as SuperMap, QGIS. In this embodiment, the three-dimensional stratum model is derived only in OBJ format, and the method may also be used to derive three-dimensional stratum models in other formats such as FBX.

Claims

1. The vault structure three-dimensional modeling method based on the geological map is characterized by comprising the following steps of:

(1) Loading stratum layers, DEM and production point data;

2. The method of three-dimensional modeling of geologic map based fornix structures of claim 1, wherein in step (1), loading the stratigraphic layers, DEM and yield point data comprises the steps of:

3. The method of three-dimensional modeling of a geologic map based fornix structure of claim 1, wherein in step (2), reading a planar formation element s _i from outside to inside, and calculating the occurrence of each point in the outer boundary of the formation comprises the steps of:

4. The method of three-dimensional modeling of a geologic map based fornix structure of claim 3, wherein in step (2-5), calculating trends at any boundary point OP _j in the set of points OP specifically comprises the steps of:

(2-5-1) substituting coordinates of the boundary point op _j and two adjacent boundary points thereof into the formula (1) to obtain coefficients A, B and C of the local stratum layer equation, wherein { A, B, C } is a normal line of a triangular surface determined by three boundary points, and D is an arbitrary constant;

Ax+By+Cz+D＝0 (2)

(2-5-2) determining a formation dip line equation based on the coefficients A, B, wherein M is any real number;

Bx+Ay+M＝0 (3)

(2-5-3) calculating and correcting the tendency ρ from the formulas (4) and (5), respectively,

5. The method of three-dimensional modeling of a geologic map based fornix structure of claim 1, wherein in step (3), constructing an outer side of the formation based on the formation's attitude information and the elevation H of the user-specified modeled floor surface comprises the steps of:

(3-2) checking and eliminating self-intersection conditions of the bottom edges aiming at the set DP, and generating an optimized bottom edge set DP';

6. The method of three-dimensional modeling of a geologic map based fornix structure of claim 5, wherein in step (3-2), for the set DP, the step of examining and eliminating the self-intersection of the bottom edges, generating an optimized bottom edge set DP' comprises the steps of:

7. The method of claim 1, wherein in step (5), generating the formation top model TFace based on the top edges of the inner and outer sides of the formation and DEM sampling points for a formation element s _i comprises:

8. The method of claim 1, wherein in step (6), generating the formation floor model BFace based on the bottom edges of the inner and outer sides of a formation for a formation element s _i comprises:

9. The method of three-dimensional modeling of a dome structure based on geologic map of claim 1, wherein in step (7), stitching the top, inner and outer sides and bottom of the formation to obtain a geologic body model of the current formation comprises the steps of: