A method and system for constructing a three-dimensional geological unconformity surface

Abstract

This invention provides a method and system for constructing three-dimensional geological unconformities. The method and system use geological map vector data and borehole logging data as the raw data for constructing the unconformity surface. The data is identified and unconformity lines and points are extracted. These unconformity lines and points are classified according to the same property. After classification, unconformity lines and points of the same property are merged to form a three-dimensional point set. One type of three-dimensional point set is used as constraint data to triangulate the entire model construction area, forming a triangular mesh surface. The surface spatial morphology is then corrected, and the corrected surface is the unconformity surface. This process is repeated, using all three-dimensional point sets as constraint data to construct unconformity surfaces, and each unconformity surface is output separately. This method and system improve the accuracy of three-dimensional model simulation of deep unconformities, assisting professionals in more accurately understanding deep geological structures.

Description

Technical Field

[0001] This invention relates to the field of geological three-dimensional modeling technology, and in particular to a method and system for constructing three-dimensional geological unconformities. Background Technology

[0002] An unconformity is a discontinuity between strata, formed by factors such as faulting, erosion, or sedimentary interruptions during geological processes. In geology, an unconformity typically indicates a discontinuity in strata, meaning that the overlying strata are not directly deposited on the surface of the underlying strata, but rather one or more layers develop on the surface of the underlying strata. In geological exploration and engineering geology, identifying and studying unconformities is crucial for understanding geological history, predicting stratigraphic distribution, and assessing geological hazard risks. Therefore, accurate identification, description, and modeling of unconformities are of significant value for geological research and engineering applications.

[0003] In the field of geological 3D modeling technology, the usual approach is to extend the stratigraphic planes according to their dip and dip angle based on surface measurement data, and infer unconformities based on the pinch-out relationships between stratigraphic layers. However, this construction method relies solely on surface measurement data for inference, without any other data to constrain the deep structure. Consequently, the inferred unconformities cannot accurately reflect the distribution of deep structures. Summary of the Invention

[0004] The purpose of this invention is to provide a method and system for constructing a three-dimensional geological unconformity surface. This method integrates the surface unconformity boundary with unconformity points reflected in deep borehole data to create a model, inferring the extension direction of the unconformity surface at depth. The constructed three-dimensional unconformity surface incorporates constraints from deep data, thus addressing the problem of low accuracy in deep simulation of unconformity structures. The specific technical solution is as follows:

[0005] A method for constructing a three-dimensional geological unconformity, the method specifically includes the following steps:

[0006] S1. Input the initial data for constructing the unconformable surface;

[0007] S2. Identify unintegrated structures based on the data in step S1;

[0008] S3. Extract unconformity construction lines and unconformity construction points;

[0009] S4. Classify the extracted unconformity construction lines and unconformity construction points;

[0010] S5. Merge the data of unconformity construction lines and unconformity construction points of the same category;

[0011] S6. Using the fused data of the same category as constraint data, construct a three-dimensional non-conformity surface;

[0012] S7. Construct all unconformity surfaces in sequence according to steps S5 and S6, and output them separately.

[0013] Furthermore, the initial data mentioned in step S1 includes geological map vector data and borehole logging data.

[0014] Furthermore, step S2 specifically includes:

[0015] S21. Identification of unconformity tectonic boundaries based on geological map vector data;

[0016] S22. Identify the location of unconformity structural surfaces based on borehole logging data.

[0017] Furthermore, step S3 specifically includes:

[0018] S31. Extract the identified unconformity boundaries as unconformity lines;

[0019] S32. Extract the exposed locations of the identified unconformity surfaces as unconformity points.

[0020] Furthermore, the classification criterion described in step S4 is to determine unconformities of the same nature.

[0021] Furthermore, the data fusion in step S5 involves converting the unconformity construction line into three-dimensional points and merging it with the unconformity construction points to form a set of three-dimensional points of the same category.

[0022] Furthermore, step S6 specifically includes:

[0023] S61. Within the model construction area, using the same set of 3D points of the same category as constraint data, the entire area is triangulated to form a triangular mesh surface.

[0024] S62. By using spatial interpolation, a new Z-value coordinate of the set of vertices of the triangular mesh is generated, and the spatial morphology correction of the triangular mesh surface is completed. The corrected surface is the unconformity construction surface.

[0025] Furthermore, the unintegrated construction surface described in step S7 can be output in off format.

[0026] The present invention also provides a system for constructing a three-dimensional geological unconformity. The system is based on the above-described method for constructing a three-dimensional geological unconformity. The system includes a data input module, a data extraction module connected to the output end of the data input module, a data classification module connected to the output end of the data extraction module, a data fusion module connected to the output end of the data classification module, a surface construction module connected to the output end of the data fusion module, and a surface output module connected to the output end of the surface construction module.

[0027] The data input module is used to input geological map vector data and borehole stratigraphic logging data.

[0028] The data extraction module is used to identify unconformity boundaries and unconformity surfaces, and to extract unconformity lines and unconformity points.

[0029] The data classification module is used to classify the extracted unconformity construction lines and unconformity construction points according to the same property.

[0030] The data fusion module is used to fuse unconformity construction lines and unconformity construction points of the same category to form three-dimensional point sets of different categories.

[0031] The surface construction module is used to construct a triangular mesh surface by triangulating a defined area based on a three-dimensional point set as input data, and to complete the surface spatial morphology correction. The corrected surface is the unconformity surface.

[0032] The surface output module is used to output the constructed unconformity surface.

[0033] Furthermore, the geological map vector data is input in shp or mapgis format, and the borehole logging data is input in Excel spreadsheet format.

[0034] The present invention provides a method and system for constructing a three-dimensional geological unconformity, which has the following beneficial effects:

[0035] This invention proposes a method and system for constructing three-dimensional geological unconformities. Based on geological map vector data and borehole logging data, it integrates surface geological measurement data and deep geological drilling data into the three-dimensional modeling process. This solves the problem of the lack of deep data constraints in traditional inference methods, improves the accuracy of three-dimensional model simulation of deep unconformities, and assists professionals in more accurately understanding deep geological structures. Attached Figure Description

[0036] Figure 1 This is a flowchart illustrating a method for constructing a three-dimensional geological unconformity provided by the present invention;

[0037] Figure 2 This is a schematic diagram of an identification method for nonconformity construction boundaries in Embodiment 1 of the present invention;

[0038] Figure 3 This is a schematic diagram illustrating the identification method for the exposed location of the unconformable structural surface in Embodiment 1 of the present invention;

[0039] Figure 4 This is a borehole logging layered data map used to extract unconformity construction points in Embodiment 1 of the present invention;

[0040] Figure 5 This is a schematic diagram of one type of unconformable surface constructed in Embodiment 1 of the present invention;

[0041] Figure 6 This is a schematic diagram of the structure of a system for constructing a three-dimensional geological unconformity provided by the present invention. Detailed Implementation

[0042] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The advantages and features of the present invention will become clearer from the following description. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clearly illustrate the purpose of the embodiments of the present invention.

[0043] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connection" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two elements or the interaction between two elements. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0044] In the description of this invention, terms such as "upper," "lower," "left," "right," "front," "back," "center," "horizontal," "vertical," "top," "bottom," "inner," and "outer," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0045] Example 1: See Figure 1 As shown in the figure, this embodiment provides a method for constructing a three-dimensional geological unconformity, which specifically includes the following steps:

[0046] S1. Input the initial data for constructing the unconformable surface;

[0047] Specifically, geological map vector data and borehole logging data are input as the raw data for constructing the unconformity structural surface. The geological map vector data is mainly in shp or mapgis format, and the borehole logging data is in Excel report format, which includes borehole coordinate information and stratigraphic logging information.

[0048] S2. Identify unintegrated structures based on the data in step S1;

[0049] S21. Identification of unconformity tectonic boundaries based on geological map vector data;

[0050] Specifically, there are two methods to identify unconformity boundaries. The first method is that unconformities are represented as line data on geological maps, usually possessing specific attribute information. These attributes indicate which stratum a particular boundary represents, such as a fault line or angular unconformity. By iterating through all geological boundaries on the map, unconformity boundaries can be identified through these attribute information. The second method is that if boundary attributes are not specified, unconformity boundaries can be identified based on the spatial relationships of vector elements. For example, if the surface stratigraphic attributes on both sides of the boundary are consistent but spatially misaligned, or if the surface stratigraphic attributes on both sides of the boundary are not arranged according to the standard stratigraphic sequence (i.e., missing strata), then the boundary is considered an unconformity boundary. (See also...) Figure 2 As shown, the two line segments F1 and F2 divide the continuous spatial surface into different parts, causing the surfaces on both sides to be misaligned, which has the typical characteristics of unconformity. By identifying this feature, the distribution of unconformity boundaries on the geological map can be determined. The two line segments F1 and F2 are the unconformity boundaries.

[0051] S22. Identify the location of unconformity structural surfaces based on borehole logging data.

[0052] Specifically, strata are typically continuous in areas without unconformities, while they are discontinuous and incomplete in areas with unconformities. This is used to identify the location of unconformities in a specific borehole logging data. See also... Figure 3 As shown in Figure a, if all strata 1-10 appear sequentially in the borehole logging data, it is generally considered that there are no unconformity structural surfaces in the borehole. (See also...) Figure 3 As shown in b, if stratum 2 is missing, it is assumed that the unconformity surface in the borehole is exposed between stratum 1 and stratum 3, that is, the location of the unconformity surface exposure is at the position of the black line segment in the figure.

[0053] S3. Extract unconformity construction lines and unconformity construction points;

[0054] S31. Extract the identified unconformity boundaries as unconformity lines;

[0055] Specifically, extracting unconformity structural lines involves extracting the unconformity structural boundaries identified on the geological map, projecting the unconformity structural boundaries onto the DEM data (the DEM data records the elevation information of all points within the working area), calculating the elevation information of each inflection point of the unconformity structural boundary, that is, assigning the Z coordinate to each inflection point of the unconformity structural boundary, and forming a three-dimensional polyline.

[0056] S32. Extract the exposed locations of the identified unconformity surfaces as unconformity points.

[0057] Specifically, extracting unconformity points involves identifying the locations of unconformity surfaces in borehole logging data and converting them into spatial points. This is done by extracting the top elevation data of the upper and lower strata of missing formations from the logging data, along with the borehole coordinates, to create three-dimensional spatial points. (See also...) Figure 4 The image shows the stratification data of a borehole. Assuming the borehole coordinates are (X,Y), according to the standard stratigraphic sequence, the borehole is missing the second layer, which is located between layers 1 and 3. That is, the unconformity point is located between layers 1 and 3. Therefore, the top elevation of layer 3 is taken as the Z coordinate of the unconformity point. The final extracted three-dimensional coordinates of the unconformity point are (X,Y,90).

[0058] S4. Classify the extracted unconformity construction lines and unconformity construction points;

[0059] Specifically, the classification criteria for unconformity lines and unconformity points are based on determining whether they are unconformities of the same nature. The classification method for unconformity lines is as follows: If the attribute information of the unconformity boundary is marked in the attribute description, those with the same attribute are classified into one category. If the boundary attribute is not marked, the classification is based on spatial relationships, specifically whether the strata on both sides of the unconformity boundary are consistent. For example, if the strata on both sides of unconformity boundary A are 1 and 3, the strata on both sides of unconformity boundary B are 4 and 6, and the strata on both sides of unconformity boundary C are 1 and 3, then unconformity boundaries A and C have the same attribute and can be classified into one category. A similar scheme is used to classify unconformity points. Assuming the extracted borehole unconformity points are the missing unconformity surfaces of strata 2 and 4, these points are classified into two categories, and so on, classifying all unconformity lines and unconformity points.

[0060] S5. Merge the data of unconformity construction lines and unconformity construction points of the same category;

[0061] Specifically, since the extracted unconformity construction lines are 3D line structures and the unconformity construction points are 3D point structures, it is necessary to merge these two data structures into a single structure for modeling. Because 3D lines are also composed of 3D point structures, all unconformity construction lines are transformed into 3D points in space, i.e., the inflection points of the 3D lines are extracted, each inflection point being a 3D point. These are then merged with the unconformity construction points to form a set of 3D points. It is important to note that unconformity construction lines and points of the same category must be merged, resulting in sets of 3D points of different categories.

[0062] S6. Using the fused data of the same category as constraint data, construct a three-dimensional non-conformity surface;

[0063] Based on the model-constructed region, 3D points of the same category are used as constraint data to triangulate the entire region, forming a triangular mesh surface. This surface is composed of multiple connected triangles, its basic structure being a set of points in space. By controlling the Z-coordinates of these spatial points, the shape of the entire surface can be controlled. Here, the set of unconformity point coordinates is used as input data, and the set of triangular mesh surface vertices is used as output data. Through spatial interpolation, new Z-coordinates for the triangular mesh vertex set are generated, completing the spatial shape correction of the surface. The corrected surface is the unconformity construction surface. (See [reference needed]). Figure 5 As shown.

[0064] S7. Construct all unconformity surfaces in sequence according to steps S5 and S6, and output them separately.

[0065] Specifically, for all categories of unconformity point sets, unconformity construction surfaces are constructed separately according to steps S5 and S6, and output separately in OFF format. The OFF file format is not limited to any specific software or application; it is highly versatile and can exchange geometric data between various 3D modeling and visualization tools.

[0066] Example 2: See Figure 6 As shown, the present invention also provides a system for constructing a three-dimensional geological unconformity. The system includes a data input module, a data extraction module connected to the output end of the data input module, a data classification module connected to the output end of the data extraction module, a data fusion module connected to the output end of the data classification module, a surface construction module connected to the output end of the data fusion module, and a surface output module connected to the output end of the surface construction module.

[0067] The data input module is used to input geological map vector data and borehole stratigraphic logging data. Geological map vector data is input in shp or mapgis format, and borehole logging data is input in Excel spreadsheet format.

[0068] The data extraction module is mainly used to identify unconformity boundaries from geological material maps, identify unconformity surfaces from borehole logging data, extract unconformity boundaries as unconformity lines through elevation projection, and extract the outcrop locations of unconformity surfaces as unconformity points.

[0069] The data classification module classifies all unconformity construction lines and all unconformity construction points according to the same property.

[0070] The data fusion module merges unconformity construction lines and unconformity construction points of the same category to form three-dimensional point sets of different categories.

[0071] The surface construction module triangulates the defined area to construct a triangular mesh surface, and uses a set of three-dimensional points of the same category as input data to spatially interpolate and correct the surface shape.

[0072] The surface output module outputs the constructed surface in OFF format, enabling the exchange of geometric data between various 3D modeling and visualization tools.

[0073] Those skilled in the art should understand that the present invention can be implemented in many other specific forms without departing from the spirit and scope of the invention. Any changes or modifications made by those skilled in the art based on the embodiments of the present invention and the above disclosure shall fall within the protection scope of the claims.

Claims

1. A method of constructing a three-dimensional geological unconformity surface, characterized by: The method specifically includes the following steps: S1. Input the initial data for constructing the unconformable surface; S2. Identify unintegrated structures based on the data in step S1; S3. Extract unconformity construction lines and unconformity construction points; S4. Classify the extracted unconformity construction lines and unconformity construction points; S5. Merge the data of unconformity construction lines and unconformity construction points of the same category; S6. Using the fused data of the same category as constraint data, construct a three-dimensional non-conformity surface; S7. Construct all unconformity surfaces in sequence according to steps S5 and S6, and output them separately; The initial data mentioned in step S1 includes geological map vector data and borehole logging data; Specifically, step S2 includes: S21. Identification of unconformity tectonic boundaries based on geological map vector data; S22. Identify the location of unconformity structural surfaces based on borehole logging data; Specifically, step S3 includes: S31. Extract the identified unconformity boundaries into unconformity lines; specifically, extracting unconformity lines involves extracting the unconformity boundaries identified in the geological map, projecting the unconformity boundaries onto the DEM data, obtaining the elevation information of each unconformity boundary inflection point, that is, assigning the Z coordinate to each unconformity boundary inflection point to form a three-dimensional polyline. S32. Extract the exposed locations of the identified unconformity surfaces as unconformity points; specifically, extracting unconformity points involves extracting the exposed locations of the unconformity surfaces identified in the borehole logging data as spatial points. The extraction method is to extract the top elevation data of the upper and lower layers of the missing strata in the logging data, as well as the coordinates of the borehole points, to form three-dimensional spatial points. The classification criteria in step S4 are to determine unconformities of the same nature; specifically, if the strata on both sides of the unconformity boundary are the same, then the properties of the unconformity structure line are consistent; if the stratigraphic unconformity surfaces missing from the unconformity structure points are the same, then the properties of the unconformity structure points are consistent. In step S5, the data fusion involves converting the unconformity construction line into three-dimensional points and merging it with the unconformity construction points to form a set of three-dimensional points of the same category. Specifically, step S6 includes: S61. Within the model construction area, using the same set of 3D points of the same category as constraint data, the entire area is triangulated to form a triangular mesh surface. S62. By using spatial interpolation, a new Z-value coordinate of the set of vertices of the triangular mesh is generated, and the spatial morphology correction of the triangular mesh surface is completed. The corrected surface is the unconformity construction surface.

2. The method for constructing a three-dimensional geological unconformity according to claim 1, characterized in that: The unconformity surface described in step S7 can be output as an off format.

3. A system for constructing three-dimensional geological unconformities, characterized in that: The system is based on the method for constructing a three-dimensional geological unconformity according to any one of claims 1-2. The system includes a data input module, a data extraction module connected to the output end of the data input module, a data classification module connected to the output end of the data extraction module, a data fusion module connected to the output end of the data classification module, a surface construction module connected to the output end of the data fusion module, and a surface output module connected to the output end of the surface construction module. The data input module is used to input geological map vector data and borehole stratigraphic logging data; The data extraction module is used to identify unconformity boundaries and unconformity surfaces, and to extract unconformity lines and unconformity points. The data classification module is used to classify the extracted unconformity construction lines and unconformity construction points according to the same property. The data fusion module is used to fuse unconformity construction lines and unconformity construction points of the same category to form three-dimensional point sets of different categories. The surface construction module is used to construct a triangular mesh surface by triangulating a defined area based on a three-dimensional point set as input data, and to complete the surface spatial morphology correction. The corrected surface is the unconformity surface. The surface output module is used to output the constructed unconformity surface.

4. The system for constructing a three-dimensional geological unconformity according to claim 3, characterized in that: The geological map vector data is input in shp or mapgis format, and the borehole logging data is input in Excel spreadsheet format.

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