Method for carrying out fault reconstruction and dividing geological blocks by using computational geometry
Through the calculation geometric method, three-dimensional boundary and fault characterization are constructed, which solves the problem that the existing technology is difficult to accurately characterize fault non-planar geometric forms and spatial intersection topological relationships, and realizes the accurate geometric structure characterization of complex geological areas and the automatic division of fault networks, and improves the accuracy of fault distribution analysis and geological block division in geological exploration.
Patent Information
- Application Number
- CN202510313470.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-17
- Publication Date
- 2025-06-27
AI Technical Summary
Existing geological modeling methods are difficult to accurately characterize the fault non-planar geometric forms and spatial cross-cutting topological relationships in multi-level fault cross-cutting scenarios, resulting in grid distortion of fault contact zones, and the cutting order and geometric inclusion relationship between faults cannot be automatically analyzed.
Using the computational geometry method, faults are decomposed and independent geological blocks are formed by constructing three-dimensional boundaries, fault characterization, fault extension, virtual cutting correction, interactive cutting and geological block resolution.
Accurate geometric structure characterization of complex geological areas and automated division of fault networks are achieved, which reduces geometric distortion of geological models and improves the accuracy of fault distribution analysis and geological block division in geological exploration.
Smart Images
Figure CN120219650A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of three-dimensional reconstruction, and particularly relates to a method for dividing geological blocks by using computational geometry for tomographic reconstruction. Background Art
[0002] Faults and structures are extremely important geological elements in the geological field. In safety-related issues, the spatial morphology of faults or structures determines the stability of geological bodies, and thus affects the possibility of slope landslides. In mineral-related issues, it affects the exploration work of mineral resources. Ore-forming structures are helpful for prospecting, while ore-breaking structures can displace ore bodies.
[0003] In existing geological modeling methods, the construction of fault systems and the division of geological blocks mainly adopt the method of discretization based on regular grids or geometric interpolation driven by manual experience. The existing methods mainly have the following limitations: (1) For the scenario of multi-level fault cross-cutting, it is difficult for the regular grid method to accurately represent the non-planar geometric morphology and spatial intersection topological relationship of faults, resulting in grid distortion in the fault contact zone; (2) The traditional discrete fracture network (DFN) modeling depends on the manual definition of fault priorities and cannot automatically analyze the cutting order and geometric inclusion relationship between faults. Especially in the area where thrust faults and strike-slip faults are developed in combination, misclassification of stratigraphic units is likely to occur; (3) When existing interpolation algorithms process the cross-cutting of faults with other geological structures such as strata and intrusive rocks, there are generally problems of geometric non-closure, and it is necessary to repeatedly manually correct topological contradictions. These defects lead to geometric distortion of the geological model near the fault cutting zone. Therefore, it is very necessary to develop a method for dividing geological blocks by using computational geometry for tomographic reconstruction that can solve the above problems. Summary of the Invention
[0004] The purpose of the present invention is to provide a method for dividing geological blocks by using computational geometry for tomographic reconstruction to assist technicians in the evolution of corresponding faults or structures.
[0005] The purpose of the present invention is achieved as follows, including the following steps: S100. Construct a three-dimensional boundary: Set the three-dimensional boundary of the calculation range according to the target area, including the roof, floor, and side surfaces; S200. Fault characterization: Within the three-dimensional boundary range, use the trace method to characterize thin faults and thick faults, and generate structural surfaces or structural bodies; among them, the processing process of thin faults is to input the top trace of the fault and record the dip and dip angle at the nodes, and the processing process of thick faults is to use two layers of traces or closed traces for faults with thickness (such as fracture zones) to form a strip-shaped geometric body; S300, Fault Extension: Naturally extend the fault from both ends to intersect with the calculation range, and obtain the geometric structure of the fault extending to the boundary of the calculation range to ensure the geometric integrity of the fault; S400, Virtual Cutting Correction: According to the intersection relationship between the fault and the calculation range, the faults are divided into three categories. The fault whose two ends of the fault fold intersect with the calculation range respectively is determined as a fully penetrated fault. The fault whose fault fold intersects with the calculation range at only one end is determined as a semi-penetrated fault. The fault whose two ends of the fault fold do not intersect with the calculation range is determined as a small fault within the calculation range. For semi-penetrated faults or small faults, use virtual cutting planes to cut and correct their spatial dimensions; For semi-penetrated or small faults, since there are fold ends that do not extend to the boundary of the calculation range, virtual cutting planes are provided to assist in determining their boundaries. These virtual cutting planes assist in simulating the range of semi-penetrated faults or small faults. In terms of input methods, they follow a simple principle. They can be determined using a parametric method in mathematics or can be quickly determined according to the existing fault or terrain distribution to obtain their spatial postures and parameters; S500, Interactive Cutting: Select two fault folds, one fold as the cutting plane and the other as the cut plane. After performing the cutting calculation, interactively determine one section as the retained plane and the other section as the discarded plane. Repeat the cutting steps until all faults are cut to form an independent fault network; In actual work, faults have a chronological relationship due to different formation ages. To better infer the cutting relationship of faults, it is allowed to interactively determine the cutting plane and the cut plane to simulate the chronological relationship in reality. For the two components after cutting the cut plane, the retained component can be regarded as the current fault, and the discarded fault can be corresponded to the fault after the land block is uplifted, so it is stored in the database for subsequent analysis of land block uplift and other uses. For repeated cutting, due to the non-direct observability of faults, the internal cutting distribution cannot be fully understood. Therefore, this method allows the fault cutting simulation to be repeated. Select the cut plane and the cutting plane and loop until the cutting result meets the fault distribution representation. This process can be repeated multiple times to approximate the current distribution of faults; S600, Geological Block Resolution: Based on the cut fault network and the three-dimensional boundary, resolve the closed geological blocks to obtain each independent geological block surrounded by the faults and the boundary of the calculation range. The geological blocks are output in the form of closed geometric bodies; After the calculation in step S500, the spatial distribution of the faults is obtained. In step S600, based on the fault distribution, automatic calculation is performed within the calculation range to determine the geological blocks formed after being cut by the faults. The geological blocks are output in the form of closed geometric bodies, and these closed geometric bodies have important application values; S700, Data Processing within the Block: Inside the geological block, if there is borehole data, automatic topological connection of the ore seams is carried out within this area and extended to the boundary of the geological block; if there is no borehole data, step S700 is skipped. For step S700, if there is borehole data within the closed geometry, automatic 3D reconstruction of geological elements within this area and determination of the topological connection relationship can be achieved.
[0006] Preferably, the calculation range in step S100 is the pure coordinate range of the mining right boundary or the research area, and the roof, floor, and sides are all bounded areas.
[0007] Preferably, the input methods for the trace line, node dip, and dip angle parameters of the fault in step S200 are graphical input or file input. Both of these methods follow simple principles and at the same time provide relatively high-level tools to assist in the rapid input of faults and automatic calculation of boundaries.
[0008] Preferably, the discarded surface data in step S500 is used to analyze the uplift condition of the plot. Specifically: using the discarded surface data, calculate the uplift amount and displacement direction caused by fault dislocation; in practice, the discarded surface usually occurs when the plot is uplifted and displaced. By studying the discarded fault components, phenomena such as the uplift of the relevant plot can be analyzed. After determining this parameter, it usually helps to analyze the uplift and migration of the relevant strata or mineral resources, etc., providing technical support for the corresponding exploration work.
[0009] Compared with the prior art, the present invention has the following technical effects: 1. The present invention mathematizes the information of complex geological regions into geometric structures, uses fault information within the regional scope for block division calculation, classifies faults into fully penetrated, semi-penetrated, and small faults to study the chronological order of fault formation, interactively determines the cutting sequence of faults and performs corresponding cutting operations, and finally forms independent geological blocks cut by faults within the calculation area. In this independent geological block, the topological connection of data obtained by means such as boreholes becomes simple, thus providing a basis for automatic construction for the shape analysis of geological elements in geological exploration, and an interactive version can also be realized, providing a means for simulating the actual evolution process of faults in the computer; 2. The present invention does not directly focus on the modeling of geological elements, but directly analyzes the geometric forms of the core factors, faults or structures, that affect geological elements. The analysis and calculation amount for this core element is smaller than that of analyzing all cataloged geological data, and the calculation results are more reliable; 3. The geological blocks calculated by the present invention are complete blocks formed under the control of faults or structures. Within this block, geological elements can be regarded as not being damaged, which is conducive to subsequent rapid and continuous modeling of geological elements within this block, and the modeling results meet the geological constraint conditions. 4. The discarded fault component data obtained by the method of the present invention can be used as a basis for calculating the dislocation parameters of the plot. This discarded component was originally a fault or structure, which was dislocated after the actual uplift of the plot or geological movement. Calculating this parameter helps to further understand the geological movement in this area, and an unexpected technical effect is produced. BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Figure 1 is a schematic flow chart of the method of the present invention; Figure 2 is an effect diagram of generating a structural surface and a structure body using a trace line in Embodiment 1; Figure 3 is an effect diagram of fault extension in Embodiment 1; Figure 4 is a schematic diagram of fault cutting in Embodiment 1; Figure 5 is a schematic diagram of fault cutting of different ages in Embodiment 1; Figure 6 is a schematic diagram of fault cutting a mineral layer in Embodiment 2; Figure 7 is a schematic diagram of a geological structure in which a mineral layer is cut by faults in multiple periods in Embodiment 2. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0011] The present invention will be further described below in conjunction with the embodiments and the drawings, but the present invention is not limited in any way. Any transformation or replacement based on the teachings of the present invention falls within the protection scope of the present invention.
[0012] Embodiment 1 In the geological element modeling work in the exploration stage of mine resources, the method of using computational geometry to reconstruct faults and divide geological blocks in this embodiment includes the following steps: S100. Construct a three-dimensional boundary: According to the surface elevation data of the exploration area and the top and bottom plate depths revealed by boreholes, set a closed three-dimensional boundary of the calculation range, including the roof, the floor (lower limit of exploration), and the sides; S200. Fault characterization: Within the three-dimensional boundary range, use the trace line method to characterize thin faults and thick faults, and generate a structural surface or a structure body, as shown in Figure 2 ; among them, the processing process of thin faults is to input the trace line of the fault top and input the dip and dip angle at the nodes. The processing process of thick faults is to use two layers of trace lines or closed trace lines for faults with thickness (such as fracture zones) to form a strip-shaped geometric body; S300. Fault extension: Naturally extend the fault from both ends to intersect with the calculation range, and obtain the fault geometric structure extending to the boundary of the calculation range to ensure the geometric integrity of the fault, as shown in Figure 3 ; S400, Virtual cutting correction: According to the intersection relationship between the fault and the calculation range, the faults are divided into three categories. The faults where both ends of the fault fracture surface intersect with the calculation range are determined as fully penetrated faults. The faults where only one end of the fault fracture surface intersects with the calculation range are determined as semi-penetrated faults. The faults where neither end of the fault fracture surface intersects with the calculation range are determined as small faults within the calculation range. For semi-penetrated faults or small faults, virtual cutting planes are used for cutting to correct their spatial dimensions. S500, Interactive cutting: Select two fault fracture surfaces, where one fracture surface is the surface to be cut and the other is the cutting surface. After performing the cutting calculation, interactively determine a section as the retained surface and the other section as the discarded surface based on geological evidence (such as the fault displacement direction revealed by boreholes). Repeat the cutting steps until all faults are cut to form an independent fault network; see Figure 4 , Figure 5 ; S600, Geological block calculation: Based on the cut fault network and the three-dimensional boundary, calculate the closed geological blocks to obtain each independent geological block surrounded by the faults and the calculation range boundary, and the geological block is output in the form of a closed geometric body. S700, Data processing within the block: Inside the geological block, if there is borehole data, then perform automatic topological connection of the ore layers in this area and extend to the boundary of the geological block. If there is no borehole data, skip step S700. For the discarded data, this type of data is the dislocation caused by the uplift of the landmass after the complete fault or structure is misappropriated by reality. Analyzing this type of data helps to obtain the relevant dislocation parameters of the landmass uplift, provides technical support for solving the phenomenon that half of the ore body remains and half disappears after being cut, and for subsequent analysis of the uplift of the relevant strata or mineral resources, or the three-dimensional geological model of the tectonic exploration area.
[0013] Example 2 In the prospecting work after the mineral resources are cut by faults, the method of using computational geometry to reconstruct faults and divide geological blocks in this example includes the following steps: S100, Construct a three-dimensional boundary: According to the known ore body range and fault zone distribution in the target area, set the three-dimensional boundary of the calculation range, including the roof, floor, and sides. S200, Fault characterization: Within the three-dimensional boundary range, use trace lines to characterize thin faults and thick faults, and generate structural surfaces or structural bodies. Among them, the processing process of thin faults is to input the trace line of the fault top and enter the dip and dip angle at the nodes. The processing process of thick faults is to use two layers of trace lines or closed trace lines for faults with thickness (such as fracture zones) to form a strip-shaped geometric body. S300, Fault extension: Naturally extend the faults from both ends to intersect with the calculation range, and obtain the fault geometric structure extending to the boundary of the calculation range to ensure the geometric integrity of the faults. S400, Virtual cutting correction: According to the intersection relationship between the fault and the calculation range, the faults are divided into three categories. The faults whose two ends of the fault plane intersect with the calculation range are determined as fully penetrated faults. The faults whose fault plane intersects with the calculation range at only one end are determined as semi-penetrated faults. The faults whose two ends of the fault plane do not intersect with the calculation range are determined as small faults within the calculation range. For semi-penetrated faults or small faults, virtual cutting planes are used for cutting to correct their spatial dimensions. S500, Interactive cutting: Select two fault planes, one as the plane to be cut and the other as the cutting plane. After performing the cutting calculation, according to geological evidence (such as the fault displacement direction revealed by boreholes), interactively determine one section as the retained surface (known ore body) and the other section as the discarded surface ("disappeared ore body"), as shown in Figure 6 ; Repeat the cutting steps to perform multiple cuts on the remaining parts of the ore body after cutting multiple groups of faults. As Figure 7 shown, faults of different ages have cut the ore body multiple times until all faults are cut to form an independent fault network. S600, Geological block calculation: Based on the cut fault network and the three-dimensional boundary, calculate the closed geological blocks to obtain each independent geological block surrounded by the faults and the boundary of the calculation range. The geological block is output in the form of a closed geometric body. S700, Data processing within the block: Inside the geological block, if there is borehole data, automatic topological connection of the ore layers is carried out in this area and extended to the boundary of the geological block. If there is no borehole data, step S700 is skipped. Analyze the "disappeared ore body" data. Analyzing this type of data helps to obtain relevant dislocation parameters of the land uplift, providing technical support for phenomena such as half of the ore body remaining and half disappearing after being cut. Combining the uplift parameters can infer the relevant formation or ore body resource positions after the fault displacement, providing a basis for deep prospecting.
[0014] Example 3 In the reconstruction work of the underlying elements of the exploration work in the ore target area, the method of using computational geometry in this example to reconstruct faults and divide geological blocks includes the following steps: S100, Construct a three-dimensional boundary: According to the top and bottom coordinates of the exploration target horizon (such as coal seam, ore-bearing layer), set the three-dimensional boundary of the calculation range, including the roof, floor, and sides. S200, Fault characterization: Within the three-dimensional boundary range, use double-layer traces or closed traces to characterize thin faults and thick faults, and generate structural surfaces or structural bodies. Among them, the processing process of thin faults is to input the top trace of the fault and enter the dip and dip angle at the nodes. The processing process of thick faults is to use two-layer traces or closed traces for faults with thickness (such as fracture zones) to form a strip-shaped geometric body. S300, Fault Extension: Naturally extend the fault from both ends to intersect with the calculation range, and obtain the geometric structure of the fault extending to the boundary of the calculation range to ensure the geometric integrity of the fault; S400, Virtual Cutting Correction: According to the intersection relationship between the fault and the calculation range, the faults are divided into three categories. The fault whose two ends of the fault surface intersect with the calculation range respectively is determined as a fully penetrated fault. The fault whose fault surface intersects with the calculation range at only one end is determined as a semi-penetrated fault. The fault whose two ends of the fault surface do not intersect with the calculation range is determined as a small fault within the calculation range. For semi-penetrated faults or small faults, use virtual cutting planes to cut and correct their spatial dimensions; S500, Interactive Cutting: Select two fault surfaces, one of which is the surface to be cut and the other is the cutting surface. After performing the cutting calculation, interactively determine one section as the retained surface and the other section as the discarded surface. Repeat the cutting steps until all faults are cut to form an independent fault network; S600, Geological Block Solving: Based on the cut fault network and the three-dimensional boundary, solve the closed geological blocks to obtain each independent geological block surrounded by the fault and the boundary of the calculation range, and output the geological block in the form of a closed geometric body; S700, Data Processing within the Block: Inside the geological block, if there is drilling data, perform automatic topological connection of the ore layers in this area and extend to the boundary of the geological block. If there is no drilling data, skip step S700; Analyze the discarded formation data, calculate the uplift amount and displacement direction caused by fault dislocation. Adjust the spatial position of the fault based on the uplift parameters to make the reconstructed model consistent with the actual exploration evidence.
Claims
1. A method for fault reconstruction and division of geological blocks using computational geometry, characterized in that The following steps are involved: S100, constructing a three-dimensional boundary: according to the target area, setting the three-dimensional boundary of the calculation range, including the top plate, the bottom plate and the side; S200, fault characterization: within the three-dimensional boundary, thin faults and thick faults are characterized by using traces, and structural surfaces or structural bodies are generated; the processing process of thin faults is to input the top trace of the fault and enter the dip and inclination at the node; the processing process of thick faults is to use two layers of traces or closed traces for the faults with thickness to form a belt-shaped geometry; S300, fault extension: The fault is naturally extended from both ends to intersect with the calculation range, and the fault geometry extending to the boundary of the calculation range is obtained to ensure the geometric integrity of the fault; S400, virtual cutting correction: according to the intersection relationship between the fault and the calculation range, the fault is divided into three categories, the fault whose two ends of the fault fold surface intersect with the calculation range is determined as a full-through fault, the fault whose only one end of the fault fold surface intersects with the calculation range is determined as a semi-through fault, and the fault whose two ends of the fault fold surface do not intersect with the calculation range is determined as a small fault within the calculation range; for semi-through faults or small faults, a virtual cutting plane is used for cutting to correct their spatial size; S500, interactive fault cutting: select two fault folds, one of which is the to-be-cut surface and the other is the cutting surface, and after performing cutting calculation, interactively determine one section as the retained surface and the other section as the discarded surface; repeat the cutting steps until all faults are cut to form a mutually independent fault network; S600, geological block solution: based on the cut fault network and three-dimensional boundaries, the closed geological block is solved to obtain each independent geological block surrounded by the fault and the calculation range boundary, and the geological block is output in the form of a closed geometric body; S700, data processing within the block: within the geological block, if there is drilling data, the topology of the ore layer is automatically connected in the area and extended to the boundary of the geological block; if there is no drilling data, step S700 is skipped.
2. The method for partitioning geological blocks by fault reconstruction using computational geometry according to claim 1, characterized in that The calculation range described in step S100 is the pure coordinate range of the mining right boundary or the research area, and the top plate, bottom plate and side are all bounded areas.
3. The method for partitioning geological blocks by fault reconstruction using computational geometry according to claim 1, characterized in that In step S200, the input method of the fault trace, node dip and inclination parameters is graphic input or file input.
4. The method for partitioning geological blocks by fault reconstruction using computational geometry according to claim 1, characterized in that In step S500, the discarded surface data is used to analyze the uplift status of the land block, specifically: the uplift amount and displacement direction caused by the fault dislocation are calculated using the discarded surface data.