A method for three-dimensional modeling and visualization of geological structures

Abstract

The application discloses a geological structure three-dimensional modeling and visualization method, relates to the technical field of three-dimensional image modeling, and comprises the following steps: acquiring multi-source geological structure data of a target region and unifying a space reference, generating a borehole horizon point set, a profile stratigraphic line set, a fault control line set, a fault attribute table and a stratigraphic sequence table; generating an initial fault surface and extracting an upper wall and a lower wall cutting line, establishing a fault cutting line candidate dual graph, and identifying a dual wrong sequence type false closed unit; removing a wrong closed connection, rebuilding a fault neighborhood stratigraphic interface, and generating a three-dimensional geological structure model and a visualization result. The application can reduce the false connection of strata on both sides of a fault and the false extension of a structural interface, and improve the topological reliability and interpretability of a three-dimensional geological model.

Description

Technical Field

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

[0002] Three-dimensional modeling and visualization of geological structures have become important technical means to express subsurface stratigraphic interfaces, fault planes, structural contact relationships, and the spatial distribution of geological bodies. Existing methods typically acquire borehole layer data, geological profile data, surface geological map data, geophysical interpretation line data, and fault interpretation data, and generate subsurface geological structure models through unified coordinate transformation, fault plane fitting, stratigraphic interface interpolation, and three-dimensional visualization rendering to assist in engineering design, resource assessment, and risk analysis. However, in fault-developed areas, stratigraphic interfaces are often cut by faults and undergo displacement, duplication, loss, or inversion. The stratigraphic boundaries on both sides of the fault no longer represent a simple continuous relationship, but need to accurately express the spatial correspondence and geological sequence relationship between the hanging wall and footwall.

[0003] Many 3D geological structural modeling methods focus on the geometric fitting accuracy of fault planes, the continuous interpolation effect of stratigraphic surfaces, or the display effect of 3D models. When dealing with the truncation relationship between the strata on both sides of a fault, they tend to directly pair the hanging wall truncation line with the footwall truncation line based on spatial proximity or surface closure. However, due to the fact that actual geological data usually has problems such as sparse boreholes, large profile spacing, uncertainties in geophysical interpretation, and inconsistent accuracy of different data sources, existing methods are difficult to reliably identify the true dual relationship between the truncation lines on both sides of the same fault plane. This can easily lead to false closure of fault truncation lines with misaligned duality. That is, the 3D model presents a continuous, closed, and smooth structural surface in visualization, but in reality, there are problems such as misconnection of strata on both sides of the fault, false extension of structural interfaces, and distortion of geological topological relationships, which affect the reliability of subsequent engineering interpretation, risk assessment, and geological decision-making. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies, such as the difficulty in identifying the true duality of the truncation lines on both sides of the fault in the fault development area, which leads to the formation of a three-dimensional model with a closed surface but distorted geological topological relationships. Therefore, this invention proposes a three-dimensional modeling and visualization method for geological structures.

[0005] To address the problems existing in the prior art, the present invention adopts the following technical solution: A method for three-dimensional modeling and visualization of geological structures, comprising: S1 acquires multi-source geological structure data of the target area, unifies the spatial benchmark, and generates a set of borehole site locations, a set of profile stratigraphic lines, a set of fault control lines, a fault attribute table, and a stratigraphic sequence table. S2 generates an initial fault plane set based on the fault control line set, and extracts the hanging wall truncation line set and the footwall truncation line set on both sides of the initial fault plane; S3 establishes a candidate dual diagram of fault truncation lines based on the fault attribute table, stratigraphic sequence table, hanging wall truncation line set, and footwall truncation line set; S4 identifies fault truncation line dual misordered pseudo-closed units based on the fault truncation line candidate dual diagram, fault attribute table and stratigraphic sequence table, and generates a set of pseudo-closed units to be corrected. S5 removes erroneous closed connections based on the set of pseudo-closed units to be corrected and the candidate dual diagram of fault truncation lines. It then reconstructs the stratigraphic interfaces in the fault neighborhood by combining the set of borehole site locations, the set of profile stratigraphic lines, the stratigraphic sequence list, and the set of initial fault planes. This generates a set of corrected truncation line dual relationships, a set of corrected stratigraphic interfaces, and a set of unconfirmed truncation line boundaries. S6 performs geological topological consistency verification based on the initial fault plane set, the corrected stratigraphic interface set, and the unconfirmed truncation line boundary set, and generates a three-dimensional geological structure model. S7 generates 3D visualization results based on the 3D geological structure model, the set of pseudo-closed units to be corrected, the set of corrected cut-off line duality relations, and the set of unconfirmed cut-off line boundaries.

[0006] Preferably, the multi-source geological structural data includes borehole stratification data, geological profile data, surface geological map data, geophysical interpretation line data, and fault interpretation data; the borehole stratification data includes borehole coordinates, borehole depth, stratigraphic number, and stratum boundary depth; the geological profile data includes profile location, profile direction, stratigraphic boundaries within the profile, and fault lines; the fault interpretation data includes fault name, fault strike, dip, dip angle, fault nature, fault control points, and fault control lines; the fault attribute table is generated based on the fault interpretation data and includes fault nature and fault displacement variation information determined by the geological profile data; the fault control line set is generated based on the fault control points and fault control lines; the stratigraphic sequence table is established based on the stratigraphic order and the stratigraphic missing, stratigraphic duplicate, or stratigraphic inversion relationships marked by the geological profile data.

[0007] Preferably, generating an initial fault plane set based on the fault control line set includes: Initial fault planes are generated using triangular mesh surface fitting, spline surface fitting, or implicit surface fitting. The stratigraphic interface constraint location is determined based on the stratigraphic profile set and the borehole site set. The intersection location between the stratigraphic interface constraint location and the initial fault plane is identified and the fault cut-off line is extracted. The wall-side attributes of each fault cut-off line are determined based on the normal vector of the initial fault plane and the spatial relationship between the points on both sides of the fault. The wall-side attributes are either the hanging wall or the footwall. Based on the side properties, a set of upper plate cutting lines and a set of lower plate cutting lines are formed.

[0008] Preferably, establishing a candidate dual diagram of the fault truncation line includes: Within the same initial fault plane, the hanging wall tangent is used as the first type of node and the hanging wall tangent as the second type of node. Candidate edges are established between the hanging wall tangent and the hanging wall tangent that meet the candidate pairing conditions to obtain the candidate dual diagram of the fault tangent. The candidate pairing conditions include sequence consistency constraints, arrangement constraints along the fault strike, and fault displacement constraints.

[0009] Preferably, the sequence consistency constraint is that the hanging wall truncation line and the footwall truncation line connected by the candidate edges correspond to the same stratigraphic interface, or satisfy the stratigraphic relationships allowed in the stratigraphic sequence table, such as stratigraphic missing, stratigraphic repetition, or stratigraphic inversion; the fault strike alignment constraint is that the projection positions of the hanging wall truncation line and the footwall truncation line connected by the candidate edges on the initial fault plane are consistent with the stratigraphic arrangement order in the adjacent geological profile; the fault displacement constraint is that the relative positions between the hanging wall truncation line and the footwall truncation line connected by the candidate edges satisfy the fault properties and fault displacement variation information in the fault attribute table.

[0010] Preferably, identifying the dual-disorder type false closed unit of the fault truncation line includes: In the candidate dual diagram of fault truncation lines, the hanging wall truncation lines and footwall truncation lines are sorted along the fault strike respectively; When the hanging wall truncation lines are adjacent in the sorting, but the corresponding footwall truncation lines of their candidates show order reversal, cross-layer connection or non-adjacent jump connection, and cannot be explained by the fault attribute table and stratigraphic sequence table, it is determined that there is a risk of fault truncation line dual misorder. An initial closed boundary is constructed based on the initial fault plane set, the profile stratigraphic line set, and the candidate dual diagram of fault cut-off lines. When the initial closed boundary is formed by connecting cut-off lines with the risk of fault cut-off line dual misorder, the corresponding region is determined as a false closed unit of fault cut-off line dual misorder.

[0011] Preferably, each false closure unit in the set of false closure units to be corrected includes an out-of-order hanging wall truncation line, a footwall truncation line corresponding to the out-of-order hanging wall truncation line, the initial fault plane to which the false closure unit to be corrected belongs, and the formation interface corresponding to the false closure unit to be corrected.

[0012] Preferably, reconstructing the stratigraphic interface of the fault neighborhood includes: The closed connection formed between the upper truncation line and the lower truncation line corresponding to the error in the set of corrected false closed elements is removed; Based on the candidate dual diagram of fault cut-off lines, the dual relationships of cut-off lines that satisfy sequence consistency constraints, fault strike arrangement constraints, and fault displacement constraints are re-determined, and a set of modified cut-off line dual relationships is generated. The same stratigraphic interface terminates at the initial fault plane at the fault, and the geological duality between the hanging wall truncation line and the footwall truncation line is preserved without geometric welding. A modified stratigraphic interface set is generated based on the borehole site set, the profile stratigraphic line set, the stratigraphic sequence list and the initial fault plane set. For cut lines whose duality cannot be determined, generate a set of unconfirmed cut line boundaries.

[0013] Preferably, a geological topological consistency verification is performed, including: Check whether the same stratigraphic interface incorrectly crosses the initial fault plane at the fault location; Check for sequence inversions between adjacent stratigraphic interfaces that cannot be explained by the stratigraphic sequence table; Check whether there is any misconnection between the hanging wall and footwall at the corresponding stratigraphic interfaces on both sides of the fault. Examine whether the geological body enclosed by the initial fault plane and the modified stratigraphic interface set contains a false closed block caused by a truncation line with a risk of dual misorder of fault truncation lines; When the verification fails, the location of the failed verification is mapped to the set of pseudo-closed units to be corrected, and the stratigraphic interface of the fault neighborhood is reconstructed.

[0014] Preferably, generating a 3D visualization result includes: Generate rotatable, cross-sectional, and queryable 3D geological structure visualization results based on the 3D geological structure model; The visualization results of the three-dimensional geological structure show the set of dual relationships of fault planes, stratigraphic interfaces, hanging wall truncation lines, footwall truncation lines, and modified truncation lines in the three-dimensional geological structure model. The system displays prompts for sets of pseudo-closed elements to be corrected, identifies sets of dual relations of corrected tangent lines, and displays uncertain boundaries for sets of unconfirmed tangent line boundaries.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention acquires borehole stratification data, geological profile data, surface geological map data, geophysical interpretation line data, and fault interpretation data, and unifies the spatial benchmark. It first generates an initial fault plane, then extracts the hanging wall and footwall truncation lines on both sides of the fault, further establishing a candidate dual diagram of the fault truncation lines. This transforms the stratigraphic correspondence on both sides of the fault, which is difficult to directly identify in existing technologies, into a verifiable and identifiable truncation line dual relationship. By jointly screening candidate relationships through sequence consistency constraints, fault strike arrangement constraints, and fault displacement constraints, it avoids incorrectly connecting the stratigraphic interfaces on both sides of the fault based solely on spatial proximity or surface continuity. This solves the problem of erroneous connection of strata on both sides of the fault and false extension of structural interfaces caused by factors such as sparse boreholes, large profile spacing, and inconsistent data accuracy, thus improving the geological rationality of the three-dimensional geological structural model of the fault development area.

[0016] 2. This invention also identifies fault-related misaligned false closed units by identifying fault truncation lines, removes erroneous closure connections, and reconstructs stratigraphic interfaces within the fault neighborhood, ensuring that the same stratigraphic interface terminates at the initial fault plane at the fault, rather than directly interpolating across fault planes. By correcting the set of truncation line dual relationships, the set of unconfirmed truncation line boundaries, and geological topological consistency verification, it can distinguish between real geological correspondences, previously existing false closure locations, and uncertain boundaries that cannot be reliably closed. This reduces the situation where the 3D model appears continuous on the visual surface but is actually geologically topologically distorted, improving the topological reliability, interpretability, and engineering application credibility of the 3D geological structure model, and providing more reliable 3D structural basis for mineral exploration, underground engineering design, tunnel construction risk analysis, geothermal development, and urban underground space utilization. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 A flowchart illustrating a three-dimensional modeling and visualization method for geological structures provided by this invention; Figure 2 This is a schematic diagram of a dual-disordered false closure of a fault truncation line provided by the present invention; Figure 3 This is a schematic diagram of a candidate dual diagram of a fault truncation line provided by the present invention; Figure 4 This is a schematic diagram illustrating the visualization results of the three-dimensional geological structure model provided by the present invention. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0019] Example 1: This invention provides a three-dimensional modeling and visualization method for geological structures, which is applicable to the reconstruction and visualization of three-dimensional images of geological structures in fault-developed areas. It is especially applicable to geological modeling scenarios where borehole data, geological profiles, surface geological maps, geophysical interpretation lines and fault interpretation data coexist, but there are spatial distribution differences, stratigraphic displacement on both sides of the fault, missing strata, repeated strata or inverted strata. A method for three-dimensional modeling and visualization of geological structures includes the following steps; S1. Obtain multi-source geological structure data of the target area, unify the spatial benchmark, and generate a set of borehole site locations, a set of profile stratigraphic lines, a set of fault control lines, a fault attribute table, and a stratigraphic sequence table. In this step, the target area is the area with fault structure that needs to be modeled in three dimensions. The target area includes mining areas, tunnel route areas, underground engineering site areas, geothermal reservoir areas, oil and gas reservoir areas, or urban underground space development areas. There is at least one fault in the target area, and at least one stratigraphic interface is cut by the fault. Acquire multi-source geological structural data of the target area; the multi-source geological structural data includes borehole layer data, geological profile data, surface geological map data, geophysical interpretation line data, and fault interpretation data; The borehole stratification data includes borehole coordinates, borehole depth, stratum number, and stratum boundary depth. The borehole coordinates are used to determine the location of the borehole in the three-dimensional space of the target area, the borehole depth is used to determine the extension range of the borehole along the depth direction, the stratum number is used to identify the strata that appear in the borehole, and the stratum boundary depth is used to indicate the interface position between adjacent strata. Geological profile data includes profile location, profile direction, stratigraphic boundaries within the profile, and fault lines. Profile location is used to determine the spatial location of the geological profile in the target area, profile direction is used to determine the direction of profile development, stratigraphic boundaries within the profile are used to indicate the boundaries of different strata in the profile, and fault lines are used to indicate the location of faults exposed or interpreted in the profile. Surface geological map data includes surface stratigraphic boundaries, surface fault traces, and surface structural boundaries; geophysical interpretation line data includes subsurface boundaries, fault anomaly lines, or structural anomaly lines obtained from seismic, electrical, magnetic, gravity, or other geophysical interpretations; fault interpretation data includes fault name, fault strike, dip, dip angle, fault nature, fault control points, and fault control lines; fault nature includes normal faults, reverse faults, strike-slip faults, or faults with combined movement characteristics; The aforementioned multi-source geological structural data underwent spatial benchmark unification processing. This process included unifying the coordinate system, elevation benchmark, depth direction, and data scale. Coordinate mapping was performed on geological profile data and surface geological map data to transform stratigraphic boundaries and fault lines within the profiles to the three-dimensional coordinate system of the target area. Borehole layer data underwent borehole coordinate and layer boundary depth transformation to ensure that each layer boundary depth corresponds to a three-dimensional spatial point. Geophysical interpretation line data underwent coordinate transformation and depth registration to ensure that geophysical interpretation lines, borehole layer locations, and profile stratigraphic lines are located under the same spatial benchmark.

[0020] A set of borehole layer sites is generated based on borehole stratification data; specifically, the depth of each layer boundary in each borehole is converted into a three-dimensional coordinate point, and the three-dimensional coordinate point is associated with the corresponding stratum number to obtain the borehole layer site; all borehole layer sites constitute the set of borehole layer sites. A set of stratigraphic lines is generated based on geological profile data. Specifically, the stratigraphic boundaries in each geological profile are converted into three-dimensional coordinate lines, and these three-dimensional coordinate lines are associated with the corresponding stratigraphic numbers or stratigraphic interface numbers to obtain the stratigraphic lines. All stratigraphic lines constitute the set of stratigraphic lines. A set of fault control lines is generated based on fault interpretation data. Specifically, when fault control lines exist in the fault interpretation data, they are transformed to a unified three-dimensional coordinate system. When fault control points exist in the fault interpretation data, fault control points belonging to the same fault are connected to form fault control lines based on the same fault name, the same fault strike, or the fault interpretation relationship within the same geological profile. All fault control lines obtained from fault control points and fault control lines constitute a set of fault control lines. In this embodiment, the borehole layer site set refers to the set of three-dimensional layer sites obtained by converting the layer boundary depth in each borehole. Each borehole layer site corresponds to at least one borehole number, one stratigraphic number, and one three-dimensional spatial location. The profile stratigraphic line set refers to the set of three-dimensional linear constraints obtained by converting the stratigraphic boundaries in the geological profile. Each profile stratigraphic line is used to constrain the spatial morphology of the corresponding stratigraphic interface within the profile. The fault control line set refers to the set of fault spatial constraints formed by fault control points and fault control lines under a unified spatial reference, which is used to generate the initial fault plane. The fault attribute table refers to a data table that records fault name, fault nature, fault attitude, and fault displacement variation information. The stratigraphic sequence table refers to a data table that records the stratigraphic order and stratigraphic missing, stratigraphic repeat, or stratigraphic inversion relationships, which is used to subsequently determine whether the stratigraphic relationship between the cut-off lines can be interpreted by the geological sequence.

[0021] A fault attribute table is generated based on fault interpretation data and geological profile data. The fault attribute table records the fault name, fault strike, dip direction, dip angle, fault nature, and fault displacement variation information for each fault. The fault displacement variation information is determined based on the relative displacement of the same stratigraphic interface on both sides of the fault in the geological profile. When multiple geological profiles reveal the same fault, the fault displacement variation relationship along the strike direction is recorded according to the profile location. The fault displacement information is determined according to the location of the same stratigraphic interface on both sides of the fault within the same geological profile. Specifically, within the same geological profile, the intersection points of the same stratigraphic interface on the hanging wall and the footwall are selected and denoted as the hanging wall boundary intersection point and the footwall boundary intersection point, respectively. The fault displacement vector at this profile is obtained based on their relative positions in a unified three-dimensional coordinate system. The fault displacement vector is decomposed into a vertical component, a horizontal projection component, and a projection component along the fault dip direction. The vertical component represents the elevation displacement of the same stratigraphic interface on both sides of the fault, the horizontal projection component represents the planar displacement of the same stratigraphic interface on both sides of the fault, and the projection component along the fault dip direction represents the relative displacement of the same stratigraphic interface on both sides of the fault along the fault dip direction. When the same fault has the same stratigraphic interface at the hanging wall boundary and the footwall boundary in multiple geological profiles, the fault displacement vector and its components are recorded according to the projection position of each geological profile along the fault strike, forming the fault displacement variation information along the strike direction. If there is no complete stratigraphic interface at the fault boundary on both sides of a geological profile, the fault displacement variation information is not determined separately for that geological profile, but is used as a spatial constraint for subsequent determination of the dual relationship of the truncation line.

[0022] A stratigraphic sequence table is established based on the stratigraphic order and stratigraphic missing, overlapping, or inverted relationships marked by geological profile data. The stratigraphic sequence table records the stratigraphic sequence relationships of various stratigraphic interfaces within the target area, and records permissible sequence changes caused by faults, folds, or stratigraphic inversions. The stratigraphic sequence table is used to subsequently determine whether the hanging wall truncation line and the footwall truncation line correspond to the same stratigraphic interface, or whether they belong to permissible stratigraphic missing, overlapping, or inverted relationships. In addition to recording the stratigraphic sequence relationships of various stratigraphic interfaces, the stratigraphic sequence table also records stratigraphic missing relationships, stratigraphic repeat relationships, and stratigraphic inversion relationships already marked in the geological profile data. Stratigraphic missing relationships indicate that a stratigraphic interface does not appear in a local area, but the strata above and below it still maintain an interpretable sequence. Stratigraphic repeat relationships indicate that the same stratigraphic interface appears repeatedly in the profile due to folding or reverse faulting. Stratigraphic inversion relationships indicate that the vertical order of adjacent stratigraphic interfaces is reversed in a local area. Cross-stratigraphic correspondences not recorded in the stratigraphic sequence table are not considered as permissible stratigraphic relationships.

[0023] This step outputs a set of borehole locations, a set of stratigraphic profiles, a set of fault control lines, a fault attribute table, and a stratigraphic sequence table. Among these, the set of borehole locations, the set of stratigraphic profiles, and the set of fault control lines are used to generate the initial fault plane and reconstruct the stratigraphic interface of the fault neighborhood. The fault attribute table and the stratigraphic sequence table are used to establish candidate dual diagrams of fault cut-off lines and to identify falsely closed units of fault cut-off line dual misordered types.

[0024] S2. Generate an initial fault plane set based on the fault control line set, and extract the hanging wall truncation line set and footwall truncation line set on both sides of the initial fault plane. In this step, for each fault control line in the fault control line set, the corresponding fault name and fault attribute are determined; for fault control lines belonging to the same fault, they are used as spatial constraints of the same initial fault plane; an initial fault plane set is generated based on the fault control line set, and the initial fault plane set includes at least one initial fault plane. The initial fault plane is generated using triangular mesh surface fitting, spline surface fitting, or implicit surface fitting. When using triangular mesh surface fitting, control points on the fault control line are used as triangular mesh nodes, and a continuous triangular mesh surface is constructed based on the fault strike and dip constraints. When using spline surface fitting, the fault control line is used as the surface control line to generate a smooth fault surface that passes through or approximates the fault control line. When using implicit surface fitting, the fault control points and fault control lines are used as zero-value constraints to construct an implicit function and extract the zero-value surface as the initial fault plane. The initial fault plane serves as a discontinuous boundary for the reconstruction of the stratigraphic interface in the subsequent modeling process; that is, within the fault neighborhood, the stratigraphic interface does not directly cross the initial fault plane for continuous interpolation, but uses the initial fault plane as the termination boundary or dividing boundary; in this embodiment, the fault neighborhood refers to the local modeling area jointly defined by the initial fault plane, the stratigraphic profile line intersecting with the initial fault plane, and the borehole sites located on both sides of the initial fault plane and participating in the extraction of the cut-off line. The stratigraphic interface constraint location is determined based on the stratigraphic profile set and the borehole site set; specifically, stratigraphic profiles and borehole sites with the same stratigraphic interface number are assigned to the same stratigraphic interface constraint group, and each stratigraphic interface constraint group represents the spatial constraint location of a stratigraphic interface to be reconstructed. The intersection of the stratigraphic interface constraint location with the initial fault plane is identified and the fault cut-off line is extracted. In this embodiment, the fault cut-off line refers to the linear boundary formed in the neighborhood of the initial fault plane after the stratigraphic interface constraint location intersects with the initial fault plane. The fault cut-off line is not an ordinary stratigraphic boundary, but represents the terminating boundary in the neighborhood of the fault after the stratigraphic interface is cut by the fault. It is used to determine whether the stratigraphic interfaces on both sides of the fault are incorrectly connected. Specifically, for the stratigraphic profile, the intersection segments or intersection point sequences between the stratigraphic profile and the initial fault plane are calculated, and the intersection segments or intersection point sequences are connected to form the fault cut-off line; for the borehole site, it is determined whether the borehole site is located in the vicinity of the initial fault plane. When the spatial relationship between the borehole site and the initial fault plane indicates that the stratigraphic interface is cut near the fault, the borehole site is used as the spatial constraint point of the fault cut-off line; combining the intersection position of the stratigraphic profile and the initial fault plane and the constraint of the borehole site, the fault cut-off line of the corresponding stratigraphic interface is formed.

[0025] The wall-side attributes of each fault cut-off line are determined based on the normal vector of the initial fault plane and the spatial relationship between the points on both sides of the fault. The wall-side attributes are either hanging wall or footwall. In this embodiment, the hanging wall cut-off line refers to the fault cut-off line with the wall-side attribute of hanging wall, and the footwall cut-off line refers to the fault cut-off line with the wall-side attribute of footwall. The hanging wall cut-off line and the footwall cut-off line respectively represent the termination boundaries formed at the fault by the stratigraphic interfaces on both sides of the same initial fault plane. The fault cut-off lines are divided into hanging wall cut-off lines and footwall cut-off lines to avoid directly connecting the boundary lines on both sides of the fault that do not belong to the same stratigraphic interface based solely on spatial distance. For any point on the initial fault plane Let the unit normal vector at that point be... The point to be judged is The lateral orientation of the point to be judged relative to the initial fault plane is determined according to the following formula: ; in, The lateral identification symbol is used to indicate the fault side. When multiple points belonging to the same fault have the same lateral identification symbol, the side corresponding to the lateral identification symbol is determined as one side of the fault. Combining the fault dip, dip angle and fault properties, one side is marked as the hanging wall and the other side is marked as the footwall. The fault cut-off line located on the hanging wall side is included in the hanging wall cut-off line set, and the fault cut-off line located on the footwall side is included in the footwall cut-off line set. Each fault cut-off line must record at least its initial fault plane, corresponding stratigraphic interface, spatial coordinate sequence, and sidewall attributes. The initial fault plane is used to determine which fault plane the fault cut-off line participates in the pairing of. The corresponding stratigraphic interface is used to determine the sequence consistency relationship. The spatial coordinate sequence is used for sorting along the fault strike and for visualization. The sidewall attributes are used to distinguish between hanging wall cut-off lines and footwall cut-off lines.

[0026] S3. Based on the fault attribute table, stratigraphic sequence table, hanging wall truncation set and footwall truncation set, establish a candidate dual diagram of fault truncation lines; In this step, a candidate dual graph of fault truncation lines is established for the set of hanging wall truncation lines and the set of footwall truncation lines within the same initial fault plane. In this embodiment, the candidate dual graph of fault truncation lines is a graph structure used to express the candidate correspondence between hanging wall truncation lines and footwall truncation lines. In this graph structure, the hanging wall truncation line is used as a first type of node, the footwall truncation line is used as a second type of node, and the candidate edge indicates that there may be a geological dual relationship between a hanging wall truncation line and a footwall truncation line. The candidate dual graph of fault truncation lines does not directly represent the final geometric connection relationship, but is used to screen the true dual relationship under sequence consistency constraints, fault strike arrangement constraints, and fault displacement constraints. The candidate dual diagram of fault truncation lines is used to represent the possible geological duality between the hanging wall truncation line and the footwall truncation line. In this embodiment, the truncation line duality refers to the relationship between the hanging wall truncation line and the footwall truncation line located on both sides of the same initial fault plane, which satisfies the geological correspondence conditions in terms of corresponding stratigraphic interfaces, arrangement relationship along the fault strike, and fault displacement relationship. The truncation line duality relationship is only used to represent the geological correspondence of the stratigraphic interfaces on both sides of the fault, and does not represent the geometric welding of the hanging wall truncation line and the footwall truncation line into a continuous curved surface. Specifically, within the same initial fault plane, the hanging wall truncation line is used as the first type of node, and the hanging wall truncation line as the second type of node; candidate pairing is performed on any hanging wall truncation line and any hanging wall truncation line; when the hanging wall truncation line and the hanging wall truncation line meet the candidate pairing conditions, a candidate edge is established between them; all the first type of nodes, second type of nodes, and candidate edges constitute a candidate dual diagram of the fault truncation line; as shown... Figure 3 As shown, the candidate dual diagram of fault truncation lines adopts a bipartite graph structure to represent the candidate correspondence between truncation lines on both sides of the same initial fault plane. The left-side nodes represent the hanging wall truncation lines, including hanging wall truncation line 1, hanging wall truncation line 2, and hanging wall truncation line 3; the right-side nodes represent the footwall truncation lines, including footwall truncation line 1, footwall truncation line 2, and footwall truncation line 3. Solid lines in the diagram represent correct candidate edges that meet geological correspondence after being judged by sequence consistency constraints, fault strike alignment constraints, and fault displacement constraints. Dashed lines represent disordered candidate edges with the risk of sequence reversal or cross-layer mismatch. Through this candidate dual diagram, the spatial correspondence between the truncation lines on both sides of the fault can be transformed into a filterable node connection relationship. In subsequent steps, based on whether the candidate edges satisfy sequence consistency, fault strike alignment, and fault displacement relationships, the risk of fault truncation line dual disorder can be identified, and the existence of false closed units of fault truncation line dual disorder can be determined.

[0027] Candidate pairing conditions include sequence consistency constraints, alignment constraints along fault strike, and fault displacement constraints; The sequence consistency constraint is as follows: the hanging wall truncation line and the footwall truncation line connected by the candidate edge must correspond to the same stratigraphic interface, or satisfy the stratigraphic relationship of stratigraphic missing, stratigraphic repeat, or stratigraphic inversion allowed in the stratigraphic sequence table. Specifically, when the stratigraphic interface number corresponding to the hanging wall truncation line is the same as the stratigraphic interface number corresponding to the footwall truncation line, it is determined that the sequence consistency constraint is satisfied. When the stratigraphic interface numbers are different, but the stratigraphic sequence table records the existence of stratigraphic missing, stratigraphic repeat, or stratigraphic inversion at that location, and the stratigraphic relationship between the two is a stratigraphic relationship allowed in the stratigraphic sequence table, it is also determined that the sequence consistency constraint is satisfied. When the two are neither the same stratigraphic interface nor a stratigraphic relationship allowed in the stratigraphic sequence table, it is determined that the sequence consistency constraint is not satisfied. The arrangement constraint along the fault strike is as follows: the projection positions of the hanging wall truncation lines and footwall truncation lines connected by the candidate edges on the initial fault plane are consistent with the stratigraphic arrangement order in the adjacent geological profiles; the adjacent geological profiles refer to two adjacent geological profiles when the intersection lines or intersection points of each geological profile and the same initial fault plane are projected onto the fault strike direction and sorted according to the projection positions; if there are multiple intersecting geological profiles at the same location, the geological profile with a larger angle to the fault strike is selected as the sequence verification profile; when there are two or more geological profiles with the same angle, the geological profile containing more borehole sites is selected as the sequence verification profile; when both the angle and the number of borehole sites are the same, a geological profile is selected as the sequence verification profile according to the geological profile number or the geological profile input order. Specifically, the fault strike unit vector is determined based on the fault strike in the fault attribute table. Select the reference point on the initial fault plane. For representative points on the fault cut-off line Calculate its location parameters along the fault strike: ; in, This indicates the positional parameter of the fault cut-off line along the fault strike; The midpoint or centroid of the spatial coordinate sequence of the fault cut-off line; the hanging wall cut-off lines and footwall cut-off lines are sorted according to the position parameters; if the candidate edge keeps the arrangement order of the same stratigraphic interface between adjacent geological sections consistent, it is determined that the arrangement constraint along the fault strike is satisfied; if the candidate edge reverses the arrangement order of the same stratigraphic interface between adjacent geological sections, and the reversal is not interpreted by the fault attribute table or stratigraphic sequence table, it is determined that the arrangement constraint along the fault strike is not satisfied. The fault displacement constraint is as follows: the relative position between the hanging wall truncation line and the footwall truncation line connecting the candidate edges must satisfy the fault properties and displacement variation information in the fault attribute table. Specifically, when the fault attribute table records the fault as a normal fault, the candidate pairing should conform to the relative displacement relationship between the hanging wall and footwall of a normal fault; when the fault attribute table records the fault as a reverse fault, the candidate pairing should conform to the relative displacement relationship between the hanging wall and footwall of a reverse fault; when the fault attribute table records that the fault has a translational component, the candidate pairing should conform to the relative displacement relationship along the fault strike direction. The displacement variation information is used to constrain the relative displacement variation of the candidate pairing along the fault strike, and the candidate pairing should not contradict the displacement variation direction determined by the geological profile data. When a set of hanging wall truncation lines and footwall truncation lines simultaneously satisfy sequence consistency constraint, fault strike alignment constraint, and fault displacement constraint, a candidate edge is established between them; when at least one constraint is not satisfied, no candidate edge is established.

[0028] S4. Identify fault truncation line dual misordered pseudo-closed units based on the fault truncation line candidate dual diagram, fault attribute table and stratigraphic sequence table, and generate a set of pseudo-closed units to be corrected. In this step, the candidate dual diagrams of the fault truncation line are identified by misorder; the purpose of misorder identification is not to find ordinary geometric gaps, but to identify local structural units that have formed closed or continuous renderings in geometry, but whose closed boundaries are formed by incorrect dual relations. In the candidate dual diagram of fault truncation lines, the hanging wall truncation lines and footwall truncation lines are sorted along the fault strike. The sorting method adopts the position parameter t along the fault strike determined in S3. For the hanging wall truncation lines on the same initial fault plane, the hanging wall truncation line sequence is formed according to t from small to large. For the footwall truncation lines on the same initial fault plane, the footwall truncation line sequence is formed according to t from small to large. Examine the order relationship of candidate edges in the candidate dual diagram of fault truncation lines; when the first hanging wall truncation line and the second hanging wall truncation line are adjacent or maintain a sequential order in the hanging wall truncation line sequence, while the first footwall truncation line and the second footwall truncation line corresponding to their candidates show a reversed order in the footwall truncation line sequence, it is determined that the candidate edge has a risk of order reversal; order reversal means that the first hanging wall truncation line is located before the second hanging wall truncation line, but the first footwall truncation line is located after the second footwall truncation line; Check for cross-layer connection risks; when the hanging wall truncation line and footwall truncation line of the candidate edge do not correspond to the same stratigraphic interface, and the different stratigraphic relationships do not belong to the stratigraphic sequence table's allowed stratigraphic missing, stratigraphic duplicate or stratigraphic inversion relationships, it is determined that the candidate edge has cross-layer connection risks. Check for non-adjacent jump connection risk; when the hanging wall truncation line and the footwall truncation line connected by the candidate edge cross the truncation line corresponding to the intermediate layer in their respective sorting sequences, and this crossing relationship cannot be explained by fault branching, fault properties or fault displacement change information in the fault attribute table, nor by stratigraphic missing, stratigraphic repeat or stratigraphic inversion relationship in the stratigraphic sequence table, it is determined that the candidate edge has a non-adjacent jump connection risk; When the hanging wall truncation lines are adjacent in the sorting, but the corresponding footwall truncation lines of their candidates show order reversal, cross-layer connection or non-adjacent jump connection, and cannot be explained by the fault attribute table and stratigraphic sequence table, it is determined that there is a risk of fault truncation line dual misorder. In this embodiment, the fault truncation line dual misorder risk refers to the candidate correspondence between the hanging wall truncation line and the footwall truncation line represented by the candidate edge. Although they are spatially close or can form a local closed boundary, there is at least one mismatch in the sequence consistency relationship, the arrangement relationship along the fault strike, or the fault displacement relationship that cannot be explained by the fault attribute table and the stratigraphic sequence table. This risk is used to identify candidate relationships that may lead to misconnection of strata on the two sides of the fault before the final three-dimensional geological structure model is formed.

[0029] Among them, those that cannot be explained by the fault attribute table and stratigraphic sequence table can be determined according to the following rules; When the stratigraphic interface numbers corresponding to the hanging wall truncation line and the footwall truncation line connected by the candidate edge are different, and the stratigraphic sequence table does not record an allowed stratigraphic missing relationship, stratigraphic repeat relationship or stratigraphic inversion relationship between the two, it is determined that the candidate edge cannot be interpreted by the stratigraphic sequence table. When the relative displacement direction between the hanging wall and footwall truncation lines corresponding to a candidate edge contradicts the fault properties recorded in the fault attribute table, the candidate edge is determined to be unexplainable by the fault attribute table. Specifically, when the fault property is a normal or reverse fault, the relative displacement direction between the hanging wall and footwall corresponding to the candidate edge is determined based on the vertical component of the displacement vector and the projection component along the fault dip direction to see if it is consistent with the fault property. When the fault property has a strike-slip component, the strike-relative displacement direction corresponding to the candidate edge is determined based on the projection component of the displacement vector along the fault strike direction to see if it is consistent with the strike-slip component direction. If the relative displacement direction corresponding to the candidate edge is opposite to any of the above-mentioned component directions, the relative displacement direction between the hanging wall and footwall truncation lines corresponding to the candidate edge is determined to contradict the fault properties recorded in the fault attribute table. When a candidate edge causes a cross pairing in the fault strike sorting, and the fault attribute table does not record fault branching, fault displacement abrupt change or fault property change, and the stratigraphic sequence table does not record stratigraphic repetition or stratigraphic inversion relationship in the corresponding area, it is determined that the candidate edge cannot be explained by the fault attribute table and stratigraphic sequence table.

[0030] An initial closed boundary is constructed based on the initial fault plane set, the cross-sectional stratigraphic line set, and the candidate dual diagram of the fault truncation line. In this embodiment, the initial closed boundary refers to the local patch boundary formed by connecting the hanging wall truncation line segment, the footwall truncation line segment, the connecting segment of the cross-sectional stratigraphic line in the fault neighborhood, and the virtual connecting segment corresponding to the candidate edge end to end. The initial closed boundary is used to determine whether a locally closed structural region has been formed during the modeling process. The virtual connecting segment in the initial closed boundary is only used to determine whether the candidate dual relationship leads to false closure and is not used as the geometric welded edge in the final three-dimensional geological structural model. The initial closed boundary consists of the hanging wall truncation segment, the footwall truncation segment, the connecting segment of the stratigraphic profile in the fault neighborhood, and the virtual connecting segment corresponding to the candidate edge; the virtual connecting segment is used to represent the candidate dual relationship between the hanging wall truncation line and the footwall truncation line, and is used to determine whether a fault truncation line dual disordered false closed unit is formed, and is not used as the geometric welded edge in the subsequent three-dimensional geological structure model. When the hanging wall truncated segment, hanging wall truncated segment, stratigraphic profile connecting segments within the fault neighborhood, and the virtual connecting segments corresponding to candidate edges are topologically connected end-to-end, forming a local patch boundary, an initial closed boundary is determined to be formed; if this initial closed boundary contains at least one set of candidate edges with fault truncated line dual misorder risk, then the local region corresponding to this initial closed boundary is determined as a fault truncated line dual misorder type false closed unit; Figure 2 As shown, the fault plane divides the geological structure into the hanging wall and footwall. On either side of the fault plane, hanging wall truncation lines 1, 2, and 3 are formed, as are footwall truncation lines 1, 2, and 3. Solid lines in the figure represent stratigraphic interfaces or truncation line locations on both sides of the fault, while dashed lines represent truncation line connections based on spatial proximity or candidate pairings. When candidate connections between the hanging wall and footwall truncation lines exhibit sequential reversal or cross-stratum mismatch, some dashed line connections form locally closed regions near the fault plane. The locally closed region appears geometrically closed or continuous, but its corresponding hanging wall and footwall stratigraphic relationships and fault displacement relationships do not conform to the geological topological relationships defined by the stratigraphic sequence table and fault attribute table. Therefore, it is identified as a dual-disorder type false closed unit. By identifying this dual-disorder type false closed unit, this invention can discover the incorrect pairing relationship of the fault truncation lines on both sides before the generation of the three-dimensional geological structure model, and remove the incorrect closed connections in subsequent steps, avoiding the use of unrealistic closed regions as effective mass boundaries in three-dimensional modeling. If the initial closed boundary does not contain candidate edges with the risk of fault truncation line dual-disorder, then the local region is not identified as a fault truncation line dual-disorder type false closed unit.

[0031] In this embodiment, the fault truncation line dual misorder type false closed unit refers to a local closed region formed by candidate edges with the risk of fault truncation line dual misorder. This local closed region appears as a continuous or closed structural surface in three-dimensional visualization, but there is an incorrect correspondence between the hanging wall truncation line and the footwall truncation line in its closed boundary. Therefore, it should not be used as the boundary of a real geological body to directly participate in the generation of a three-dimensional geological structure model. Each false closure unit to be corrected includes the misordered hanging wall truncation line, the footwall truncation line corresponding to the misordered hanging wall truncation line, the initial fault plane to which the false closure unit to be corrected belongs, and the stratigraphic interface corresponding to the false closure unit to be corrected; the above contents recorded in the false closure unit to be corrected are used to subsequently undo the erroneous closure connection and reconstruct the stratigraphic interface of the fault neighborhood.

[0032] This step outputs a set of false closure units to be corrected. In this embodiment, the set of false closure units to be corrected refers to a data set composed of one or more fault truncation line dual misordered false closure units. Each false closure unit to be corrected records at least the hanging wall truncation line where the misorder occurred, the hanging wall truncation line corresponding to the error, the initial fault plane to which it belongs, and the corresponding stratigraphic interface. This set is used to subsequently remove erroneous closure connections and to indicate the location of over-false closure in the original modeling process in the 3D visualization results.

[0033] S5. Based on the set of false closed units to be corrected and the candidate dual diagram of fault cut-off line, remove the erroneous closed connection, and reconstruct the stratigraphic interface of the fault neighborhood by combining the set of borehole site locations, the set of profile stratigraphic lines, the stratigraphic sequence list and the initial fault plane set, and generate the set of corrected cut-off line dual relations, the set of corrected stratigraphic interfaces and the set of unconfirmed cut-off line boundaries. In this step, for each false closed unit to be corrected in the set of false closed units to be corrected, the closed connection formed between the misordered hanging wall truncation line and the incorrect footwall truncation line is released. Releasing the incorrect closed connection means that during the generation of the three-dimensional geological structure model, the hanging wall truncation line and footwall truncation line corresponding to the group of errors are no longer used as continuous closed boundaries of the same stratigraphic interface, nor are closed geological bodies generated based on the incorrect connection. Based on the candidate dual diagram of fault cut-off lines, the dual relationships of cut-off lines that satisfy sequence consistency constraints, fault strike arrangement constraints, and fault displacement constraints are re-determined. Specifically, candidate edges that are judged to have the risk of fault cut-off line duality are deleted from the candidate dual diagram. Among the remaining candidate edges, candidate edges that simultaneously satisfy the following conditions are selected as the corrected cut-off line dual relationships: the hanging wall cut-off line and the footwall cut-off line connected by the candidate edge satisfy the sequence consistency constraint; the candidate edge does not reverse the order with other determined candidate edges in the fault strike sorting; the candidate edge satisfies the fault properties and fault displacement change information in the fault attribute table; and the candidate edge does not cause the stratigraphic interface to geometrically weld across the initial fault plane.

[0034] When a hanging wall truncation line corresponds to multiple candidate edges satisfying sequence consistency constraint, fault strike alignment constraint, and fault displacement constraint in the candidate dual diagram of fault truncation lines, the modified truncation line duality is determined in the following order: Candidate edges that connect to the same stratigraphic interface number are selected as priority candidate edges; if no candidate edges connect to the same stratigraphic interface number, then candidate edges that satisfy the stratigraphic missing relationship, stratigraphic repeat relationship, or stratigraphic inversion relationship allowed in the stratigraphic sequence table are selected as priority candidate edges. When there are multiple priority candidate edges, the displacement deviation between each priority candidate edge and the displacement change information in the fault attribute table is calculated. The relative displacement between the hanging wall truncation line and the footwall truncation line connected by the candidate edge is determined based on their representative points, which are the midpoint or centroid of the spatial coordinate sequence of the truncation line. This relative displacement is decomposed into vertical components, horizontal projection components, and projection components along the fault dip direction, and compared with the vertical components, horizontal projection components, and projection components along the fault dip direction recorded in the displacement change information at the corresponding fault strike location. When all three components exist, the displacement deviation is the square root of the sum of the squares of the vertical component deviation, the horizontal projection component deviation, and the projection component deviation along the fault dip direction. When one of the components does not exist, the displacement deviation is determined by the square root of the sum of the squares of the remaining component deviations. The priority candidate edge with the smallest displacement deviation is selected as the modified truncation line duality. When there are still two or more candidate edges with the same fault displacement deviation, the candidate edge that will not cross and pair with the already determined modified truncation duality in the sorting along the fault strike is selected as the modified truncation duality. If the dual relationship of the modified cut line cannot be uniquely determined after the above processing, the dual relationship of the cut line of the upper plate or the corresponding lower plate will not be forcibly established, and the cut line that cannot be uniquely determined will be included in the unconfirmed cut line boundary set.

[0035] The candidate edges that meet the above conditions constitute the modified truncation line duality set. In this embodiment, the modified truncation line duality set refers to the set of truncation line dualities re-determined from the remaining candidate edges after deleting candidate edges that have the risk of fault truncation line duality disorder, based on sequence consistency constraints, fault strike arrangement constraints, and fault displacement constraints. The modified truncation line duality set is used to express the geological correspondence between the corrected hanging wall truncation line and the footwall truncation line, and is used for identification display in subsequent three-dimensional visualization results. Each set of modified truncation line dual relationships in the modified truncation line dual relationship set includes at least the hanging wall truncation line, the footwall truncation line, the corresponding stratigraphic interface, the initial fault plane to which it belongs, and the fault displacement deviation; the fault displacement deviation is only used to determine the selection result of the modified truncation line dual relationship and subsequent verification, and is not used to change the original spatial location data in the borehole layer location set, the profile stratigraphic line set, or the initial fault plane set.

[0036] When a hanging wall truncation line or a footwall truncation line does not have a candidate edge that satisfies the above conditions in the candidate dual diagram of fault truncation lines, the establishment of a dual relationship between truncation lines is not forced, and the truncation line is regarded as an unconfirmed truncation line boundary. All unconfirmed truncation line boundaries constitute the unconfirmed truncation line boundary set. In this embodiment, the unconfirmed truncation line boundary set refers to the boundary set formed by truncation lines whose true truncation line dual relationship cannot be uniquely determined in the candidate dual diagram of fault truncation lines. For truncation lines in the unconfirmed truncation line boundary set, the present invention does not force the establishment of a geometric closure relationship between the hanging wall truncation line and the footwall truncation line, but retains them as uncertain boundaries in the subsequent topological consistency verification and three-dimensional visualization results to avoid generating new false closed regions due to insufficient data or multiple solutions.

[0037] The stratigraphic boundaries of the fault neighborhood are reconstructed based on the set of borehole sites, the set of stratigraphic lines in the profile, the stratigraphic sequence list, and the set of initial fault planes; the following rules are followed during the reconstruction process. The same stratigraphic interface terminates at the initial fault plane at the fault, and does not directly cross the initial fault plane for continuous interpolation; that is, when the stratigraphic interface extends to the initial fault plane, the fault cut-off line is used as the termination boundary of the stratigraphic interface, instead of directly connecting the stratigraphic interfaces on both sides of the fault into a continuous curved surface. The geological duality between the hanging wall truncation line and the footwall truncation line is preserved without geometric welding; that is, the set of modified truncation line duality is used to represent the geological correspondence of the same stratigraphic interface on both sides of the fault, but the hanging wall truncation line and the footwall truncation line are not forcibly spliced ​​into the same continuous surface. The extension direction of the stratigraphic interface is jointly constrained by the borehole site set, the profile stratigraphic line set, the stratigraphic sequence list, and the initial fault plane set. The borehole site set is used to constrain the spatial height and stratigraphic position of the stratigraphic interface at the borehole location. The profile stratigraphic line set is used to constrain the morphology of the stratigraphic interface within the profile. The stratigraphic sequence list is used to constrain the vertical order between adjacent stratigraphic interfaces. The initial fault plane set is used to restrict the termination position of the stratigraphic interface at the fault. For cut lines whose duality cannot be determined, closed surfaces are not forcibly generated; instead, they are retained as unconfirmed cut line boundaries. These unconfirmed cut line boundaries are retained in subsequent topology consistency checks and visualization results to avoid the formation of new false closures due to uncertain relationships.

[0038] In the specific reconstruction, either the constrained triangulation reconstruction method or the implicit surface reconstruction method is used to generate a set of corrected stratigraphic interfaces. When using the constrained triangulation reconstruction method, the borehole site and the stratigraphic profile are used as nodes or constraint edges of the triangulation network, the fault cut-off line is used as the boundary line, and the initial fault plane is used as the uncrossable boundary to generate a triangulation surface of the stratigraphic interface in the fault neighborhood. When using the implicit surface reconstruction method, the borehole site and the stratigraphic profile are used as spatial constraints of the stratigraphic interface, and the initial fault plane is used as a discontinuity constraint. Implicit surfaces of the stratigraphic interface are generated on both sides of the initial fault plane and terminate at the fault cut-off line.

[0039] S6. Perform geological topological consistency verification based on the initial fault plane set, the modified cut-off line duality set, the modified stratigraphic interface set, and the unconfirmed cut-off line boundary set, and generate a three-dimensional geological structure model. In this step, a geological topological consistency check is performed on the initial fault plane set, the modified truncation line duality set, the modified stratigraphic interface set, and the unconfirmed truncation line boundary set. In this embodiment, the geological topological consistency check refers to checking the spatial connectivity between the initial fault plane set, the modified stratigraphic interface set, the modified truncation line duality set, and the unconfirmed truncation line boundary set to determine whether the three-dimensional geological structure model still has stratigraphic interfaces that incorrectly cross the initial fault plane, misconnections between the hanging wall and footwall on both sides of the fault, sequence reversals that cannot be explained by the stratigraphic sequence table, and false closed blocks caused by misordered truncation lines. This check is different from a simple geometric integrity check, as it simultaneously considers stratigraphic sequence, fault displacement, and the correspondence between the hanging wall and footwall. Check whether the same stratigraphic interface incorrectly crosses the initial fault plane at the fault. Specifically, take each modified stratigraphic interface in the modified stratigraphic interface set as the inspection object and check its surface mesh patch or surface boundary relationship. If the same surface mesh patch of the same modified stratigraphic interface contains nodes located on both sides of the same initial fault plane, and the boundary of the surface mesh patch does not use the fault truncated line as the termination boundary, then it is determined that the modified stratigraphic interface incorrectly crosses the initial fault plane at the fault. If the same modified stratigraphic interface forms surface parts on both sides of the initial fault plane, and each surface part uses the corresponding fault truncated line as the termination boundary, then it is determined that there is no incorrect crossing. Check whether there is a sequence reversal between adjacent stratigraphic interfaces that cannot be explained by the stratigraphic sequence table; specifically, determine the vertical relationship between adjacent stratigraphic interfaces based on the stratigraphic sequence table, and check the relative positions of adjacent stratigraphic interfaces in the set of corrected stratigraphic interfaces in three-dimensional space; if the relative positions of adjacent stratigraphic interfaces contradict the vertical order in the stratigraphic sequence table, and the contradiction does not belong to the stratigraphic missing, stratigraphic duplicate, or stratigraphic inversion relationship marked in the stratigraphic sequence table, then it is determined that there is a sequence reversal that cannot be explained by the stratigraphic sequence table. Check whether there is a misconnection between the hanging wall and footwall at the corresponding stratigraphic interfaces on both sides of the fault. Specifically, determine the hanging wall and footwall truncation lines that are allowed to have geological correspondence based on the modified truncation line duality set. If there are hanging wall and footwall truncation lines in the 3D model that do not belong to the modified truncation line duality set and are used as closed boundaries or continuous surface boundaries of the same stratigraphic interface, then it is determined that there is a misconnection between the hanging wall and footwall. If the 3D model only displays the hanging wall and footwall truncation lines in the modified truncation line duality set as geological correspondences and does not geometrically weld them into the same continuous surface, then it is determined that there is no misconnection between the hanging wall and footwall. Check whether the geological body bounded by the initial fault plane and the modified stratigraphic interface set contains a false closed block caused by a truncation line with a risk of fault truncation duality; specifically, based on the geological body boundary formed by the initial fault plane and the modified stratigraphic interface set, determine whether the geological body boundary contains the truncation line connection relationship identified in S4 as having a risk of fault truncation duality; if it contains it, then a false closed block is determined to exist; if it does not contain it, then such a false closed block is determined not to exist. Simultaneously check whether the unconfirmed cut-off boundary set is forcibly closed; if the unconfirmed cut-off boundary is forcibly closed as part of the closed geological body boundary and there is no corresponding modified cut-off duality, then the location is determined to have failed the geological topological consistency check; if the unconfirmed cut-off boundary is retained as an uncertain boundary and does not participate in the forced closure, then the location does not constitute an erroneous closure. When all the above checks pass, a three-dimensional geological structure model is generated based on the initial fault plane set and the corrected stratigraphic interface set. The three-dimensional geological structure model includes fault planes, stratigraphic interfaces, and the spatial structure of geological bodies formed by the division of fault planes and stratigraphic interfaces. When any check fails, the position that failed the check is mapped to the set of pseudo-closed units to be corrected, and the process returns to S5 to reconstruct the stratigraphic interface of the fault neighborhood until the check passes or the corresponding position is retained as an unconfirmed truncation boundary.

[0040] When reconstructing from S5, first delete the candidate edges that caused the verification to fail, and then redetermine the dual relationship of the corrected cut-off line based on the remaining candidate edges. When the same pseudo-closed unit to be corrected no longer has candidate edges that simultaneously satisfy the sequence consistency constraint, the arrangement constraint along the fault strike constraint, and the fault displacement constraint after deleting the candidate edges that caused the verification to fail, the hanging wall cut-off line or footwall cut-off line involved in the pseudo-closed unit to be corrected is included in the unconfirmed cut-off line boundary set, and the pseudo-closed unit to be corrected is stopped from reconstructing from S5. The unconfirmed cut-off line boundary set is displayed as an uncertain boundary in the subsequent three-dimensional visualization results, and is not forcibly closed as a closed geological body boundary.

[0041] S7. Generate a three-dimensional visualization result based on the three-dimensional geological structure model, the set of pseudo-closed units to be corrected, the set of dual relations of corrected cut-off lines, and the set of unconfirmed cut-off line boundaries. In this step, a rotatable, cross-sectional, and queryable 3D geological structure visualization result is generated based on the 3D geological structure model. In this embodiment, the 3D visualization result refers to the rotatable, cross-sectional, and queryable 3D display result generated based on the 3D geological structure model. This 3D visualization result not only displays the geometric shape of fault planes and stratigraphic interfaces, but also displays the set of pseudo-closed units to be corrected, the set of corrected truncation line dual relationships, and the set of unconfirmed truncation line boundaries, so that users can distinguish the real geological correspondences, the pseudo-closed positions that have existed in the past, and the uncertain boundaries that cannot be reliably closed. The visualization results of three-dimensional geological structures show the set of dual relationships between fault planes, stratigraphic interfaces, hanging wall truncation lines, footwall truncation lines, and modified truncation lines in the three-dimensional geological structure model; such as Figure 4 As shown, the three-dimensional geological structure model is displayed in the form of a three-dimensional geological block. The model includes fault planes, stratigraphic interfaces, hanging wall, footwall, and truncation lines on both sides of the fault. The fault planes divide the three-dimensional geological block into the hanging wall and footwall. Multiple stratigraphic interfaces are truncated at the fault, forming hanging wall truncation lines 1, 2, and 3, and footwall truncation lines 1, 2, and 3, respectively. The figure uses double-headed arrows to indicate the modified truncation line pairings, which express the geological correspondence between the stratigraphic interfaces on both sides of the fault, but do not represent the connection between the hanging wall truncation lines and the footwall. The geometric welding of the truncation line is a continuous curved surface; the dashed boxes or dashed circles in the figure indicate the false closed units to be corrected, which are used to indicate the local false closed positions formed due to the mismatch of truncation lines during the original modeling process; the dashed lines or dotted lines indicate the unconfirmed truncation line boundaries, which are used to indicate the truncation line boundaries where the true dual relationship cannot be uniquely determined under the constraints of existing multi-source geological structural data; through the above visualization display method, users can distinguish the true geological correspondence, the false closed positions to be corrected and the uncertain boundaries while observing the three-dimensional geological structural model, thereby improving the interpretability of the three-dimensional geological structural model in the fault development area; Among them, "rotatable" means that users can observe the spatial relationship of fault planes, stratigraphic interfaces, and fault cut-off lines from different perspectives; "sectionable" means that users can view the dual relationship of stratigraphic interfaces, fault planes, and cut-off lines inside the 3D geological structure model according to a specified section plane; and "queryable" means that users can select fault planes, stratigraphic interfaces, hanging wall cut-off lines, or footwall cut-off lines, and view their respective faults, corresponding stratigraphic interfaces, sidewall attributes, and cut-off line dual relationships. In the 3D geological structure visualization results, a prompt is displayed for the set of false closed units to be corrected. The prompt includes the initial fault plane where the false closed unit to be corrected is located, the hanging wall truncation line where the order is out of order, the footwall truncation line corresponding to the error, and the corresponding stratigraphic interface. The purpose of the prompt is to enable users to identify the locations where incorrect closure relationships were formed during the original modeling process. The set of modified truncation line dual relationships is marked and displayed; the marking and display includes displaying the hanging wall truncation line and footwall truncation line that form the modified truncation line dual relationship, and marking their corresponding stratigraphic interfaces and the initial fault plane to which they belong; the set of modified truncation line dual relationships is used to illustrate the geological correspondence between the stratigraphic interfaces on both sides of the fault, and does not indicate that the two truncation lines are geometrically welded. Uncertain boundary display is performed on the set of unconfirmed tangent line boundaries. Uncertain boundary display includes displaying tangent lines whose duality cannot be determined as uncertain boundaries, so that users can identify that a reliable correspondence between the upper and lower plates has not yet been formed at this location, thereby avoiding mistaking uncertain boundaries for definite closed structural boundaries. This step outputs a 3D visualization result; this 3D visualization result can simultaneously express the geometric shape of the 3D geological structure model, the duality of the corrected cut-off line, the pseudo-closed units to be corrected, and the unconfirmed cut-off line boundaries.

[0042] Example 2: Based on Example 1, this example further illustrates the process of establishing a candidate dual diagram of a fault truncation line and identifying false closed units. Assume there is a first fault in the target area, which cuts through the first stratigraphic interface, the second stratigraphic interface, and the third stratigraphic interface. Based on borehole stratification data and geological profile data, the first stratigraphic interface, the second stratigraphic interface, and the third stratigraphic interface form the first hanging wall truncation line, the second hanging wall truncation line, and the third hanging wall truncation line on the hanging wall side of the first fault, respectively, and the first footwall truncation line, the second footwall truncation line, and the third footwall truncation line on the footwall side of the first fault, respectively. The first initial fault plane is generated based on the fault control line of the first fault, and the first hanging wall truncation line, the second hanging wall truncation line and the third hanging wall truncation line are included in the hanging wall truncation line set of the first initial fault plane, and the first footwall truncation line, the second footwall truncation line and the third footwall truncation line are included in the footwall truncation line set of the first initial fault plane. The sequence consistency relationship between the hanging wall and footwall truncation lines is determined based on the stratigraphic sequence table. When the first hanging wall truncation line and the first footwall truncation line correspond to the same first stratigraphic interface, they satisfy the sequence consistency constraint. When the second hanging wall truncation line and the second footwall truncation line correspond to the same second stratigraphic interface, they satisfy the sequence consistency constraint. When the third hanging wall truncation line and the third footwall truncation line correspond to the same third stratigraphic interface, they satisfy the sequence consistency constraint. Based on the strike direction of the first fault, all hanging wall and footwall truncation lines are sorted along the fault strike. If the first, second, and third hanging wall truncation lines are arranged in the order of first, second, and third on the hanging wall side, while the corresponding footwall truncation lines are arranged in the order of first, third, and second, then there is a risk of order reversal in the candidate relationships between the second hanging wall truncation line and the third footwall truncation line, and between the third hanging wall truncation line and the second footwall truncation line. Next, based on the fault attribute table, determine whether the above-mentioned order reversal can be explained by fault branching, fault properties, or fault displacement changes, and based on the stratigraphic sequence table, determine whether the order reversal can be explained by stratigraphic missing, stratigraphic repeat, or stratigraphic inversion relationship; if it cannot be explained by the fault attribute table and stratigraphic sequence table, then it is determined that there is a risk of fault truncation line dual misorder. Finally, an initial closed boundary is constructed based on the first initial fault plane, the stratigraphic profile, and the candidate dual diagram of the fault truncation line. If the initial closed boundary is formed by the second hanging wall truncation line and the third footwall truncation line, and the third hanging wall truncation line and the second footwall truncation line, and encloses a locally closed structural surface, then the locally closed structural surface is identified as a fault truncation line dual misorder type pseudo-closed unit. This pseudo-closed unit appears as a continuous stratigraphic interface in three-dimensional visualization, but its actual geological sequence has been mismatched. Therefore, it is necessary to remove the erroneous closed connection and redetermine the set of corrected truncation line dual relationships in subsequent steps.

[0043] Example 3, based on Example 1, further illustrates the process of reconstructing the stratigraphic interface in the fault neighborhood and generating the three-dimensional visualization results; After identifying the set of pseudo-closed units to be corrected, for each pseudo-closed unit to be corrected, its erroneous closure connections are removed. The removed erroneous closure connections no longer serve as continuous boundaries of the same stratigraphic interface, nor do they participate in the closure structure of the three-dimensional geological body. In the candidate dual diagram of fault truncation lines, the dual relationship of the modified truncation line is re-determined. During the re-determination, candidate edges that have been judged to have the risk of fault truncation line duality are no longer selected. Instead, candidate edges that satisfy the sequence consistency constraint, the arrangement constraint along the fault strike constraint, and the fault displacement constraint are selected. If a truncation line does not have a candidate edge that meets the above constraints, the truncation line is not forced to close. Instead, it enters the unconfirmed truncation line boundary set. When reconstructing stratigraphic interfaces in the vicinity of a fault, the initial fault plane is used as the termination boundary of the stratigraphic interface. For stratigraphic interfaces located on the hanging wall side of the initial fault plane, reconstruction is performed based on the borehole locations and stratigraphic profiles on the hanging wall side. For stratigraphic interfaces located on the footwall side of the initial fault plane, reconstruction is performed based on the borehole locations and stratigraphic profiles on the footwall side. The geological correspondence between the stratigraphic interfaces reconstructed on the hanging wall side and the stratigraphic interfaces reconstructed on the footwall side is expressed through a set of modified truncation line duality relationships, but they are not directly geometrically welded together. After reconstruction, a geological topological consistency check is performed. If it is found that the same stratigraphic interface still directly connects across the initial fault plane, or if it is found that there are erroneous connections between the hanging wall and footwall on both sides of the fault that are not included in the set of corrected truncation line duality, the reconstruction step is returned for reprocessing. If it is found that an unconfirmed truncation line boundary is forcibly closed, the forced closure is canceled and it is retained as an unconfirmed truncation line boundary. Once the verification is successful, a three-dimensional geological structure model is generated, and a three-dimensional visualization result is generated based on this model. The three-dimensional visualization result displays the fault plane, stratigraphic interface, hanging wall truncation line, and footwall truncation line in the three-dimensional geological structure model. It also displays the set of corrected truncation line dual relations, which is used to represent the true correspondence between the stratigraphic interfaces on both sides of the fault; it displays the set of false closure units to be corrected, which is used to indicate the location of false closures with over-dual misordered order in the original model; and it displays the set of unconfirmed truncation line boundaries, which is used to indicate the boundaries where the dual relations of truncation lines cannot be reliably established.

[0044] For truncation lines whose true duality can be determined based on fault attribute tables, stratigraphic sequence tables, and fault displacement variation information, this invention generates a set of corrected truncation line dualities. For truncation lines whose true duality cannot be uniquely determined, this invention does not force closure but retains them as a set of unconfirmed truncation line boundaries. This avoids false closures due to insufficient data or multiple solutions, resulting in new fault truncation line duality misordering. Therefore, this invention avoids incorrectly connecting truncation lines that do not belong to the same stratigraphic interface or do not satisfy fault displacement relationships, reducing the risk of surface closure but distorted geological relationships in 3D models, and improving the interpretability and visualization reliability of 3D geological structural models in fault-developed areas.

[0045] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for three-dimensional modeling and visualization of geological structures, characterized in that, Includes the following steps: S1 acquires multi-source geological structure data of the target area, unifies the spatial benchmark, and generates a set of borehole site locations, a set of profile stratigraphic lines, a set of fault control lines, a fault attribute table, and a stratigraphic sequence table. S2 generates an initial fault plane set based on the fault control line set, and extracts the hanging wall truncation line set and the footwall truncation line set on both sides of the initial fault plane; S3 establishes a candidate dual diagram of fault truncation lines based on the fault attribute table, stratigraphic sequence table, hanging wall truncation line set, and footwall truncation line set; S4 identifies fault truncation line dual misordered pseudo-closed units based on the fault truncation line candidate dual diagram, fault attribute table and stratigraphic sequence table, and generates a set of pseudo-closed units to be corrected. S5 removes erroneous closed connections based on the set of pseudo-closed units to be corrected and the candidate dual diagram of fault truncation lines. It then reconstructs the stratigraphic interfaces in the fault neighborhood by combining the set of borehole site locations, the set of profile stratigraphic lines, the stratigraphic sequence list, and the set of initial fault planes. This generates a set of corrected truncation line dual relationships, a set of corrected stratigraphic interfaces, and a set of unconfirmed truncation line boundaries. S6 performs geological topological consistency verification based on the initial fault plane set, the corrected stratigraphic interface set, and the unconfirmed truncation line boundary set, and generates a three-dimensional geological structure model. S7 generates 3D visualization results based on the 3D geological structure model, the set of pseudo-closed units to be corrected, the set of corrected cut-off line duality relations, and the set of unconfirmed cut-off line boundaries.

2. The method for three-dimensional modeling and visualization of geological structures according to claim 1, characterized in that, In S1, the multi-source geological structural data includes borehole stratification data, geological profile data, surface geological map data, geophysical interpretation line data, and fault interpretation data. The borehole stratification data includes borehole coordinates, borehole depth, stratigraphic number, and stratum boundary depth. The geological profile data includes profile location, profile direction, stratigraphic boundaries within the profile, and fault lines. The fault interpretation data includes fault name, fault strike, dip, dip angle, fault nature, fault control points, and fault control lines. The fault attribute table is generated based on the fault interpretation data and includes fault nature and fault displacement variation information determined by the geological profile data. The fault control line set is generated based on fault control points and fault control lines. The stratigraphic sequence table is established based on the stratigraphic order and the stratigraphic missing, repeated, or inverted relationships marked by the geological profile data.

3. The method for three-dimensional modeling and visualization of geological structures according to claim 1, characterized in that, In S2, an initial fault plane set is generated based on the fault control line set, including: Initial fault planes are generated using triangular mesh surface fitting, spline surface fitting, or implicit surface fitting. The stratigraphic interface constraint location is determined based on the stratigraphic profile set and the borehole site set. The intersection location between the stratigraphic interface constraint location and the initial fault plane is identified and the fault cut-off line is extracted. The wall-side attributes of each fault cut-off line are determined based on the normal vector of the initial fault plane and the spatial relationship between the points on both sides of the fault. The wall-side attributes are either the hanging wall or the footwall. Based on the side properties, a set of upper plate cutting lines and a set of lower plate cutting lines are formed.

4. The method for three-dimensional modeling and visualization of geological structures according to claim 1, characterized in that, In S3, candidate dual diagrams for fault truncation lines are established, including: Within the same initial fault plane, the hanging wall tangent is used as the first type of node and the hanging wall tangent as the second type of node. Candidate edges are established between the hanging wall tangent and the hanging wall tangent that meet the candidate pairing conditions to obtain the candidate dual diagram of the fault tangent. The candidate pairing conditions include sequence consistency constraints, arrangement constraints along the fault strike, and fault displacement constraints.

5. The method for three-dimensional modeling and visualization of geological structures according to claim 4, characterized in that, The sequence consistency constraint requires that the hanging wall and footwall truncation lines connected by the candidate edges correspond to the same stratigraphic interface, or satisfy the stratigraphic relationships allowed in the stratigraphic sequence table, such as missing, repeated, or inverted stratigraphic relationships; the fault strike alignment constraint requires that the projection positions of the hanging wall and footwall truncation lines connected by the candidate edges on the initial fault plane be consistent with the stratigraphic arrangement order in the adjacent geological profile; the fault displacement constraint requires that the relative positions between the hanging wall and footwall truncation lines connected by the candidate edges satisfy the fault properties and fault displacement variation information in the fault attribute table.

6. The method for three-dimensional modeling and visualization of geological structures according to claim 1, characterized in that, In S4, the dual-disorder type false closure units of the fault truncation line are identified, including: In the candidate dual diagram of fault truncation lines, the hanging wall truncation lines and footwall truncation lines are sorted along the fault strike respectively; When the hanging wall truncation lines are adjacent in the sorting, but the corresponding footwall truncation lines of their candidates show order reversal, cross-layer connection or non-adjacent jump connection, and cannot be explained by the fault attribute table and stratigraphic sequence table, it is determined that there is a risk of fault truncation line dual misorder. An initial closed boundary is constructed based on the initial fault plane set, the profile stratigraphic line set, and the candidate dual diagram of fault cut-off lines. When the initial closed boundary is formed by connecting cut-off lines with the risk of fault cut-off line dual misorder, the corresponding region is determined as a false closed unit of fault cut-off line dual misorder.

7. The method for three-dimensional modeling and visualization of geological structures according to claim 1, characterized in that, In S4, each false closure unit to be corrected in the set of false closure units to be corrected includes the upper hanging wall truncation line that is out of order, the lower hanging wall truncation line that is incorrectly corresponding to the upper hanging wall truncation line, the initial fault plane to which the false closure unit to be corrected belongs, and the stratigraphic interface corresponding to the false closure unit to be corrected.

8. The method for three-dimensional modeling and visualization of geological structures according to claim 1, characterized in that, In S5, the stratigraphic boundaries of the fault neighborhood are reconstructed, including: The closed connection formed between the upper truncation line and the lower truncation line corresponding to the error in the set of corrected false closed elements is removed; Based on the candidate dual diagram of fault cut-off lines, the dual relationships of cut-off lines that satisfy sequence consistency constraints, fault strike arrangement constraints, and fault displacement constraints are re-determined, and a set of modified cut-off line dual relationships is generated. The same stratigraphic interface terminates at the initial fault plane at the fault, and the geological duality between the hanging wall truncation line and the footwall truncation line is preserved without geometric welding. A modified stratigraphic interface set is generated based on the borehole site set, the profile stratigraphic line set, the stratigraphic sequence list and the initial fault plane set. For cut lines whose duality cannot be determined, generate a set of unconfirmed cut line boundaries.

9. The method for three-dimensional modeling and visualization of geological structures according to claim 1, characterized in that, In S6, geological topological consistency verification is performed, including: Check whether the same stratigraphic interface incorrectly crosses the initial fault plane at the fault location; Check for sequence inversions between adjacent stratigraphic interfaces that cannot be explained by the stratigraphic sequence table; Check whether there is any misconnection between the hanging wall and footwall at the corresponding stratigraphic interfaces on both sides of the fault. Examine whether the geological body enclosed by the initial fault plane and the modified stratigraphic interface set contains a false closed block caused by a truncation line with a risk of dual misorder of fault truncation lines; When the verification fails, the location of the failed verification is mapped to the set of pseudo-closed units to be corrected, and the stratigraphic interface of the fault neighborhood is reconstructed.

10. The method for three-dimensional modeling and visualization of geological structures according to claim 1, characterized in that, In S7, 3D visualization results are generated, including: Generate rotatable, cross-sectional, and queryable 3D geological structure visualization results based on the 3D geological structure model; The visualization results of the three-dimensional geological structure show the set of dual relationships of fault planes, stratigraphic interfaces, hanging wall truncation lines, footwall truncation lines, and modified truncation lines in the three-dimensional geological structure model. The system displays prompts for sets of pseudo-closed elements to be corrected, identifies sets of dual relations of corrected tangent lines, and displays uncertain boundaries for sets of unconfirmed tangent line boundaries.

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