Deposit paleoflow direction analysis method based on digital outcrop live-action three-dimensional model

Abstract

The invention discloses a sedimentary paleoflow direction analysis method based on a digital outcrop live-action three-dimensional model, belongs to the technical field of geological exploration and development, effectively combines unmanned aerial vehicle live-action shooting and three-dimensional live-action modeling through an oblique photography technology, and establishes an accurate and complete digital outcrop live-action three-dimensional model. According to the method, the working efficiency of the paleo-flow direction analysis work is improved, the labor cost is saved, the effective sedimentary paleo-flow direction indication structure is quickly and accurately recognized through recognition and validity verification of the sedimentary paleo-flow direction indication structure, the workload of paleo-flow direction analysis is reduced, paleo-flow direction data of a previous sedimentary layer is corrected and restored through occurrence correction, and the accuracy of paleo-flow direction analysis is improved. The accuracy of a paleoflow direction analysis result is improved, finally, the paleoflow direction analysis result is visually displayed in a paleoflow direction rose diagram form, and integrated analysis of deposition paleoflow direction data acquisition, processing, correction, resolving and visualization is achieved.

Description

Technical Field

[0001] This invention belongs to the field of geological exploration and development technology, specifically involving a method for analyzing sedimentary paleocurrent direction based on a digital outcrop real-scene 3D model. Background Technology

[0002] Paleocurrent analysis plays a crucial role in sedimentary petrology and paleogeographic reconstruction. It helps identify sediment sources, infer the dip of paleoslopes, predict the orientation of paleocoastlines, and determine the location and orientation of sedimentary basin boundaries. Traditional paleocurrent analysis methods primarily consist of two stages: field data acquisition and laboratory data processing. Due to the complexity and diversity of geological conditions, field measurements often face high safety risks and are extremely difficult. Furthermore, acquiring paleocurrent data is a demanding task; to ensure statistical significance, a large amount of data must be obtained, placing high demands on fieldworkers. In the laboratory data processing stage, the acquired paleocurrent data is typically presented in two-dimensional tables, text, and photographs, limiting the data's three-dimensional spatial representation capabilities. This fails to intuitively demonstrate the spatial relationship between the data and actual geological structures when interpreting geological phenomena, reducing the data's interpretability and intuitiveness.

[0003] In the field, geologists use compasses to directly measure the attitude of rock strata. This process is simple and direct but usually time-consuming and easily limited by natural conditions such as terrain. Furthermore, in indoor processing of paleocurrent data, due to the large volume of data, traditional spherical rotation principles and methods for correcting paleocurrent data to their original sedimentary state often require a significant amount of time and are inefficient. In the 20th century, methods for processing paleocurrent data evolved from manual correction using stereographic projection principles to computer-based correction. Commonly used correction software such as StereoNett and the open-source Innstereo can perform the correction work. However, while previous studies have achieved a high degree of digitization in processing paleocurrent data, they lack an integrated method that combines UAV aerial photography and 3D modeling, and utilizes 3D modeling for sedimentary paleocurrent analysis.

[0004] As mentioned above, how to provide a sedimentary paleocurrent analysis method based on a digital outcrop real-scene 3D model that combines drone real-scene photography and 3D real-scene modeling to achieve integrated sedimentary paleocurrent analysis has become an urgent problem to be solved. Summary of the Invention

[0005] The purpose of this invention is to provide a method for analyzing sedimentary paleocurrent direction based on a three-dimensional model of a digital outcrop, in order to solve the aforementioned problems existing in the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a method for analyzing sedimentary paleocurrent direction based on a three-dimensional model of a digital outcrop, including:

[0008] The three-dimensional coordinates of the control points of the outcrop and the original multi-angle oblique photographic outcrop texture image are obtained. The original multi-angle oblique photographic outcrop texture image is preprocessed to obtain a multi-angle oblique photographic outcrop texture image. The coordinates of the control points of the outcrop are used to perform multi-view image processing to construct a triangular network model. The multi-angle oblique photographic outcrop texture image is texture mapped on the triangular network model to generate a digital outcrop real-scene three-dimensional model.

[0009] Based on the digital outcrop real-world 3D model, multiple candidate sedimentary paleocurrent direction indicator structures were identified, and the validity of each candidate sedimentary paleocurrent direction indicator structure was verified using virtual auxiliary lines, so that the verified candidate sedimentary paleocurrent direction indicator structures were taken as valid sedimentary paleocurrent direction indicator structures.

[0010] For each of the effective sedimentary paleocurrent direction indicator structures, the geometric morphology and exposure integrity of the structural surface are determined to obtain Class I and Class II structural surfaces. The Class I structural surface is used to represent effective sedimentary paleocurrent direction indicator structures with a planar geometric morphology and complete exposure of the structural surface. The Class II structural surface is used to represent effective sedimentary paleocurrent direction indicator structures with a vertical geometric morphology, a curved geometric morphology, or incomplete exposure of the structural surface.

[0011] For each type of structural surface, a three-point method is used to determine a type of structural auxiliary plane in the digital outcrop real-world 3D model. The dip direction, dip angle, and normal vector of the type of structural surface are calculated using the type of structural auxiliary plane to obtain the occurrence of an effective sedimentary structural surface.

[0012] For each type II structural surface, the pre-accretionary laminae in each type II structural surface are identified in the digital outcrop real-world 3D model, and the type II structural auxiliary plane is determined based on the pre-accretionary laminae. The dip direction, dip angle and normal vector of the type II structural surface are calculated using the type II structural auxiliary plane to obtain the occurrence of the type II effective sedimentary structural plane.

[0013] Obtain the stratigraphic strike vector, and perform attitude correction on the attitude of each of the first-class effective sedimentary structure planes and each of the second-class effective sedimentary structure planes based on the stratigraphic strike vector to obtain the corrected attitude data;

[0014] Based on the corrected occurrence data, a paleocurrent direction analysis is performed to obtain the paleocurrent direction analysis results, which are then visualized. The paleocurrent direction analysis results include a paleocurrent direction rose diagram.

[0015] In one possible design, the three-dimensional coordinates of the outcrop ground control points and the original multi-angle oblique photographic image of the outcrop texture are obtained, including:

[0016] Geological target information is acquired, and a UAV flight plan is generated based on the geological target information, wherein the geological target information includes paleocurrent analysis requirements, target outcrop locations, and geomorphological information;

[0017] Based on the geological target information, ground control points are set up at the outcrop location to obtain the three-dimensional coordinates of the outcrop ground control points;

[0018] Based on the aforementioned UAV flight scheme, the UAV shooting module is configured and the UAV flight path is planned. According to the UAV flight path plan, multi-angle oblique photography of the target outcrop is performed to obtain the original multi-angle oblique photography outcrop texture image.

[0019] Accordingly, the original multi-angle oblique photographic outcrop texture image is preprocessed to obtain a multi-angle oblique photographic outcrop texture image, and multi-view image processing is performed using the coordinates of the outcrop ground control points to construct a triangular network model. The multi-angle oblique photographic outcrop texture image is then texture-mapped onto the triangular network model to generate a digital outcrop real-world 3D model, which includes:

[0020] Lens distortion correction is performed on the original multi-angle oblique photography outcrop texture image collected by the UAV to obtain a distortion-free multi-angle oblique photography outcrop texture image. The UAV pose data recorded by the UAV positioning and attitude determination system is also obtained to bind the UAV pose data and the distortion-free multi-angle oblique photography outcrop texture image to form a pre-multi-angle oblique photography outcrop texture image.

[0021] A preset aerial triangulation error threshold is obtained, and the coordinates of the outcrop ground control points are used to perform multi-view joint adjustment processing on the pre-multi-angle oblique photography outcrop texture image to optimize the aerial triangulation measurement error of the multi-angle oblique photography outcrop texture image to be lower than the preset aerial triangulation error threshold, so as to obtain the multi-angle oblique photography outcrop texture image.

[0022] Using the structure-of-motion algorithm, multiple feature points are extracted from the multi-angle oblique photography outcrop texture image. Feature matching is performed on each feature point to generate a multi-view sparse point cloud and a multi-view depth map from the multi-angle oblique photography outcrop texture image. The multi-view depth map and the multi-view sparse point cloud are then fused to obtain a multi-view dense point cloud.

[0023] The Delaunay triangulation algorithm is used to segment the multi-view dense point cloud into multiple non-overlapping sets of triangles to construct an irregular triangular network model.

[0024] The multi-angle oblique photographic outcrop texture image is projected onto the surface of the triangular network model, and the seams between the various mapped images on the surface of the triangular network model are eliminated to obtain an initial digital outcrop real-scene 3D model.

[0025] In the real-world image formed by the initial digital outcrop real-world 3D model, the mesh holes caused by vegetation occlusion are repaired, and the mesh is simplified to obtain the digital outcrop real-world 3D model.

[0026] In one possible design, based on the digital outcrop real-world 3D model, multiple candidate sedimentary paleocurrent indication structures are identified, including:

[0027] Multi-angle real-scene images are captured from the digital outcrop's 3D model. Based on these images, different sedimentary cross-bedding structures are identified, including platy cross-bedding, wedge-shaped cross-bedding, and trough-shaped cross-bedding.

[0028] In the aforementioned platy cross-bedding structure, the parallel interfaces between the single layers of the platy cross-bedding and the pre-accretionary laminations with consistent dips are identified in detail to obtain the first sedimentary structural features.

[0029] In the wedge-shaped cross-bedding structure, the non-parallel cutting relationship between the layers of the wedge-shaped cross-bedding and the oblique cross-bedding features of the laminations and interfaces are identified in detail to obtain the second sedimentary structure features.

[0030] In the trough-shaped cross-bedding structure, the scouring morphology of the trough-shaped bottom interface of the transverse section of the trough-shaped cross-bedding is identified in detail, the relationship between the arc-shaped bottom boundary and the oblique intersecting lamination of the longitudinal section of the trough-shaped cross-bedding is identified in detail, and the petal-shaped overlapping structure of the top view of the trough-shaped cross-bedding is identified in detail, so as to obtain the third sedimentary structure characteristics.

[0031] Obtain preset sedimentary paleocurrent direction indicator markers, and compare the identified first sedimentary structural features, second sedimentary structural features, and third sedimentary structural features with the sedimentary paleocurrent direction indicator markers respectively, so as to select candidate sedimentary paleocurrent direction indicator structures from the digital outcrop real-world 3D model;

[0032] Accordingly, for each candidate paleocurrent direction indicator structure, the validity is verified using virtual auxiliary lines. The verified candidate paleocurrent direction indicator structures are then considered valid paleocurrent direction indicator structures, including:

[0033] Based on the sedimentary cross-bedding structure type corresponding to each of the candidate sedimentary paleocurrent direction indicator structures, virtual auxiliary lines are drawn in the candidate sedimentary paleocurrent direction indicator structures of different sedimentary cross-bedding structure types;

[0034] Based on the consistency of the virtual auxiliary lines, the candidate sedimentary paleocurrent direction indicator structures are validated for effectiveness, and the candidate sedimentary paleocurrent direction indicator structures that pass the validity validation are designated as valid sedimentary paleocurrent direction indicator structures.

[0035] In one possible design, the geometry and exposure integrity of each of the effective paleocurrent indicator structures are determined to obtain Class I and Class II structural surfaces, including:

[0036] Based on the real-scene image of the surface of the digital outcrop real-scene 3D model, the geometric shape of each effective sedimentary paleocurrent direction indicator structure is determined. The effective sedimentary paleocurrent direction indicator structures with the determination result of planar structure are regarded as pre-classified structure surfaces, and the effective sedimentary paleocurrent direction indicator structures with the determination result of vertical structure are regarded as class II structure surfaces.

[0037] Based on the real-world image of the surface of the digital outcrop real-world 3D model, the exposure integrity of each of the pre-class I structural surfaces is determined. The pre-class I structural surfaces with complete exposure are classified as Class I structural surfaces, and the pre-class I structural surfaces with incomplete exposure are classified as Class II structural surfaces. In the Class I structural surfaces, the pre-accumulated texture layer is located on the plane where the surface of the Class I structural surface is located and is parallel to the plane where the surface of the Class II structural surface is located. In the Class II structural surfaces, the pre-accumulated texture layer is located inside the Class II structural surface and intersects with the plane where the surface of the Class II structural surface is located.

[0038] In one possible design, for each type of structural surface, a three-point method is used to determine a structural auxiliary plane in the digital outcrop realistic 3D model. The dip direction, dip angle, and normal vector of the structural surface are then calculated using these auxiliary planes to obtain the attitude of an effective sedimentary structural surface, including:

[0039] Based on the digital outcrop real-world 3D model, three non-collinear points are selected on the first type of structural surface, and the global Cartesian coordinates of the three non-collinear points are obtained. A first type of structural auxiliary plane is fitted through these three non-collinear points, wherein the first type of structural auxiliary plane is parallel to the plane on which the first type of structural surface is located.

[0040] Based on the aforementioned auxiliary construction plane, a class of auxiliary construction plane equations are constructed, and a class of construction surface normal vectors are calculated based on the aforementioned auxiliary construction plane equations.

[0041] Based on the equation of the first type of auxiliary plane and the normal vector of the first type of structural surface, the dip direction and dip angle of the first type of structural surface are calculated.

[0042] The dip direction, dip angle, and normal vector of a type of structural surface are integrated to form an effective sedimentary structural plane occurrence.

[0043] In one possible design, for each type II structural surface, pre-accretionary laminae are identified in the digital outcrop real-world 3D model. Based on these pre-accretionary laminae, auxiliary planes for the type II structures are determined. The dip direction, dip angle, and normal vector of the type II structural surface are then calculated using these auxiliary planes to obtain the attitude of the effective type II sedimentary structural plane, including:

[0044] Based on the digital outcrop real-world 3D model, the pre-aggregate striations on the second type of structural surface are identified to obtain the pre-aggregate striation direction;

[0045] On the type II structural surface, two points are selected along the direction of the pre-accumulation layer, and one point on the type II structural surface that is not in the direction of the pre-accumulation layer is selected.

[0046] Obtain the global Cartesian coordinates of two points along the direction of the pre-integral texture layer and a point not along the direction of the pre-integral texture layer, and fit a pre-type II construction auxiliary plane through these three points, wherein the pre-type II construction auxiliary plane is perpendicular to the plane where the pre-integral texture layer is located;

[0047] Based on the pre-class II construction auxiliary plane, the equation of the pre-class II construction auxiliary plane is constructed, and the normal vector of the pre-class II construction surface is calculated according to the equation of the pre-class II construction auxiliary plane;

[0048] Based on the pre-type II construction auxiliary plane and the normal vector of the pre-type II construction surface, a type II construction auxiliary plane perpendicular to the pre-type II construction auxiliary plane is constructed, wherein the type II construction auxiliary plane is parallel to the plane where the pre-integral texture layer is located;

[0049] Based on the two types of auxiliary construction planes, the equations of the two types of auxiliary construction planes are constructed, and the normal vectors of the two types of construction surfaces are calculated according to the two types of auxiliary construction planes;

[0050] Based on the equation of the second type of auxiliary plane and the normal vector of the second type of structural surface, the dip direction and dip angle of the second type of structural surface are calculated.

[0051] The dip direction, dip angle, and normal vector of the two types of structural surfaces are integrated to form the occurrence of the two types of effective sedimentary structural planes.

[0052] In one possible design, prior to obtaining the strike vector of the formation, the following is also included:

[0053] Using linear interpolation, multiple equidistant interpolation points are generated between any two edge points of the pre-aggregate texture on each of the first type of structural surfaces, and multiple equidistant interpolation points are generated between two edge points in the direction of the pre-aggregate texture on each of the second type of structural surfaces.

[0054] For each interpolation point, the intersection point between the interpolation point and the first-type or second-type structural surface is calculated to obtain multiple intersection points;

[0055] On each of the first-type and second-type structural surfaces, the distances between adjacent intersection points are calculated sequentially and summed to obtain the real-world distance measurement results of the pre-accretionary texture layers on each of the first-type and second-type structural surfaces.

[0056] In one possible design, obtaining the formation strike vector includes:

[0057] Based on the digital outcrop real-world 3D model, the stratigraphic planes of the first type of structural surface and the second type of structural surface are projected and determined;

[0058] For the stratigraphic planes of the first type of structural surface and the second type of structural surface, stratigraphic plane equations are constructed, and stratigraphic plane normal vectors are calculated based on the stratigraphic plane equations.

[0059] The dip direction and dip angle of the stratigraphic plane are calculated based on the stratigraphic plane equation and the stratigraphic plane normal vector.

[0060] Based on the dip direction of the stratigraphic plane, the dip direction of the stratigraphic plane, the normal vector of the stratigraphic plane, the attitude of the first type of effective sedimentary structure plane, and the attitude of the second type of effective sedimentary structure plane, the stratigraphic strike vector is calculated;

[0061] Accordingly, based on the stratigraphic strike vector, the attitude of each of the first-class effective sedimentary structural planes and the attitude of each of the second-class effective sedimentary structural planes are corrected to obtain corrected attitude data, which includes:

[0062] A three-dimensional calibration coordinate system is defined with the starting point of the strike vector of the strata as the origin, the strike vector of the strata as the Y-axis, and the direction of the normal vector of the strata plane as the Z-axis.

[0063] Place the normal vector of the first type of construction surface in the three-dimensional correction coordinate system, and determine whether the normal vector of the first type of construction surface is perpendicular to the Y-axis of the three-dimensional correction coordinate system;

[0064] If so, the dip direction, dip angle, and normal vector of the first type of structural surface are integrated to form the corrected effective sedimentary structural plane orientation.

[0065] If not, the normal vector of the first type of structural surface is corrected to a vector perpendicular to the Y-axis of the three-dimensional correction coordinate system to form a corrected normal vector of the first type of structural surface. Based on the corrected normal vector of the first type of structural surface, the dip direction and dip angle of the corrected first type of structural surface are calculated. The dip direction, dip angle, and normal vector of the corrected first type of structural surface are then integrated to form the orientation of the corrected effective sedimentary structural plane.

[0066] The normal vectors of the two types of construction surfaces are placed in the three-dimensional correction coordinate system, and the normal vectors of the two types of construction surfaces are rotated around the Y-axis of the three-dimensional correction coordinate system to form a normal vector cone, with the origin of the three-dimensional correction coordinate system as the starting point.

[0067] Based on the normal vector cone, the normal vectors of the two types of structural surfaces are corrected to obtain the corrected normal vectors of the two types of structural surfaces.

[0068] Based on the corrected type II structural surface normal vectors, the corrected type II structural surface dip and dip angle are calculated, and the corrected type II structural surface dip, dip angle and normal vectors are integrated to form the corrected type II effective sedimentary structural plane orientation.

[0069] The corrected type I effective sedimentary structure plane occurrences and the corrected type II effective sedimentary structure plane occurrences are integrated to form corrected occurrence data.

[0070] In one possible design, based on the corrected attitude data, a paleocurrent analysis is performed to obtain the paleocurrent analysis results, and these results are then visualized, including:

[0071] Outlier cleaning is performed on the corrected structural surface dip data and corrected structural surface dip angle data in the corrected attitude data. The corrected structural surface dip data includes corrected type I structural surface dip and corrected type II structural surface dip, and the corrected structural surface dip angle data includes corrected type I structural surface dip and corrected type II structural surface dip.

[0072] A blank rose diagram is created, and the 360° orientation circle in the blank rose diagram is divided into 36 angle intervals. For each angle interval, the frequency of the data points generated by the corrected attitude data after outlier cleaning falling into each angle interval is counted.

[0073] Based on the frequency of data points falling into the corrected attitude data in each angle interval, rose petals of the corresponding angle interval are drawn in the blank rose diagram to form an ancient flow direction rose diagram. The angle interval with the longest rose petal in the ancient flow direction rose diagram is taken as the ancient flow direction analysis result, and the ancient flow direction analysis result is used to represent the dominant direction of ancient water flow.

[0074] The paleocurrent rose diagram is used as the result of the sedimentary paleocurrent analysis and is visualized.

[0075] In one possible design, after visualizing the results of the paleocurrent analysis, the following is also included:

[0076] Based on the corrected occurrence data and the paleocurrent rose diagram, the paleocurrent analysis results are marked in the real-world images of each outcrop in the digital outcrop real-world 3D model.

[0077] The actual distance calculation results of the pre-accretionary striations of each of the first-type structural surfaces and each of the second-type structural surfaces are respectively marked on each of the first-type structural surfaces and each of the second-type structural surfaces in the digital outcrop real-scene 3D model to form a paleocurrent analysis model.

[0078] The ancient flow direction analysis model is stored and then visualized.

[0079] In a second aspect, the present invention provides an electronic device comprising a memory, a processor, and a transceiver connected in sequence and communication, wherein the memory is used to store a computer program, the transceiver is used to send and receive messages, and the processor is used to read the computer program and execute the sedimentary paleocurrent analysis method based on a digital outcrop real-world three-dimensional model as described in the first aspect or any possible design of the first aspect.

[0080] Thirdly, the present invention provides a computer-readable storage medium storing instructions that, when executed on a computer, perform the sedimentary paleocurrent analysis method based on a digital outcrop real-world three-dimensional model as described in the first aspect or any possible design of the first aspect.

[0081] Fourthly, the present invention provides a computer program product containing instructions that, when executed on a computer, cause the computer to perform the sedimentary paleocurrent analysis method based on a digital outcrop real-world three-dimensional model as described in the first aspect or any possible design of the first aspect.

[0082] Beneficial Effects: This invention provides a sedimentary paleocurrent direction analysis method based on a digital outcrop real-scene 3D model. By using oblique photogrammetry, it effectively combines UAV real-scene photography with 3D real-scene modeling to establish an accurate and complete digital outcrop real-scene 3D model, thereby improving the efficiency of paleocurrent direction analysis and saving labor costs. By identifying and validating sedimentary paleocurrent direction indicator structures, it can quickly and accurately identify effective sedimentary paleocurrent direction indicator structures, reducing the workload of paleocurrent direction analysis. Furthermore, by correcting and restoring the paleocurrent direction data of the pre-sedimentary layer through occurrence correction, it improves the accuracy of the paleocurrent direction analysis results. Finally, it visualizes the paleocurrent direction analysis results in the form of a paleocurrent direction rose diagram, realizing an integrated analysis of sedimentary paleocurrent direction data acquisition, processing, correction, calculation, and visualization. Attached Figure Description

[0083] Figure 1 This is a flowchart illustrating the sedimentary paleocurrent analysis method based on a digital outcrop real-world 3D model provided in an embodiment of the present invention.

[0084] Figure 2 This is a schematic diagram of various stratification structures in the digital outcrop real-world 3D model provided in an embodiment of the present invention;

[0085] Figure 3 A schematic diagram illustrating the three-point method processing principle of an effective sedimentary structure planar occurrence calculation method provided in an embodiment of the present invention;

[0086] Figure 4 This is a schematic diagram illustrating the auxiliary plane processing principle of the two types of effective sedimentary structure plane occurrence calculation method provided in the embodiments of the present invention;

[0087] Figure 5 A comparative diagram of spatial distance and real-world distance calculations provided in an embodiment of the present invention;

[0088] Figure 6 A schematic diagram illustrating the geometric processing principle of the attitude correction calculation method provided in an embodiment of the present invention;

[0089] Figure 7 This is a schematic diagram illustrating the paleocurrent analysis results and rose diagram provided in an embodiment of the present invention.

[0090] Figure 8 A schematic diagram illustrating the paleocurrent analysis results and paleocurrent annotations provided in this embodiment of the invention;

[0091] Figure 9 A schematic diagram illustrating the regional paleocurrent analysis results provided in an embodiment of the present invention;

[0092] Figure 10 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0093] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the present invention will be briefly introduced below in conjunction with the accompanying drawings and descriptions of the embodiments or the prior art. Obviously, the following description of the structure of the accompanying drawings is only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. It should be noted that the description of these embodiments is for the purpose of helping to understand the present invention, but does not constitute a limitation of the present invention.

[0094] It should be understood that although the terms first, second, etc., may be used herein to describe various units, these units should not be limited by these terms. These terms are only used to distinguish one unit from another. For example, a first unit may be referred to as a second unit, and similarly, a second unit may be referred to as a first unit, without departing from the scope of the exemplary embodiments of the invention.

[0095] It should be understood that the term "and / or" that may appear in this document is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, B exists alone, and A and B exist simultaneously. The term " / and" that may appear in this document describes another relationship between related objects, indicating that two relationships can exist. For example, A / and B can mean: A exists alone, and A and B exist alone. In addition, the character " / " that may appear in this document generally indicates that the related objects before and after it are in an "or" relationship.

[0096] Example:

[0097] like Figure 1 As shown, the first aspect of this embodiment provides a method for analyzing sedimentary paleocurrent direction based on a digital outcrop real-world 3D model, which may include, but is not limited to, the following steps:

[0098] S1. Obtain the three-dimensional coordinates of the control points of the outcrop and the original multi-angle oblique photography outcrop texture image. Preprocess the original multi-angle oblique photography outcrop texture image to obtain a multi-angle oblique photography outcrop texture image. Use the coordinates of the control points of the outcrop to perform multi-view image processing to construct a triangular network model. Map the multi-angle oblique photography outcrop texture image onto the triangular network model to generate a digital outcrop real-scene three-dimensional model.

[0099] In one possible implementation, step S1, acquiring the three-dimensional coordinates of the outcrop ground control points and the original multi-angle oblique photographic outcrop texture image, can be, but is not limited to, decomposed into the following steps S11-S13, including:

[0100] S11. Obtain geological target information and generate a UAV flight plan based on the geological target information, wherein the geological target information includes paleocurrent analysis requirements, target outcrop locations, and geomorphological information;

[0101] S12. Based on the geological target information, ground control points are set up at the outcrop location to obtain the three-dimensional coordinates of the outcrop ground control points;

[0102] S13. Based on the UAV flight scheme, configure the UAV shooting module and plan the UAV flight path. According to the UAV flight path plan, perform multi-angle oblique photography of the target outcrop to obtain the original multi-angle oblique photography outcrop texture image.

[0103] Accordingly, in step S1, the original multi-angle oblique photographic outcrop texture image is preprocessed to obtain a multi-angle oblique photographic outcrop texture image, and multi-view image processing is performed using the coordinates of the outcrop ground control points to construct a triangular network model. The multi-angle oblique photographic outcrop texture image is then texture-mapped onto the triangular network model to generate a digital outcrop real-world 3D model. This can be decomposed into, but is not limited to, the following steps S14-S19, including:

[0104] S14. Perform lens distortion correction on the original multi-angle oblique photography outcrop texture image collected by the UAV to obtain a distortion-free multi-angle oblique photography outcrop texture image, and obtain the UAV pose data recorded by the UAV positioning and attitude system, so as to bind the UAV pose data and the distortion-free multi-angle oblique photography outcrop texture image to form a pre-multi-angle oblique photography outcrop texture image.

[0105] S15. Obtain a preset aerial triangulation error threshold, and use the coordinates of the outcrop ground control point to perform multi-view joint adjustment processing on the pre-multi-angle oblique photography outcrop texture image to optimize the aerial triangulation measurement error of the multi-angle oblique photography outcrop texture image to be lower than the preset aerial triangulation error threshold, so as to obtain the multi-angle oblique photography outcrop texture image.

[0106] S16. Using the structure-of-motion algorithm, extract multiple feature points from the multi-angle oblique photography outcrop texture image, perform feature matching on each feature point to generate a multi-view sparse point cloud and a multi-view depth map from the multi-angle oblique photography outcrop texture image, and fuse the multi-view depth map with the multi-view sparse point cloud to obtain a multi-view dense point cloud.

[0107] S17. The Delaunay triangulation algorithm is used to divide the multi-view dense point cloud into multiple sets of non-overlapping triangles to construct an irregular triangular network model.

[0108] S18. Project the multi-angle oblique photographic outcrop texture image onto the surface of the triangular network model, and eliminate the seams between the various mapped images on the surface of the triangular network model to obtain an initial digital outcrop real-world 3D model.

[0109] S19. In the real-world image formed by the initial digital outcrop real-world 3D model, repair the mesh holes caused by vegetation obstruction and simplify the mesh to obtain the digital outcrop real-world 3D model.

[0110] It should be noted that, in one specific implementation, the UAV utilizes oblique photogrammetry technology to construct a realistic 3D model. Model construction requires a systematic data acquisition, processing, and optimization process. First, a UAV flight plan is generated based on geological target information (e.g., paleocurrent analysis of a specific area): a UAV equipped with a five-lens oblique camera and an RTK (Real-Time Kinematic) positioning module is selected. A terrain-following flight path is planned based on the outcrop morphology, while simultaneously controlling the forward overlap rate of each UAV to ≥80% and the lateral overlap to ≥70%. The flight altitude (preferably 50-100 meters) is dynamically adjusted according to the terrain steepness to maintain resolution. Before flight, ground control points (GCPs) are established around the outcrop, and centimeter-level coordinates are obtained using the RTK positioning module for subsequent model accuracy correction. Meanwhile, in the preferred embodiment, the drone flight plan needs to be executed during the daytime, and the flight plan should avoid the period of strong light. The flight and shooting should be completed under cloudy or soft lighting conditions in order to obtain original multi-angle oblique photographic outcrop texture images without shadow interference. In particular, multi-angle oblique shooting is required for key structures such as cross-layering.

[0111] After obtaining the original multi-angle oblique photographic outcrop texture image, it needs to be processed in several ways, including, but not limited to: distortion correction of the original multi-angle oblique photographic outcrop texture image, and data fusion with UAV pose data (Position and Orientation System, POS) to complete image preprocessing; importing GCP coordinates and performing multi-view joint adjustment processing to optimize the aerial triangulation error of the multi-angle oblique photographic outcrop texture image to below the preset aerial triangulation error (the preset aerial triangulation error can generally be set to 0.05m); generating multi-view dense point clouds through the Structure from Motion (SfM) algorithm, and constructing an irregular triangulated network (Triangulated Irregular) using Delaunay triangulation. The network (TIN) model is used, and multi-angle oblique photographic images of the outcrop texture are projected onto the surface of the irregular triangular network model to fuse multi-view textures and generate an initial digital outcrop real-world 3D model. In addition, since the model quality needs to be optimized in geological applications (structural identification), 3D modeling processing software (such as Meshmixer) can be used to repair mesh voids caused by vegetation occlusion in the real-world image formed by the initial digital outcrop real-world 3D model, and simplify the mesh while retaining structural details (such as the trough-shaped interface of trough cross-bedding). Finally, the digital outcrop real-world 3D model is obtained and exported in 3D Tiles format.

[0112] This modeling methodology fully realizes the 3D construction of digital outcrop scenes and effectively improves model accuracy. The constructed 3D digital outcrop scene model can display high-resolution texture information, providing a digital model foundation for accurately identifying sedimentary structures indicating paleocurrent directions using the 3D digital outcrop scene model.

[0113] S2. Based on the digital outcrop real-world 3D model, multiple candidate sedimentary paleocurrent direction indicator structures are identified, and the validity of each candidate sedimentary paleocurrent direction indicator structure is verified using virtual auxiliary lines, so that the verified candidate sedimentary paleocurrent direction indicator structures are taken as valid sedimentary paleocurrent direction indicator structures.

[0114] In one possible implementation, step S2, based on the digital outcrop real-world 3D model, identifies multiple candidate sedimentary paleocurrent direction indicator structures, which can be decomposed, but is not limited to, the following steps S21-S25, including:

[0115] S21. Multi-angle real-scene image capture is performed on the digital outcrop real-scene 3D model, and based on the multi-angle real-scene images captured from the digital outcrop real-scene 3D model, different sedimentary cross-bedding structure types are identified, wherein the sedimentary cross-bedding structure types include platy cross-bedding structure, wedge cross-bedding, and trough cross-bedding structure:

[0116] S22. In the aforementioned platy cross-bedding structure, detailed identification is performed on the parallel interfaces between the single layers of the platy cross-bedding and the pre-accretionary laminations with consistent inclination, in order to obtain the first sedimentary structural features.

[0117] S23. In the wedge-shaped cross-bedding structure, the non-parallel cutting relationship between the layers of the wedge-shaped cross-bedding and the oblique cross-bedding features of the laminations and interfaces are identified in detail to obtain the second sedimentary structure features.

[0118] S24. In the trough-shaped cross-bedding structure, the scouring morphology of the trough-shaped bottom interface of the transverse section of the trough-shaped cross-bedding is identified in detail, the relationship between the arc-shaped bottom boundary and the oblique intersecting lamination of the longitudinal section of the trough-shaped cross-bedding is identified in detail, and the petal-shaped overlapping structure of the top view of the trough-shaped cross-bedding is identified in detail, so as to obtain the third sedimentary structure characteristics.

[0119] S25. Obtain preset sedimentary paleocurrent direction indicator markers, and compare the identified first sedimentary structural features, second sedimentary structural features, and third sedimentary structural features with the sedimentary paleocurrent direction indicator markers respectively, so as to select candidate sedimentary paleocurrent direction indicator structures from the digital outcrop real-world 3D model;

[0120] Accordingly, in step S2, the validity of each candidate paleocurrent direction indicator structure is verified using virtual auxiliary lines, so that the verified candidate paleocurrent direction indicator structures are considered as valid paleocurrent direction indicator structures. This can be decomposed into, but is not limited to, the following steps S26-S27, including:

[0121] S26. Based on the sedimentary cross-bedding structure type corresponding to each of the candidate sedimentary paleocurrent direction indicator structures, draw virtual auxiliary lines in the candidate sedimentary paleocurrent direction indicator structures of different sedimentary cross-bedding structure types;

[0122] S27. Based on the consistency of the virtual auxiliary lines, the candidate sedimentary paleocurrent direction indicator structures are validated for effectiveness, and the candidate sedimentary paleocurrent direction indicator structures that pass the validity validation are taken as valid sedimentary paleocurrent direction indicator structures.

[0123] like Figure 2As shown in (a) platy cross-bedding structure, (b) trough cross-bedding structure, and (c) wedge cross-bedding structure, in practical applications, after loading the digital outcrop real-scene 3D model constructed based on UAV oblique photogrammetry onto a 3D engine platform (such as Cesium), it is necessary to identify effective sedimentary paleocurrent direction indicator structures. Examples, but not limited to, include: capturing real-scene images of the model from multiple angles through interactive operations (rotation, scaling, and translation), and combining high-resolution texture information (resolution better than 5 cm / pixel) to identify key sedimentary structures indicating paleocurrent direction. Different sedimentary cross-bedding structures are obtained: for platy cross-bedding structures, the direction of paleocurrent is determined by tracing parallel interfaces between single layers and pre-accretionary lamellars with consistent dips; for wedge-shaped cross-bedding structures, the non-parallel cutting relationship between layers and the oblique intersection feature between lamellars and interfaces can be identified; for trough-shaped cross-bedding structures, different perspectives need to be switched to verify the three-dimensional features. Specifically, the scour morphology of the trough-shaped bottom interface is identified in the transverse section, the oblique intersection relationship between the arc-shaped bottom boundary and lamellars is identified in the longitudinal section, and the petal-like overlapping structure is identified and judged from the top perspective.

[0124] This process relies on the spatial reconstruction capabilities of digital outcrop 3D models of geological phenomena. After identifying multiple candidate paleocurrent direction indicators, a virtual auxiliary line (segment) should be drawn along the pre-accretionary laminar direction of the platy cross-bedding structure, taking platy cross-bedding as an example. If this line segment exhibits a continuous and consistent tilt direction in 3D space (conforming to paleocurrent direction indicators), it can be confirmed as a valid paleocurrent direction indicator. For complex candidate paleocurrent direction indicators (e.g., trough-shaped cross-bedding structures partially covered by vegetation), local magnification and lighting adjustments can enhance texture discernibility, ensuring that microstructures such as trough patterns or ripple marks are not overlooked, thus laying the foundation for accurate subsequent occurrence measurements.

[0125] Different structures are classified and identified to facilitate subsequent occurrence calculations, resulting in more accurate results. Furthermore, the introduction of validity verification reduces the number of valid sedimentary paleocurrent direction indicator structures and increases the number of key features that conform to sedimentary paleocurrent direction indicators, thus avoiding excessive computation and obtaining more representative features. This makes the occurrence calculated in subsequent calculations more representative and is beneficial for confirming the paleocurrent direction.

[0126] S3. For each of the effective sedimentary paleocurrent direction indicator structures, the geometric shape and exposure integrity of the structural surface are determined to obtain a Class I structural surface and a Class II structural surface. The Class I structural surface is used to represent effective sedimentary paleocurrent direction indicator structures with a planar geometric shape and complete exposure of the structural surface. The Class II structural surface is used to represent effective sedimentary paleocurrent direction indicator structures with a vertical geometric shape, a curved geometric shape, or incomplete exposure of the structural surface.

[0127] In one possible implementation, step S3 involves determining the geometric morphology and exposure integrity of each effective sedimentary paleocurrent indicator structure to obtain Class I and Class II structural surfaces. This can be decomposed, but is not limited to, the following steps S31-S32, including:

[0128] S31. Based on the real-scene image of the surface of the digital outcrop real-scene three-dimensional model, the geometric shape of each effective sedimentary paleocurrent direction indicator structure is determined. The effective sedimentary paleocurrent direction indicator structure with the determination result of planar structure is regarded as a pre-classified structure surface, and the effective sedimentary paleocurrent direction indicator structure with the determination result of vertical structure is regarded as a second-class structure surface.

[0129] S32. Based on the real-world image of the surface of the digital outcrop real-world 3D model, the exposure integrity of each of the pre-class I structural surfaces is determined. The pre-class I structural surfaces with complete exposure are designated as Class I structural surfaces, and the pre-class I structural surfaces with incomplete exposure are designated as Class II structural surfaces. In the Class I structural surfaces, the pre-accumulated texture layer is located on the plane where the surface of the Class I structural surface is located and is parallel to the plane where the surface of the Class II structural surface is located. In the Class II structural surfaces, the pre-accumulated texture layer is located inside the Class II structural surface and intersects with the plane where the surface of the Class II structural surface is located.

[0130] S4. For each type of structural surface, a type of structural auxiliary plane is determined in the three-point method in the digital outcrop real-world 3D model. The dip direction, dip angle and normal vector of the type of structural surface are calculated using the type of structural auxiliary plane to obtain the occurrence of an effective sedimentary structural surface.

[0131] In one possible implementation, in step S4, for each type of structural surface, a three-point method is used to determine a structural auxiliary plane in the digital outcrop real-world 3D model. The dip direction, dip angle, and normal vector of the structural surface are then calculated using the structural auxiliary plane to obtain the attitude of an effective sedimentary structural surface. This can be decomposed, but is not limited to, the following steps S41-S44, including:

[0132] S41. Based on the digital outcrop real-world 3D model, select three non-collinear points on the first type of structural surface and obtain the global Cartesian coordinates of the three non-collinear points, so as to fit a first type of structural auxiliary plane through the three non-collinear points, wherein the first type of structural auxiliary plane is parallel to the plane on which the first type of structural surface is located.

[0133] S42. Based on the aforementioned auxiliary construction plane, construct a class of auxiliary construction plane equations, and calculate a class of construction surface normal vectors according to the aforementioned auxiliary construction plane equations;

[0134] S43. Based on the equation of the first type of auxiliary structural plane and the normal vector of the first type of structural plane, the dip direction and dip angle of the first type of structural plane are calculated.

[0135] S44. Integrate the dip direction, dip angle, and normal vector of the aforementioned structural surface to form an effective sedimentary structural plane orientation.

[0136] Based on a digital outcrop 3D model, the attitude of a type of structural surface is calculated (e.g., measuring the paleocurrent direction of cross-bedding structures in sandstone requires determining the maximum dip angle and dip direction of the cross-bedding, as well as the attitude of the stratigraphic group). In traditional field surveying, a compass is typically used to measure the attitude. However, the digital outcrop 3D model constructed using oblique photogrammetry in this embodiment possesses rich spatial coordinate information, making it possible to measure the attitude using this model. The specific approach to measuring the attitude using the three-point method based on the digital outcrop 3D model is as follows: Figure 3 As shown, the model loaded by the 3D engine platform (such as Cesium) is in 3D Tiles format. The surface of the digital outcrop real-scene 3D model is composed of irregular triangular networks (TINs). Through interactive operations, three non-collinear points are randomly selected from a type of structural surface on the model to form a type of structural auxiliary plane. Using 3D spatial geometric relationships and coordinate transformations, the attitude information of the structural surface is obtained. First, the point coordinates of the 3D Tiles format model are obtained using the interface provided by Cesium. In the digital outcrop real-scene 3D model, when the image of a type of structural surface is rendered to the screen, the depth value of each pixel (i.e., the depth value in the viewing direction) is stored in a depth buffer. Figure 3 (The direction of the Z-axis). At this point, based on the window coordinates, the corresponding position is picked from the depth buffer. The two-dimensional coordinates on the screen are converted into points in three-dimensional space using the view matrix and projection matrix to return the global three-dimensional Cartesian coordinates of three non-collinear points. A class of auxiliary planes is constructed by fitting these three non-collinear points, the normal vector of the plane is calculated, and its dip and tilt angle are obtained. The tilt angle is the angle between the normal vector and the horizontal plane. This is obtained by calculating the normal vector and the vertical vector (…). Figure 3The angle between the unit vectors along the Z-axis is used to determine the direction of inclination. The dip direction is the downward slope of the plane, usually represented by the angle between the projection of the normal vector onto a type of auxiliary plane and the true north direction.

[0137] like Figure 3 As shown, in practical applications, this embodiment provides, but is not limited to, a specific method and three-point method for calculating the planar occurrence of a class of effective sedimentary structures. This does not constitute a limitation on the calculation method of this scheme.

[0138] Given the coordinates of three non-collinear points, P1(x1,y1,z1), P2(x2,y2,z2), and P3(x3,y3,z3), calculate the vector of two points sharing the same origin. and

[0139]

[0140] Construct a class of auxiliary planes, and the normal vector of this plane (a class of construction plane normal vectors) is given. It is possible to calculate vectors and The cross product yields:

[0141]

[0142] Substituting the coordinates of P1(x1,y1,z1), P2(x2,y2,z2), and P3(x3,y3,z3), we can calculate:

[0143]

[0144] For a class of constructed auxiliary planes, if we fit the equation AX + BY + CZ + D = 0, then the solutions A, B, C, and D are as follows:

[0145]

[0146] A class of surface normal vectors The components (projections) in the three axes are and (Right now Figure 3 Given a, b, and c), the relationship between the dip α of one type of structural surface and the dip angle β of another type of structural surface is:

[0147]

[0148] Then the dip angle β of a type of structural surface can be obtained through the normal vector of a type of structural surface. The angular relationship with the vertically upward unit vector is expressed as follows:

[0149]

[0150] For a class of structural planes, the dip angle α ranges from 0 to 360°, therefore different scenarios need to be considered when calculating the dip angle. Specifically:

[0151] when hour,

[0152]

[0153] like Then we have:

[0154]

[0155] like Then we have:

[0156]

[0157] when hour,

[0158]

[0159] like Then we have:

[0160]

[0161] like Then we have:

[0162]

[0163] Based on the obtained dip direction, dip angle, and normal vector of a type of structural surface, the effective sedimentary structural plane orientation can be obtained.

[0164] S5. For each type II structural surface, the pre-accretionary laminae in each type II structural surface are identified in the digital outcrop real-world 3D model, and the type II structural auxiliary plane is determined based on the pre-accretionary laminae. The dip direction, dip angle and normal vector of the type II structural surface are calculated using the type II structural auxiliary plane to obtain the occurrence of the type II effective sedimentary structural plane.

[0165] In one possible implementation, in step S5, for each type II structural surface, the pre-accretionary striations in each type II structural surface are identified in the digital outcrop real-world 3D model, and a type II structural auxiliary plane is determined based on the pre-accretionary striations. The dip direction, dip angle, and normal vector of the type II structural surface are calculated using the type II structural auxiliary plane to obtain the attitude of the effective type II sedimentary structural plane. This can be, but is not limited to, decomposed into the following steps S51-S58, including:

[0166] S51. Based on the digital outcrop real-world 3D model, identify the pre-aggregate striations on the second type of structural surface to obtain the pre-aggregate striation direction;

[0167] S52. On the type II structural surface, select two points along the direction of the pre-accumulation layer, and select a point on the type II structural surface that is not in the direction of the pre-accumulation layer;

[0168] S53. Obtain the global Cartesian coordinates of two points in the direction of the pre-integral texture layer and a point not in the direction of the pre-integral texture layer, so as to fit a pre-type II construction auxiliary plane through these three points, wherein the pre-type II construction auxiliary plane is perpendicular to the plane where the pre-integral texture layer is located;

[0169] S54. Based on the pre-class II construction auxiliary plane, construct the equation of the pre-class II construction auxiliary plane, and calculate the normal vector of the pre-class II construction surface according to the equation of the pre-class II construction auxiliary plane;

[0170] S55. Based on the pre-type II construction auxiliary plane and the normal vector of the pre-type II construction surface, a type II construction auxiliary plane perpendicular to the pre-type II construction auxiliary plane is constructed, wherein the type II construction auxiliary plane is parallel to the plane where the pre-integral texture layer is located;

[0171] S56. Based on the two types of auxiliary construction planes, construct the equations of the two types of auxiliary construction planes, and calculate the normal vectors of the two types of construction surfaces according to the two types of auxiliary construction planes;

[0172] S57. Based on the equation of the secondary structural auxiliary plane and the normal vector of the secondary structural surface, the dip direction and dip angle of the secondary structural surface are calculated.

[0173] S58. Integrate the dip direction of the two types of structural surfaces, the dip angle of the two types of structural surfaces, and the normal vector of the two types of structural surfaces to form the occurrence of the two types of effective sedimentary structural planes.

[0174] like Figure 4 As shown, it should be noted that when measuring the attitude of an effective sedimentary structural plane, it is necessary to use an interactive method to construct a structural auxiliary plane by selecting three non-collinear points on the digital outcrop's 3D model for attitude measurement. However, when measuring the effective sedimentary paleocurrent indicator structure of an elevation-shaped structure, the structural auxiliary plane (pre-class II structural auxiliary plane) formed by three non-collinear points selected on the second-class structural surface is as follows: Figure 4As shown in (a), this clearly cannot represent the effective sedimentary paleocurrent indicator structure (progradational laminae) of the facade structure. The results obtained from calculations using this structure are naturally not the attitude data of the progradational laminae. This is because the facade structure only exposes its sides at the outcrop, and it is impossible to represent the surface where the progradational laminae are located using a pre-type II structure auxiliary plane formed by three non-collinear points selected on the digital outcrop real-world 3D model; that is, points extending into the structure surface cannot be selected. Therefore, this embodiment provides, but is not limited to, a calculation method and auxiliary plane processing principle for measuring the attitude of progradational laminae on facade structures. This does not constitute a limitation on the calculation method of this scheme: Figure 4 As shown in (b), firstly, the pre-accretionary striations on the type II structural surface are identified to obtain the direction of the pre-accretionary striations. Two points A and B are drawn along the direction of the pre-accretionary striations. An arbitrary point C is selected on the elevation surface that is not on the line containing A and B. It is required that the auxiliary plane for the pre-type II structure formed by the three points A, B, and C is perpendicular to the plane containing the pre-accretionary striations. Secondly, in accordance with the above... Figure 3 The three-point method shown follows the same calculation principle, and the normal vector of the pre-class II structural surface is calculated as follows: To measure the attitude of the pre-integral striations, it is necessary to construct a vector... and the normal vector of the pre-class II construction surface The newly formed plane (the normal vector of the pre-class II construction surface), i.e. Figure 4 As shown in (b), surface ABB′A′ is perpendicular to the pre-type II structural auxiliary plane ABC. Surface ABB′A′ is the plane containing the pre-accretionary striations (type II structural auxiliary plane), and the normal vector of the type II structural surface is... Through the normal vector of the second type of construction surface With the above Figure 3 The three-point method shown uses the same calculation principle to calculate the dip and dip angle of the second-type structural surface. Based on the obtained dip, dip angle, and normal vector of the second-type structural surface, the attitude of the first-type effective sedimentary structural plane can be obtained.

[0175] S6. Obtain the stratigraphic strike vector, and perform attitude correction on the attitude of each of the first-class effective sedimentary structure planes and each of the second-class effective sedimentary structure planes according to the stratigraphic strike vector to obtain the corrected attitude data;

[0176] In one possible implementation, step S6, before obtaining the stratigraphic strike vector, may also include, but is not limited to, the following steps S601-S603:

[0177] S601. Using linear interpolation, multiple equidistant interpolation points are generated between any two edge points of the pre-aggregate texture on each of the first-type structural surfaces, and multiple equidistant interpolation points are generated between two edge points in the direction of the pre-aggregate texture on each of the second-type structural surfaces.

[0178] S602. For each interpolation point, calculate the intersection point between the interpolation point and the first type of structural surface or the second type of structural surface, and perform intersection point calculation to obtain multiple intersection points;

[0179] S603. On each of the first-type structural surfaces and each of the second-type structural surfaces, the distances between each adjacent intersection point are calculated sequentially and summed to calculate the real-world distance measurement results of the pre-accretionary texture layers of each of the first-type structural surfaces and each of the second-type structural surfaces.

[0180] like Figure 5 As shown, since the results of the real-world distance measurement of the pre-aggregate stratigraphy are needed for real-world annotation in subsequent paleocurrent analysis, this embodiment also provides, but is not limited to, a method for spatial distance measurement on a digital outcrop real-world 3D model. Specifically: First, as... Figure 5 As shown in (a), the position coordinates A(x1,y1,z1) and B(x2,y2,z2) of any two edge points of the pre-integral layer in the three-dimensional Cartesian coordinate system are obtained, and then the spatial distance between the two edge points is calculated.

[0181] Secondly, using linear interpolation, multiple equidistant interpolation points are generated between points A and B. The path length between points A and B along the surface of the digital outcrop real-world 3D model is determined by intersecting the model surface. That is, by generating a series of equidistant interpolation points between points A and B, and calculating the intersection points of these interpolation points with the first or second type of structural surface, the actual path length (real-world distance calculation result) is estimated by the sum of the distances between the two points.

[0182] The results of the real-world distance measurement can be used as an auxiliary factor in the analysis of paleocurrent direction. In addition, preferably, the real-world distance measurement results can be used to mark the outcrops on the final digital outcrop real-world 3D model to facilitate the determination of the actual distance.

[0183] In one possible implementation, step S6, obtaining the stratigraphic strike vector, can be decomposed into, but is not limited to, the following steps S61-S64, including:

[0184] S61. Based on the digital outcrop real-world 3D model, project and determine the stratigraphic planes of the first type of structural surface and the second type of structural surface;

[0185] S62. For the stratigraphic planes of the first type of structural surface and the second type of structural surface, construct stratigraphic plane equations, and calculate stratigraphic plane normal vectors based on the stratigraphic plane equations;

[0186] S63. Based on the stratigraphic plane equation and the stratigraphic plane normal vector, the dip direction and dip angle of the stratigraphic plane are calculated;

[0187] S64. Based on the dip direction of the stratigraphic plane, the dip direction of the stratigraphic plane, the normal vector of the stratigraphic plane, the attitude of the first type of effective sedimentary structure plane, and the attitude of the second type of effective sedimentary structure plane, calculate the stratigraphic strike vector;

[0188] Accordingly, in step S6, the attitude correction of each of the first-class effective sedimentary structural planes and each of the second-class effective sedimentary structural planes is performed based on the stratigraphic strike vector to obtain the corrected attitude data. This can be decomposed into, but is not limited to, the following steps S65-S610, including:

[0189] S65. A three-dimensional calibration coordinate system is defined with the starting point of the strike vector of the strata as the origin, the strike vector of the strata as the Y-axis, and the direction of the normal vector of the strata plane as the Z-axis.

[0190] S66. Place the normal vector of the first type of structural surface in the three-dimensional correction coordinate system, and determine whether the normal vector of the first type of structural surface is perpendicular to the Y-axis of the three-dimensional correction coordinate system;

[0191] If so, the dip direction, dip angle, and normal vector of the first type of structural surface are integrated to form the corrected effective sedimentary structural plane orientation.

[0192] If not, the normal vector of the first type of structural surface is corrected to a vector perpendicular to the Y-axis of the three-dimensional correction coordinate system to form a corrected normal vector of the first type of structural surface. Based on the corrected normal vector of the first type of structural surface, the dip direction and dip angle of the corrected first type of structural surface are calculated. The dip direction, dip angle, and normal vector of the corrected first type of structural surface are then integrated to form the orientation of the corrected effective sedimentary structural plane.

[0193] S67. Place the type II construction surface normal vector in the three-dimensional correction coordinate system, and rotate the type II construction surface normal vector around the Y-axis of the three-dimensional correction coordinate system with the origin of the three-dimensional correction coordinate system as the starting point to form a normal vector cone;

[0194] S68. Based on the normal vector cone, the normal vectors of the two types of structural surfaces are corrected to obtain the corrected normal vectors of the two types of structural surfaces;

[0195] S69. Based on the corrected type II structural surface normal vector, calculate the corrected type II structural surface dip and dip angle, and integrate the corrected type II structural surface dip, dip angle and normal vector to serve as the corrected type II effective sedimentary structural plane orientation;

[0196] S610. Integrate the corrected first-class effective sedimentary structure plane occurrences and the corrected second-class effective sedimentary structure plane occurrences to form corrected occurrence data.

[0197] like Figure 6 As shown, after completing the measurement of the plane orientation of effective sedimentary structures of type I and type II, a large amount of orientation data will be obtained in this embodiment. In order to save manpower costs and reduce workload, this embodiment preferably uses WebGIS (Web Geographic Information System) to realize batch orientation correction. The purpose of orientation correction is to help restore the spatial orientation of the pre-sedimentary layer in ancient times (when it was formed).

[0198] Therefore, this embodiment provides, but is not limited to, a specific method and geometric processing principle for attitude correction calculation. This does not constitute a limitation on the calculation method flow of this scheme. Specifically, for the second type of structural surface: First, based on the digital outcrop real-scene 3D model, the stratigraphic planes of the first type of structural surface and the second type of structural surface are projected and determined, and the stratigraphic strike vector is obtained. With the stratigraphic strike vector as the axis (as the rotation axis), through rotation and 3D spatial geometric transformation, the stratigraphy is adjusted from its existing dip state to the theoretical horizontal position, and the attitude of the pre-accretionary stratigraphy is obtained at this time.

[0199] Secondly, based on the stratigraphic normal vector and the normal vector of the second type of structural surface, and considering the perpendicular relationship between the dip and strike, the strike angle is calculated by subtracting 90° from the dip angle. If the result is negative, 360° is added to ensure it falls within the range of 0°-360°, guaranteeing a non-negative angle value. The stratigraphic strike vector is denoted as N0. When the stratigraphic plane rotates clockwise around the strike vector N0 by an angle α, the stratigraphic plane becomes horizontal. When the normal vector of the second type of structural surface N1 rotates clockwise around the strike vector N0 by the same angle α, the corrected normal vector of the second type of structural surface after the dip has subsided is obtained, i.e., the corrected normal vector N2. Based on the relationship between the corrected normal vector N2 and the dip and dip angle, the dip and dip angle of the pre-accretionary layer can be deduced. The specific calculation process for the corrected normal vector N2 is as follows:

[0200] Rotate the normal vector N1 of the type II structural surface around the strike vector N0 of the strata to obtain a normal vector cone. Then, for this normal vector cone, first calculate the cosine value of the cone apex angle 'b' of the rotation of the normal vector N1 of the type II structural surface around the strike vector N0 of the strata using the following formula:

[0201]

[0202] If the normal vector N1 of the second type of structural surface and the strike vector N0 of the strata are taken as unit vectors, then formula (13) can be simplified to:

[0203] cos(b)=N0·N1 (14)

[0204] The vector pointing from the origin O to the center O' of the base of the normal vector cone is OO', where OO' is the direction (Y-axis) along the strike vector N0 of the strata, and its length is the projection of the normal vector N1 of the second type of structural surface onto the direction (Y-axis) of the strike vector N0 of the strata.

[0205] OO'= N0cos(b) (15)

[0206] The vector R1, with a radius equal to the length of the radius pointing from the center O' of the base of the normal vector cone to the normal vector N1 of the second type of construction surface, is represented as:

[0207] R1=N1-N0cos(b) (16)

[0208] Correspondingly, the vector R2, whose length is the radius, points from the center O' of the base of the normal vector cone to the corrected normal vector N2, and can be expressed as:

[0209] R2=N2-N0cos(b) (17)

[0210] The projection O'A of vector R2 onto the direction of R1 and the component AB perpendicular to the direction of R1 are:

[0211]

[0212] R 2⊥ =AB=(R1×N0)sin(a) (19)

[0213] Therefore, vector R2 is the sum of O'A and AB:

[0214] R2 = R 2|| +R 2⊥ =R1cos(a)+(R1×N0)sin(a) (20)

[0215] At this point, both formula (17) and formula (20) represent R2. Combining the two formulas, we can obtain the corrected normal vector N2 as follows:

[0216] N2=(N0·N1)N0(1-cos(a))+N1cos(a)+(N1×N0)sin(a) (21)

[0217] Meanwhile, during the above-mentioned attitude correction process, the range of values ​​for all attitude data should be determined in advance to ensure that all attitude data entering the attitude correction process (i.e., step 6) (including the attitude of type I effective sedimentary structural planes and type II effective sedimentary structural planes) are within the valid range of values. The dip and dip angle values ​​should conform to their defined range (0°-360°) to avoid generating invalid or meaningless results (such as negative angles or angles exceeding 360°). In the calculation process of attitude correction, the large amount of data can easily lead to confusion. Therefore, it is necessary to process the attitudes of each type I and type II effective sedimentary structural planes in batches. For each set of type I and type II effective sedimentary structural plane attitudes, a corresponding structural plane attitude dataset is formed, and a corresponding stratigraphic plane dataset (including the stratigraphic plane dip, stratigraphic plane dip angle, stratigraphic plane normal vector, and stratigraphic strike vector) is generated for each structural plane attitude dataset. A loop structure is used to iteratively process these datasets, enabling WebGIS to complete batch data processing and output the final correction results at once, thereby improving correction efficiency.

[0218] By correcting the attitude, the dip angle of the pre-accretionary laminae is geometrically transformed to eliminate the influence of tectonic deformation on the attitude data, thus helping to restore the true paleocurrent direction during the depositional period.

[0219] S7. Based on the corrected occurrence data, perform sedimentary paleocurrent direction analysis to obtain the sedimentary paleocurrent direction analysis results, and visualize the sedimentary paleocurrent direction analysis results, wherein the sedimentary paleocurrent direction analysis results include a paleocurrent direction rose diagram.

[0220] In one possible implementation, step S7 involves performing a paleocurrent analysis based on the corrected occurrence data to obtain the paleocurrent analysis results, and then visualizing these results. This step can be broken down into, but is not limited to, the following steps S71-S74, including:

[0221] S71. Perform outlier cleaning on the corrected structural surface dip data and corrected structural surface dip angle data in the corrected attitude data, wherein the corrected structural surface dip data includes corrected type I structural surface dip and corrected type II structural surface dip, and the corrected structural surface dip angle data includes corrected type I structural surface dip angle and corrected type II structural surface dip angle.

[0222] S72. Establish a blank rose diagram, divide the 360° orientation circle in the blank rose diagram into 36 angle intervals, and for each angle interval, count the frequency of the data points generated by the corrected attitude data after outlier cleaning falling into each angle interval.

[0223] S73. Based on the frequency of data points falling into the corrected attitude data in each angle interval, draw rose petals for the corresponding angle interval in the blank rose diagram to form an ancient flow direction rose diagram. The angle interval with the longest rose petal in the ancient flow direction rose diagram is taken as the ancient flow direction analysis result, and the ancient flow direction analysis result is used to represent the dominant direction of ancient water flow.

[0224] S74. The paleocurrent rose diagram is used as the result of the sedimentary paleocurrent analysis and visualized.

[0225] like Figure 7 (A) and (B) are schematic diagrams illustrating the paleocurrent analysis results and rose diagrams for two outcrops, respectively. It should be noted that this embodiment uses a rose diagram as the chart for paleocurrent statistics and display. However, this is only a visually intuitive and preferred method of display. It should be understood that other statistical charts beneficial for paleocurrent analysis and data display can be obtained and visualized based on the corrected attitude data analysis, such as histograms and pole plots. A rose diagram is a statistical graph used to display directional and angular data. It has three main forms: unidirectional, bidirectional, and multidirectional rose diagrams. Unidirectional rose diagrams are typically used to display data emanating from a fixed point in a single direction; bidirectional rose diagrams show the distribution of data in relative directions; multidirectional rose diagrams can display data distribution in multiple directions and are suitable for analyzing complex datasets with multiple variable directions. In paleocurrent rose diagrams, different rose diagrams correspond to different paleocurrent patterns.

[0226] In one possible implementation, after visualizing the results of the paleocurrent analysis, step S7 may also include, but is not limited to, the following steps S751-S754:

[0227] S751. Based on the corrected occurrence data and the paleocurrent rose diagram, the paleocurrent analysis results are marked in the real-scene images of each outcrop in the digital outcrop real-scene 3D model.

[0228] S752. The actual distance calculation results of the pre-accretionary striations of each of the first-type structural surfaces and each of the second-type structural surfaces are respectively marked on each of the first-type structural surfaces and each of the second-type structural surfaces in the digital outcrop real-scene three-dimensional model to form a paleocurrent analysis model;

[0229] S753. Store the paleocurrent analysis model and complete its visualization.

[0230] like Figure 8 ((a) and (b) are schematic diagrams showing the paleocurrent analysis results and paleocurrent markings for the two outcrops, respectively.) Figure 9 As shown, this embodiment also provides a method for displaying paleocurrent directions on a digital outcrop 3D model, serving as a method for statistical analysis and visualization of paleocurrents. When researchers observe the pre-accretionary stratigraphy on the digital outcrop 3D model, a 3D paleocurrent arrow appears at that location, marking the paleocurrent analysis results. This method allows for a more intuitive display of the paleocurrent direction in the digital outcrop 3D model, effectively overcoming the limitations of traditional 2D photographs in displaying paleocurrents. For example, when the paleocurrent direction is perpendicular to the screen, the arrow in a 2D photograph will only appear as a point, failing to accurately represent the direction. On the paleocurrent analysis model marked with paleocurrent annotations, users can freely adjust the viewing angle and observation point position through interactive operations such as rotation and scaling, facilitating observation of the outcrop from multiple perspectives and obtaining relevant information from the paleocurrent analysis results intuitively, comprehensively, and completely.

[0231] like Figure 10 As shown, the second aspect of this embodiment provides an electronic device, including: a memory, a processor, and a transceiver connected in sequence, wherein the memory is used to store a computer program, the transceiver is used to send and receive messages, and the processor is used to read the computer program and execute the sedimentary paleocurrent analysis method based on a digital outcrop real-scene three-dimensional model as described in the first aspect of the embodiment.

[0232] The working process, working details and technical effects of the electronic device provided in this embodiment can be found in the first aspect of the embodiment, and will not be repeated here.

[0233] The fourth aspect of this embodiment provides a computer program product containing instructions that, when executed on a computer, cause the computer to perform the sedimentary paleocurrent analysis method based on a digital outcrop real-world 3D model as described in the first aspect of this embodiment, wherein the computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device.

[0234] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for analyzing paleocurrent direction of deposition based on a digital outcrop real scene three-dimensional model, characterized in that, The method comprises the following steps: obtaining outcrop ground control point three-dimensional coordinates and original multi-angle oblique photography outcrop texture images, preprocessing the original multi-angle oblique photography outcrop texture images to obtain multi-angle oblique photography outcrop texture images, and performing multi-view image processing by using the outcrop ground control point coordinates to construct a triangular network model, and performing texture mapping on the multi-angle oblique photography outcrop texture images on the triangular network model to generate a digital outcrop real scene three-dimensional model; based on the digital outcrop real scene three-dimensional model, a plurality of candidate sedimentary paleocurrent direction indicating structures are identified, and the effectiveness of each candidate sedimentary paleocurrent direction indicating structure is verified by using a virtual auxiliary line, so that the candidate sedimentary paleocurrent direction indicating structures that pass the verification are used as effective sedimentary paleocurrent direction indicating structures; for each of the effective sedimentary paleocurrent direction indicating structures, the geometric shape and the exposure integrity of the structure surface are determined respectively to obtain a first type of structure surface and a second type of structure surface, wherein the first type of structure surface is used to represent an effective sedimentary paleocurrent direction indicating structure with a planar geometric shape and a complete structure surface exposure, and the second type of structure surface is used to represent an effective sedimentary paleocurrent direction indicating structure with a vertical geometric shape, a curved geometric shape or an incomplete structure surface exposure; for each of the first type of structure surfaces, a first type of structure auxiliary plane is determined in the digital outcrop real scene three-dimensional model by using a three-point method, and a first type of structure surface dip, a first type of structure surface dip angle and a first type of structure surface normal vector are calculated by using the first type of structure auxiliary plane to obtain a first type of effective sedimentary structure plane attitude; for each of the second type of structure surfaces, a prograding laminae in each of the second type of structure surfaces is identified in the digital outcrop real scene three-dimensional model, and a second type of structure auxiliary plane is determined according to the prograding laminae, and a second type of structure surface dip, a second type of structure surface dip angle and a second type of structure surface normal vector are calculated by using the second type of structure auxiliary plane to obtain a second type of effective sedimentary structure plane attitude; obtaining a stratum trend vector, and correcting the attitude of each of the first type of effective sedimentary structure plane attitude and each of the second type of effective sedimentary structure plane attitude according to the stratum trend vector to obtain corrected attitude data; based on the corrected attitude data, sedimentary paleocurrent direction analysis is performed to obtain a sedimentary paleocurrent direction analysis result, and the sedimentary paleocurrent direction analysis result is visualized, wherein the sedimentary paleocurrent direction analysis result comprises a paleocurrent rose diagram.

2. The method of claim 1, wherein, obtaining outcrop ground control point three-dimensional coordinates and original multi-angle oblique photography outcrop texture images comprises: obtaining geological target information, and generating a UAV flight plan based on the geological target information, wherein the geological target information comprises paleocurrent analysis requirements, target outcrop locations and geomorphological information; according to the geological target information, ground control points are laid out at the target outcrop locations to obtain outcrop ground control point three-dimensional coordinates; based on the UAV flight plan, a UAV shooting module is configured and a UAV flight route is planned, and multi-angle oblique photography is performed on the target outcrop according to the UAV flight route to obtain original multi-angle oblique photography outcrop texture images; Correspondingly, the original multi-angle oblique photography outcrop texture image is preprocessed to obtain a multi-angle oblique photography outcrop texture image, and the outcrop ground control point coordinates are used for multi-view image processing to construct a triangular network model. The multi-angle oblique photography outcrop texture image is texture mapped on the triangular network model to generate a digital outcrop real scene three-dimensional model, which comprises: The original multi-angle oblique photography outcrop texture image collected by the unmanned aerial vehicle is subjected to lens distortion correction to obtain a non-distorted multi-angle oblique photography outcrop texture image, and the unmanned aerial vehicle pose data recorded by the unmanned aerial vehicle positioning and orientation system is obtained to bind the unmanned aerial vehicle pose data and the non-distorted multi-angle oblique photography outcrop texture image to form a pre-multi-angle oblique photography outcrop texture image. A preset aerial triangulation error threshold is obtained, and the pre-multi-angle oblique photography outcrop texture image is subjected to multi-view image joint adjustment processing using the outcrop ground control point coordinates to optimize the aerial triangulation error of the multi-angle oblique photography outcrop texture image to be lower than the preset aerial triangulation error threshold to obtain a multi-angle oblique photography outcrop texture image. A plurality of feature points are extracted from the multi-angle oblique photography outcrop texture image using a motion recovery structure algorithm, and each feature point is subjected to feature matching to generate a multi-view sparse point cloud and a multi-view depth map for the multi-angle oblique photography outcrop texture image. The multi-view depth map and the multi-view sparse point cloud are fused to obtain a multi-view dense point cloud. The multi-view dense point cloud is segmented into a plurality of non-overlapping triangular sets using a Delaunay triangulation algorithm to construct an irregular triangular network model. The multi-angle oblique photography outcrop texture image is projected onto the surface of the triangular network model, and the seams between each mapping image on the surface of the triangular network model are eliminated to obtain an initial digital outcrop real scene three-dimensional model. In the real scene image formed by the initial digital outcrop real scene three-dimensional model, grid holes caused by vegetation obstruction are repaired, and the grid is simplified to obtain a digital outcrop real scene three-dimensional model.

3. The method of claim 1, wherein, Based on the digital outcrop real scene three-dimensional model, a plurality of candidate sedimentary paleocurrent direction indicating structures are identified, which comprises: Multi-angle real scene images are captured from the digital outcrop real scene three-dimensional model, and different sedimentary cross-bedding structure types are identified based on the multi-angle real scene images captured from the digital outcrop real scene three-dimensional model, wherein the sedimentary cross-bedding structure types include tabular cross-bedding structure, wedge-shaped cross-bedding structure, and slot-shaped cross-bedding structure: In the tabular cross-bedding structure, the parallel interfaces between single layers of tabular cross-bedding and the foreset laminae with consistent tendency are identified in detail to obtain first sedimentary structure features; In the wedge-shaped cross-bedding structure, the non-parallel cutting relationship between layer systems of wedge-shaped cross-bedding and the oblique intersection features of laminae and interfaces are identified in detail to obtain second sedimentary structure features; In the slot-shaped cross-bedding structure, the parallel cutting relationship between layer systems of slot-shaped cross-bedding and the oblique intersection features of laminae and interfaces are identified in detail to obtain third sedimentary structure features. In the slot-shaped cross-bedding structure, the slot-shaped bottom interface of the cross-bedding is identified in detail, the arc-shaped bottom interface of the cross-bedding is identified in detail, and the petal-shaped overlapping structure of the top view of the cross-bedding is identified in detail to obtain a third sedimentary structure feature; A preset sedimentary paleocurrent direction indicator is obtained, and the first sedimentary structure feature, the second sedimentary structure feature and the third sedimentary structure feature are compared with the sedimentary paleocurrent direction indicator to select a candidate sedimentary paleocurrent direction indicator structure from the digital outcrop real scene three-dimensional model. Correspondingly, for each candidate sedimentary paleocurrent direction indicator structure, a virtual auxiliary line is used for effectiveness verification to obtain an effective sedimentary paleocurrent direction indicator structure, including: According to the sedimentary cross-bedding structure type corresponding to each candidate sedimentary paleocurrent direction indicator structure, a virtual auxiliary line is drawn on the candidate sedimentary paleocurrent direction indicator structure of different sedimentary cross-bedding structure types. According to the consistency of the inclination of the virtual auxiliary line, the effectiveness of the candidate sedimentary paleocurrent direction indicator structure is verified, and the candidate sedimentary paleocurrent direction indicator structure that passes the effectiveness verification is taken as an effective sedimentary paleocurrent direction indicator structure.

4. The method of claim 1, wherein, For each effective sedimentary paleocurrent direction indicator structure, a structure surface geometric shape and an exposure integrity are determined to obtain a first structure surface and a second structure surface, including: According to the real scene image of the surface of the digital outcrop real scene three-dimensional model, the geometric shape of the structure surface of each effective sedimentary paleocurrent direction indicator structure is determined, and the effective sedimentary paleocurrent direction indicator structure with a planar structure is taken as a first structure surface, and the effective sedimentary paleocurrent direction indicator structure with a vertical structure is taken as a second structure surface. According to the real scene image of the surface of the digital outcrop real scene three-dimensional model, the exposure integrity of each first structure surface is determined, and the first structure surface with complete structure surface exposure is taken as a first structure surface, and the first structure surface with incomplete structure surface exposure is taken as a second structure surface, wherein, in the first structure surface, the foreset beddings are on the plane where the surface of the first structure surface is located, and are parallel to the plane where the surface of the second structure surface is located, and in the second structure surface, the foreset beddings are inside the second structure surface, and intersect with the plane where the surface of the second structure surface is located.

5. The method of claim 1, wherein, For each first structure surface, a first structure auxiliary plane is determined in the digital outcrop real scene three-dimensional model by using a three-point method, and a first structure surface inclination, a first structure surface dip angle and a first structure surface normal vector are calculated by using the first structure auxiliary plane to obtain a first effective sedimentary structure plane occurrence, including: Based on the digital outcrop real scene three-dimensional model, three non-collinear points are selected on the first structure surface, and global Cartesian coordinates of the three non-collinear points are obtained to fit a first structure auxiliary plane by using the three non-collinear points, wherein the first structure auxiliary plane is parallel to the plane where the first structure surface is located. Based on the one type of construction auxiliary plane, a one type of construction auxiliary plane equation is constructed, and a one type of construction plane normal vector is calculated according to the one type of construction auxiliary plane equation; According to the one type of construction auxiliary plane equation and the one type of construction plane normal vector of the one type of construction auxiliary plane, a one type of construction plane tendency and a one type of construction plane inclination are calculated; The one type of construction plane tendency, the one type of construction plane inclination and the one type of construction plane normal vector are integrated as a one type of effective sedimentary structure plane occurrence.

6. The method of claim 1, wherein, For each two type of construction plane, a foreset laminae in each two type of construction plane is identified in the digital outcrop real scene three-dimensional model, and a two type of construction auxiliary plane is determined according to the foreset laminae, and a two type of construction plane tendency, a two type of construction plane inclination and a two type of construction plane normal vector are calculated by using the two type of construction auxiliary plane, so as to obtain a two type of effective sedimentary structure plane occurrence, comprising: Based on the digital outcrop real scene three-dimensional model, a foreset laminae direction is obtained by identifying the foreset laminae on the two type of construction plane; Two points are selected along the foreset laminae direction on the two type of construction plane, and a point not on the foreset laminae direction is selected on the two type of construction plane; Global Cartesian coordinates of the two points on the foreset laminae direction and the point not on the foreset laminae direction are obtained, so as to fit a pre-two type of construction auxiliary plane by using the three points, wherein the pre-two type of construction auxiliary plane is perpendicular to the plane where the foreset laminae is located; Based on the pre-two type of construction auxiliary plane, a pre-two type of construction auxiliary plane equation is constructed, and a pre-two type of construction plane normal vector is calculated according to the pre-two type of construction auxiliary plane equation; Based on the pre-two type of construction auxiliary plane and the pre-two type of construction plane normal vector, a two type of construction auxiliary plane perpendicular to the pre-two type of construction auxiliary plane is constructed, wherein the two type of construction auxiliary plane is parallel to the plane where the foreset laminae is located; Based on the two type of construction auxiliary plane, a two type of construction auxiliary plane equation is constructed, and a two type of construction plane normal vector is calculated according to the two type of construction auxiliary plane; According to the two type of construction auxiliary plane equation and the two type of construction plane normal vector of the two type of construction auxiliary plane, a two type of construction plane tendency and a two type of construction plane inclination are calculated; The two type of construction plane tendency, the two type of construction plane inclination and the two type of construction plane normal vector are integrated as a two type of effective sedimentary structure plane occurrence.

7. The method of claim 1, wherein, Before obtaining the stratum trend vector, further comprising: A plurality of equidistant interpolation points between any two edge points of the foreset laminae on each one type of construction plane are generated by using a linear interpolation method, and a plurality of equidistant interpolation points between two edge points of the foreset laminae direction on each two type of construction plane are generated; For each interpolation point, an intersection point of the interpolation point and the one type of construction plane or the two type of construction plane is calculated to obtain a plurality of intersection points; On each one type of construction plane and each two type of construction plane, distances between adjacent intersection points are calculated in sequence and summed up to calculate real scene distance measurement results of the foreset laminae of each one type of construction plane and each two type of construction plane, respectively.

8. The method of claim 1, wherein, The stratum trend vector comprises: Based on the digital outcrop real scene three-dimensional model, the stratum plane of the first type of structural plane and the second type of structural plane is projected and determined; The stratum plane equation of the first type of structural plane and the second type of structural plane is constructed, and the stratum plane normal vector is calculated according to the stratum plane equation; According to the stratum plane equation and the stratum plane normal vector of the stratum plane, the stratum plane tendency and the stratum plane inclination are calculated; Based on the stratum plane tendency, the stratum plane normal vector, the first type of effective sedimentary structure plane occurrence and the second type of effective sedimentary structure plane occurrence, the stratum trend vector is calculated; Accordingly, the first type of effective sedimentary structure plane occurrence and the second type of effective sedimentary structure plane occurrence are corrected according to the stratum trend vector, and the corrected occurrence data is obtained, which comprises: Taking the starting point of the stratum trend vector as the coordinate origin, the stratum trend vector as the Y-axis axial direction, and the direction of the stratum plane normal vector as the Z-axis axial direction, a three-dimensional correction coordinate system is defined; The first type of structural plane normal vector is placed in the three-dimensional correction coordinate system, and it is judged whether the first type of structural plane normal vector is perpendicular to the Y-axis axial direction of the three-dimensional correction coordinate system; If yes, the first type of structural plane tendency, the first type of structural plane inclination and the first type of structural plane normal vector are integrated as the corrected first type of effective sedimentary structure plane occurrence; If not, the first type of structural plane normal vector is corrected as a vector perpendicular to the Y-axis axial direction of the three-dimensional correction coordinate system to form a corrected first type of structural plane normal vector, the corrected first type of structural plane tendency and the corrected first type of structural plane inclination are calculated based on the corrected first type of structural plane normal vector, and the corrected first type of structural plane tendency, the corrected first type of structural plane inclination and the corrected first type of structural plane normal vector are integrated as the corrected first type of effective sedimentary structure plane occurrence; The second type of structural plane normal vector is placed in the three-dimensional correction coordinate system, and the second type of structural plane normal vector is rotated around the Y-axis axial direction of the three-dimensional correction coordinate system to form a normal vector cone with the origin of the three-dimensional correction coordinate system as the starting point; According to the normal vector cone, the second type of structural plane normal vector is corrected to obtain a corrected second type of structural plane normal vector; Based on the corrected second type of structural plane normal vector, the corrected second type of structural plane tendency and the corrected second type of structural plane inclination are calculated, and the corrected second type of structural plane tendency, the corrected second type of structural plane inclination and the corrected second type of structural plane normal vector are integrated as the corrected second type of effective sedimentary structure plane occurrence; The corrected first type of effective sedimentary structure plane occurrence and the corrected second type of effective sedimentary structure plane occurrence are integrated to form the corrected occurrence data.

9. The method of claim 7, wherein, Based on the corrected occurrence data, sedimentary paleocurrent analysis is carried out to obtain sedimentary paleocurrent analysis results, and the sedimentary paleocurrent analysis results are visualized and displayed, which comprises: The corrected structural surface tendency data and the corrected structural surface dip data in the corrected occurrence data are subjected to outlier cleaning, wherein the corrected structural surface tendency data include corrected first-type structural surface tendency and corrected second-type structural surface tendency, and the corrected structural surface dip data include corrected first-type structural surface dip and corrected second-type structural surface dip; A blank rose diagram is established, and 360° of the blank rose diagram is divided into 36 angle intervals. For each angle interval, the frequency of data points of the corrected occurrence data falling into each angle interval is counted; Based on the frequency of the data points of the corrected occurrence data falling into each angle interval, a rose petal corresponding to each angle interval is drawn in the blank rose diagram, and a paleocurrent rose diagram is formed. The angle interval with the longest rose petal in the paleocurrent rose diagram is taken as a paleocurrent analysis result, and the paleocurrent analysis result is used to represent the dominant direction of the paleocurrent; The paleocurrent rose diagram is taken as a sedimentary paleocurrent analysis result, and is visually displayed.

10. The method of claim 9, wherein, After the sedimentary paleocurrent analysis result is visually displayed, the method further includes: Based on each corrected occurrence data and the paleocurrent rose diagram, the paleocurrent analysis result is marked in a real scene image of each outcrop of the digital outcrop real scene three-dimensional model; The real scene distance measurement result of the foreset bed of each first-type structural surface and each second-type structural surface is marked on each first-type structural surface and each second-type structural surface in the digital outcrop real scene three-dimensional model, so as to form a paleocurrent analysis model; The paleocurrent analysis model is stored and visually displayed.

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