A cross-fault crustal deformation analysis method and system integrating GIS topological analysis technology

Abstract

The present invention provides a cross-fault crustal deformation analysis method and system that integrates GIS topology analysis technology, including: step 1, obtaining a crustal movement velocity field map and a fault distribution map, and overlaying the crustal movement velocity field map and the fault distribution map to display the distribution of stations in the crustal movement velocity field map relative to the faults in the fault distribution map; step 2, based on the distribution of faults in step 1, setting a target area and fault line and obtaining spatial position information of the fault line; step 3, using GIS topology analysis technology to determine the spatial relationship between the stations in the crustal movement velocity field map and the fault line in step 2 and the target area, identifying and extracting the velocity field of the target area; step 4, based on the spatial position information of the fault line in step 2, obtaining cross-fault crustal deformation information based on a profile method. The present invention directly visualizes and quantifies cross-fault crustal deformation information, achieving high efficiency and high accuracy in cross-fault crustal deformation analysis.

Description

Technical Field

[0001] The present invention relates to the field of earth science technology, and in particular to a cross-fault crustal deformation analysis method and system integrating GIS topology analysis technology. Background Art

[0002] Crustal movement is the relative movement between crustal elements caused by the Earth's internal tectonic stresses. It can be divided into vertical and horizontal movement based on the direction of movement. Crustal deformation refers to the rise and fall, tilt, and dislocation of the Earth's crustal surface under the influence of internal and external forces, as well as its corresponding variables. During the strain accumulation stage of crustal movement, the deep fault is locked, while the shallow sections of the fault experience relative creep at different time and space scales, thereby slowly releasing the energy accumulated within the fault and having a certain impact on the development of earthquakes. Therefore, continuous monitoring of crustal deformation in a region can provide important reference data for the study of crustal movement and earthquake prediction.

[0003] Due to the locked state of faults during earthquake development, observing fault motion requires crossing tens of kilometers of elastic deformation zones, making it difficult to continuously monitor fault zone deformation using conventional geodetic surveying. However, in the past two decades, space-based geodetic techniques, such as the Global Navigation Satellite System (GNSS) and Interferometric Synthetic Aperture Radar (InSAR), have improved by two to three orders of magnitude compared to conventional geodetic surveying. This has fundamentally overcome the limitations of conventional geodetic surveying due to topographic constraints, making it possible to measure three-dimensional crustal deformation at multiple spatial scales, with various temporal resolutions, and over a wide frequency domain. Space-based geodetic techniques can play a vital role in monitoring crustal deformation at various spatial and temporal scales, from long-term monitoring of global plate motion, regional crustal deformation, and interseismic deformation along fault zones to monitoring earthquake rupture processes over diverse time periods. However, because the data obtained from processing the observed data yields a crustal velocity field in the Earth coordinate system, the fault motion information contained therein cannot be directly retrieved. Therefore, it is necessary to convert it into the rectangular coordinate system of the fault plane, which is one of the important steps in monitoring fault zone deformation using space geodetic technology.

[0004] A method for monitoring fault zone deformation that is currently widely used and has good results is the velocity profile method. This method usually requires making a profile across the fault, taking the point where the fault is exposed on the surface as the origin, plotting the converted profile velocity into a graph, and performing profile fitting. When no fitting is performed, manually looking at the graph to judge the movement pattern and degree of closure of the fault requires a certain amount of experience. After fitting, the fitting curve can better represent the movement pattern of the fault, and the calculated fault slip rate and fault closure depth can quantitatively describe the movement pattern and degree of closure. In the rectangular coordinate system of the fault plane, V x 、V y and V z is the component of the site velocity, x is the distance perpendicular to the fault strike, δ is the fault dip, V slip and D are the slip rate and locking depth of the fault. For the interseismic deformation of strike-slip and dip-slip faults, the classic elastic screw dislocation model formula is as follows:

[0005]

[0006] In summary, the selection of faults and profile areas is the key to this method. Different profiles under the same fault may extract different station velocities, which in turn leads to differences in the drawn velocity profiles.

[0007] GIS topological analysis technology is a method for processing and analyzing spatial elements (points, lines, and surfaces). Topological analysis can determine and manipulate the spatial relationships (adjacency, containment, and connectivity) between spatial elements. An adjacency relationship indicates that two spatial elements share a common boundary; a containment relationship indicates that a spatial element is completely contained within another surface; and a connectivity relationship indicates that two spatial elements intersect at a single endpoint. By incorporating GIS topological analysis technology into crustal velocity field maps and fault zone distribution maps, by setting a profile area behind the fault line, quantitative information on crustal deformation across faults can be directly obtained using the profile velocity method. Summary of the Invention

[0008] The present invention provides a cross-fault crustal deformation analysis method that integrates GIS topology analysis technology, which solves the shortcoming of traditional velocity profile drawing methods that what you see is what you get, and provides a convenient and accurate method for daily cross-fault crustal deformation analysis work.

[0009] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0010] A cross-fault crustal deformation analysis method integrating GIS topological analysis technology includes the following steps:

[0011] Step 1: Obtain a crustal movement velocity field map and a fault distribution map, and overlap the crustal movement velocity field map and the fault distribution map to display the distribution of the stations in the crustal movement velocity field map relative to the fault distribution map;

[0012] Step 2: According to the distribution of faults in step 1, set the target area and fault line and obtain the spatial position information of the fault line;

[0013] Step 3: Based on GIS topology analysis technology, determine the spatial relationship between the stations in the crustal movement velocity field map and the fault line in step 2 and the target area, and identify and extract the velocity field of the target area;

[0014] Step 4: Based on the spatial position information of the fault line in step 2, information on cross-fault crustal deformation is obtained using a cross-section method.

[0015] Furthermore, the crustal movement velocity field map in step 1 includes discrete site spatial location information and the velocity magnitude and direction at each crustal movement site. The site velocity magnitude and direction are converted into spatial elements to store their information and are displayed in graphs respectively.

[0016] Furthermore, the fault distribution map contains discrete faults, each fault is composed of one to multiple connected line elements, the line represents the spatial position information of the fault, and the fault is converted into a spatial element to store its information and display it in a map.

[0017] Furthermore, the crustal movement velocity field map and the fault distribution map are overlapped, and the site velocity in the crustal movement velocity field map is extracted and plotted on the fault in the fault distribution map, thereby showing the distribution of the site velocity relative to the fault.

[0018] Furthermore, the target area set in step 2 is a surface element, which represents the regional range for cross-fault crustal deformation analysis; the fault line is a line element, which represents the fault for cross-fault crustal deformation analysis and is included in the target area. According to the distribution of site velocity relative to the fault, the target area and fault line required for cross-fault crustal deformation analysis are set and the spatial position information of the fault line is obtained.

[0019] Furthermore, in step 3, GIS topology analysis technology is used to determine the spatial relationship between the target area and the fault line. If the spatial relationship is a containment relationship, the next step is performed; GIS topology analysis technology is used to determine the spatial relationship between the target area and the stations in the crustal movement velocity field map, and the velocities of the stations with a containment relationship are extracted to form the target area velocity field.

[0020] Furthermore, in step 4, the spatial position information of the fault line in step 2 is used, and based on the velocity profile method, the important closure and movement information of the fault is quantitatively calculated to obtain the cross-fault crustal deformation information, including the velocity variation diagram across the fault, the closure degree of the fault and the movement size.

[0021] In another aspect, the present invention provides a cross-fault crustal deformation analysis system using GIS topology analysis technology, comprising:

[0022] Module 1 is used to obtain a crustal movement velocity field map and a fault distribution map, and to overlap the crustal movement velocity field map and the fault distribution map to display the distribution of the stations in the crustal movement velocity field map relative to the fault distribution map;

[0023] Module 2 is used to set the target area and fault line according to the distribution of faults and obtain the spatial position information of the fault line;

[0024] Module 3 is used to determine the spatial relationship between the stations and fault lines in the crustal movement velocity field map and the target area based on GIS topological analysis technology, and to identify and extract the velocity field of the target area;

[0025] Module 4 is used to obtain information on cross-fault crustal deformation based on the spatial position information of the fault line and the cross-fault method.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) The present invention integrates GIS topology analysis technology to simplify and visualize the process of selecting sites by calculation or manually selecting sites, making cross-fault crustal deformation analysis more efficient and accurate, thereby making analysis work a daily routine.

[0028] (2) The present invention is simple and convenient to operate. Users only need to import a crustal velocity field map and a fault distribution map, and they can automatically overlap. Fault lines and target areas can be freely set in the graphical interface, and cross-fault crustal deformation information can be instantly obtained, including cross-fault crustal velocity variation maps, fault movement size, and closure degree. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] Figure 1This is a flow chart of a cross-fault crustal deformation analysis method integrating GIS topology analysis technology in specific embodiment 1;

[0031] Figure 2 is an overlay of the GNSS velocity field map and the fault distribution map in specific embodiment 1;

[0032] Figure 3 According to the specific embodiment 1 Figure 1 Distribution of mid-station velocity relative to faults, set fault lines and target areas;

[0033] Figure 4 is a cross-fault crustal velocity profile diagram in specific embodiment 1, wherein Figure 4 (a) and (b) are Figure 3 The cross-fault crustal deformation information obtained by the velocity profile method in the middle section areas P1 and P2 includes the velocity variation across the fault, the slip rate of the fault, and the locking depth;

[0034] Figure 5 is an overlapping diagram of the InSAR velocity field map and the fault distribution map in specific embodiment 2;

[0035] Figure 6 According to the specific embodiment 2 Figure 2 Distribution of mid-station velocity relative to faults, set fault lines and target areas;

[0036] Figure 7 This is the cross-fault crust velocity profile diagram in specific embodiment 2, which uses the cross-fault crust deformation information obtained by the velocity profile method, including the velocity change across the fault, the slip rate of the fault and the locking depth. DETAILED DESCRIPTION

[0037] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0038] Example 1

[0039] This embodiment provides a cross-fault crustal deformation analysis method integrating GIS topology analysis technology, including the following steps:

[0040] Step 1: Obtain a crustal movement velocity field map and a fault distribution map, and overlap the crustal movement velocity field map and the fault distribution map to display the distribution of the stations in the crustal movement velocity field map relative to the fault distribution map;

[0041] In step 1, the crustal velocity field map contains discrete station velocities. There are two ways to represent station velocities: (1) Each station velocity is represented by two elements, a point and an arrow. The point represents the spatial location information (longitude and latitude) of the station, and the arrow represents the magnitude and direction of the velocity; (2) Each station velocity is represented by a point element. The position of the point represents the spatial location information of the station, and the color of the point represents the magnitude of the velocity. The fault distribution map contains discrete faults. Each fault is composed of one to multiple connected line elements. The line represents the spatial location information of the fault. Prepare the crustal velocity field map and the fault distribution map, that is, convert the station velocities and faults into spatial elements to store their information and display them separately. Overlay the crustal velocity field map and the fault distribution map, extract the station velocities from the crustal velocity field map and draw them on the faults in the fault distribution map, so as to show the distribution of the station velocities relative to the faults.

[0042] Step 2: According to the distribution of faults in step 1, set the target area and fault line and obtain the spatial position information of the fault line;

[0043] In step 2, the target region is a surface element representing the area for cross-fault crustal deformation analysis. The fault line is a line element representing the fault on which cross-fault crustal deformation analysis is performed and must be included in the target region. Set the target region and fault line required for cross-fault crustal deformation analysis based on the distribution of site velocities relative to the fault.

[0044] Step 3: Based on GIS topology analysis technology, determine the spatial relationship between the stations in the crustal movement velocity field map and the fault line in step 2 and the target area, and identify and extract the velocity field of the target area;

[0045] In step 3, GIS topology analysis is a method for processing and analyzing spatial elements (points, lines, and surfaces). Topology analysis can determine and manipulate the spatial relationships (adjacency, containment, and connectivity) between spatial elements. A containment relationship indicates that a point, line, or surface is completely contained within another surface. GIS topology analysis is used to determine the spatial relationship between the target area and the fault line. If the spatial relationship is a containment relationship, the next step is carried out. GIS topology analysis is also used to determine the spatial relationship between the target area and the stations in the crustal velocity field map. The velocities of the stations with a containment relationship are extracted and used to form the target area velocity field.

[0046] Step 4: Based on the spatial position information of the fault line in step 2, information on cross-fault crustal deformation is obtained using a cross-section method.

[0047] In step 4, the velocity profile is the relationship between the station velocity and its position relative to the fault line. Earth science velocity profiling methods quantify important fault closure and motion information. Based on the fault line location information (spatial position expressed in longitude and latitude) from step 2, the velocity profiling method is used to obtain cross-fault crustal deformation information, including cross-fault velocity variation, fault closure degree, and motion magnitude.

[0048] This example demonstrates a GNSS velocity field map within a crustal velocity field map. The data used is a GNSS velocity field map from 1991 to 2016, along with a fault distribution map of the Longmenshan thrust belt. The GNSS velocity field is derived from data from 2,403 GNSS stations. The fault distribution map of the Longmenshan thrust belt is developed based on geological surveys, seismic observations, and various geophysical data.

[0049] 1) First import the fault distribution map, then import the GNSS velocity field map and overlay it. Figure 2 shown

[0050] 2) Then, according to the distribution of faults, set the fault line. The fault line must be drawn along the fault distribution map and saved as the graphic element "F1". Figure 3 shown.

[0051] 3) According to the distribution of site velocity relative to the fault, set the target area. The target area must cross the fault line and ensure that site velocity exists on both sides of the fault line and is stored as the graphic element "P1". Figure 3 shown.

[0052] 4) Use the profile velocity method to calculate and output the cross-fault crust velocity variation map. The resulting map is shown in the attached figure. Figure 4 As shown in (a).

[0053] 5) Based on the cross-section drawn in step 4), repeat step 2) to draw a target area that is smaller than "P1" and save it as graphic element "P2". Figure 3 shown.

[0054] 6) Repeat the calculation and output of step 4). The resulting image is as shown in the attached figure. Figure 4 (b) shown.

[0055] Specifically, Figure 3 The fault lines and profiles are obtained by using a cross-fault crustal deformation analysis method that integrates GIS topological analysis technology provided by the present invention. Figure 4 The GNSS velocity profiles of the Longmenshan thrust belt are obtained by using a cross-fault crustal deformation analysis method integrated with GIS topological analysis technology provided by the present invention. (a) and (b) correspond to Figure 3P1 and P2 in . It can be seen that Figure 4 The cross-fault velocity profile of (b) is clearer, and the root mean square error between the fitted velocity and the measured velocity is smaller. Figure 4 The messy data on the left side of (a) improves the accuracy of the drawing.

[0056] Example 2

[0057] This embodiment differs from Example 1 in that Example 2 presents an InSAS velocity field map within the crustal velocity field map, using the InSAR velocity field map and fault distribution map of the northeastern Qinghai-Tibet Plateau from 2014 to 2016 as an example. The InSAR velocity field was calculated based on data collected by the Sentinel-1 satellite over the northeastern Qinghai-Tibet Plateau from 2014 to 2016, and the fault distribution map of the northeastern Qinghai-Tibet Plateau was developed based on geological surveys, seismic observations, and various geophysical exploration data.

[0058] 1) First import the fault distribution map, then import the InSAR velocity field map and overlay it. Figure 5 shown

[0059] 2) According to the distribution of faults, a fault line is set along a certain section of the original fault zone and saved as a graphic element. Figure 6 shown.

[0060] 3) According to the distribution of site velocity relative to the fault, set the target area. The target area must cross the fault line and ensure that site velocity exists on both sides of the fault line and is stored as a graphic element. Figure 6 shown.

[0061] 4) Use the profile velocity method to calculate and output the cross-fault crust velocity variation map. The resulting map is shown in the attached figure. Figure 7 shown.

[0062] Specifically, Figure 5 The fault lines and profiles are obtained by using a cross-fault crustal deformation analysis method that integrates GIS topological analysis technology provided by the present invention. Figure 6 This is an InSAR velocity profile of a section of a transoceanic fault zone, obtained using a cross-fault crustal deformation analysis method integrated with GIS topology analysis technology. Compared to GNSS velocity fields, InSAR velocity fields contain more station velocities, indicating more cross-fault crustal deformation information. This method allows for rapid and repeated extraction and analysis of deformation information within the fault zone.

[0063] In summary, the present invention provides a cross-fault crustal deformation analysis method that integrates GIS topological analysis technology. The method overlays a crustal velocity field map and a fault zone distribution map; sets a target area and fault lines; uses GIS topological analysis technology to determine the spatial relationship between the crustal velocity field, fault lines, and the target area, identifying and extracting the velocity field within the target area; and finally, obtains cross-fault crustal deformation information based on a velocity profile method. This method addresses the drawback of conventional velocity profile methods, which lack the ability to provide a "what you see is what you get" (WYSIWYG) results. It avoids the tedious process of repeatedly reviewing and editing data, effectively improving the efficiency and accuracy of cross-fault crustal deformation analysis.

[0064] Example 3

[0065] This embodiment provides a cross-fault crustal deformation analysis system using GIS topology analysis technology, including:

[0066] Module 1 is used to obtain a crustal movement velocity field map and a fault distribution map, and to overlap the crustal movement velocity field map and the fault distribution map to display the distribution of the stations in the crustal movement velocity field map relative to the fault distribution map;

[0067] Module 2 is used to set the target area and fault line according to the distribution of faults and obtain the spatial position information of the fault line;

[0068] Module 3 is used to determine the spatial relationship between the stations and fault lines in the crustal movement velocity field map and the target area based on GIS topological analysis technology, and to identify and extract the velocity field of the target area;

[0069] Module 4 is used to obtain information on cross-fault crustal deformation based on the spatial position information of the fault line and the cross-fault method.

[0070] It should be understood that parts not elaborated in detail in this specification belong to the prior art.

[0071] It should be understood that the above description of the preferred embodiments is relatively detailed and cannot be considered as limiting the scope of protection of the present invention. It is not necessary and impossible to list all embodiments here. Under the guidance of the present invention, ordinary technicians in this field can also make substitutions or modifications without departing from the scope of protection of the claims of the present invention, which fall within the scope of protection of the present invention. The scope of protection of the present invention shall be based on the attached claims.

Claims

1. A cross-fault crustal deformation analysis method integrating GIS topological analysis technology, characterized in that: The following steps are involved: Step 1: Obtain a crustal movement velocity field map and a fault distribution map, and overlap the crustal movement velocity field map and the fault distribution map to display the distribution of the stations in the crustal movement velocity field map relative to the fault distribution map; Step 2: According to the distribution of faults in step 1, set the target area and fault line and obtain the spatial position information of the fault line; Step 3: Based on GIS topology analysis technology, determine the spatial relationship between the stations in the crustal movement velocity field map and the fault line in step 2 and the target area, and identify and extract the velocity field of the target area; Step 4: Based on the spatial position information of the fault line in step 2, information on cross-fault crustal deformation is obtained using a cross-section method.

2. The cross-fault crustal deformation analysis method integrating GIS topology analysis technology according to claim 1 is characterized in that: The crustal movement velocity field map in step 1 includes discrete site spatial location information and the velocity magnitude and direction at each crustal movement site. The site velocity magnitude and direction are converted into spatial elements to store their information and are displayed in maps respectively.

3. According to the method of claim 2, the cross-fault crustal deformation branching line elements integrated with GIS topological analysis technology are composed of lines representing the spatial position information of the fault, and the fault is converted into a spatial element to store its information and display it in a graph respectively.

4. The cross-fault crustal deformation analysis method integrating GIS topology analysis technology according to claim 2 is characterized by: The crustal movement velocity field map and the fault distribution map are overlapped, and the site velocity in the crustal movement velocity field map is extracted and plotted on the fault in the fault distribution map, thereby showing the distribution of the site velocity relative to the fault.

5. The cross-fault crustal deformation analysis method integrating GIS topology analysis technology according to claim 1 is characterized in that: The target area set in step 2 is a surface element, which represents the regional range for cross-fault crustal deformation analysis; the fault line is a line element, which represents the fault for cross-fault crustal deformation analysis and is included in the target area; according to the distribution of site velocity relative to the fault, the target area and fault line required for cross-fault crustal deformation analysis are set and the spatial position information of the fault line is obtained.

6. The cross-fault crustal deformation analysis method integrating GIS topology analysis technology according to claim 1 is characterized in that: In step 3, GIS topology analysis technology is used to determine the spatial relationship between the target area and the fault line. If the spatial relationship is a containment relationship, the next step is performed; GIS topology analysis technology is used to determine the spatial relationship between the target area and the stations in the crustal movement velocity field map, and the velocities of the stations with a containment relationship are extracted to form the target area velocity field.

7. The cross-fault crustal deformation analysis method integrating GIS topology analysis technology according to claim 1 is characterized in that: In step 4, the spatial position information of the fault line in step 2 is used, and the important closure and movement information of the fault is quantitatively calculated based on the velocity profile method to obtain cross-fault crustal deformation information, including the cross-fault velocity variation diagram, the closure degree of the fault, and the movement size.

8. A cross-fault crustal deformation analysis system integrating GIS topological analysis technology, characterized in that: include: Module 1 is used to obtain a crustal movement velocity field map and a fault distribution map, and to overlap the crustal movement velocity field map and the fault distribution map to display the distribution of the stations in the crustal movement velocity field map relative to the fault distribution map; Module 2 is used to set the target area and fault line according to the distribution of faults and obtain the spatial position information of the fault line; Module 3 is used to determine the spatial relationship between the stations and fault lines in the crustal movement velocity field map and the target area based on GIS topological analysis technology, and to identify and extract the velocity field of the target area; Module 4 is used to obtain information on cross-fault crustal deformation based on the spatial position information of the fault line using a cross-section method; The cross-fault crustal deformation analysis system integrating GIS topology analysis technology is used to execute the steps in the cross-fault crustal deformation analysis method integrating GIS topology analysis technology described in any one of claims 1-7.

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