Earthquake hazard assessment method and system based on fault inter-earthquake sliding inversion

Abstract

The invention discloses an earthquake hazard assessment method and system based on fault inter-earthquake sliding inversion, and relates to the technical field of earthquake assessment, and the method comprises the steps: obtaining a high-resolution surface line-of-sight velocity diagram of a sliding fault in an inter-earthquake period, and obtaining a fault surface trace through the surface line-of-sight velocity diagram; determining a triangular dislocation model of the shallow fault based on the fault surface trace, performing vertical projection on nodes of the shallow fault to obtain a deep rectangular model, and combining the triangular dislocation model and the deep rectangular model to obtain a deep and shallow fault model; carrying out fault slip distribution inversion by combining an InSAR earth surface deformation result with a triangular dislocation model, estimating the slip amount on each dislocation element, and obtaining a seismic moment accumulation rate and a seismic moment; the earthquake repetition time of the fault is obtained through the accumulated earthquake moment and the historical earthquake magnitude, and the earthquake risk of each fault section is evaluated. According to the invention, the seismic moment accumulation rate and the seismic moment are directly obtained, and the accuracy of earthquake risk assessment is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of earthquake assessment, and in particular to an earthquake hazard assessment method and system for fault interseismic slip inversion. Background Art

[0002] Active faults are geological structural features that are widely present around the world. The dynamic behavior of these faults directly affects the regional seismic activity and earthquake disaster risk. Research on the deformation characteristics of active faults not only helps to understand the deformation mechanism of the lithosphere, but also provides important support for judging the regional earthquake hazard.

[0003] In recent years, with the development of satellite observation technology, especially the application of synthetic aperture radar interferometry (InSAR), high-resolution observation of fault surface deformation has become possible, thus providing data support for the dynamic study of slip faults during the interseismic period.

[0004] However, traditional modeling methods are limited by the complexity of fault geometry. It is difficult to accurately characterize the spatiotemporal evolution characteristics of slip faults using a rectangular dislocation model. In previous studies on determining regional seismic hazards, it is usually difficult to obtain the fault structure loading rate, resulting in unclear fault analysis results, which in turn affects the accuracy of fault slip distribution and seismic hazard assessment. Summary of the invention

[0005] The purpose of the present invention is to address the deficiencies of the above-mentioned prior art and to provide a method and system for earthquake hazard assessment based on interseismic fault slip inversion, so as to solve the problem that the prior art is limited by the complexity of fault geometry and it is difficult to accurately characterize the spatiotemporal evolution characteristics of slip faults using a rectangular dislocation model. In previous studies on judging regional earthquake hazard, it is usually difficult to obtain the fault structure loading rate, resulting in unclear fault analysis results, which in turn affects the accuracy of fault slip distribution and earthquake hazard assessment.

[0006] The present invention specifically provides the following technical solutions:

[0007] A method for earthquake hazard assessment based on fault interseismic slip inversion comprises the following steps:

[0008] Obtain the surface line-of-sight velocity map of the slip fault in the target area during the interseismic period, and obtain the surface trace of the fault through the surface line-of-sight velocity map;

[0009] Determine the triangular dislocation model of the shallow fault based on the surface trace of the fault, and vertically project the nodes of the shallow fault to obtain a deep rectangular model, and combine the triangular dislocation model and the deep rectangular model to obtain a deep and shallow dislocation model; wherein the shallow part is a triangular element and the deep part is a rectangular element;

[0010] Obtain the InSAR surface deformation results in the target area, and perform fault slip distribution inversion with the deep and shallow dislocation models, estimate the slip amount on each dislocation element, and based on the slip amount, integrate the seismic moment accumulation rate of the sub-fault along the dip direction of the shallow fault plane to obtain the seismic moment accumulation rate along the fault strike, and assume that the last earthquake completely released the seismic moment accumulated in the previous earthquake cycle, and obtain the cumulative seismic moment of the fault since the last earthquake through the seismic moment accumulation rate and accumulation time;

[0011] By accumulating seismic moments and assuming that an earthquake of the same magnitude as the last major earthquake will occur on the fault, the earthquake repetition time of the fault is obtained and the seismic hazard of each fault segment is evaluated.

[0012] Preferably, based on the slip amount, the seismic moment accumulation rate of the sub-fault along the dip direction of the shallow fault plane is integrated to obtain the seismic moment accumulation rate along the fault strike, including:

[0013] Based on the slip between shallow and deep earthquakes, the seismic moment accumulation rate is calculated by integrating the slip rate loss of each sub-fault along the fault strike. The specific expression is:

[0014] M0=G∑ i |V d -V i |S i ;

[0015] Where M0 is the earthquake moment accumulation rate, G is the shear modulus, V d represents the slip rate of the deep fault, V i With S i They represent the slip rate and area of ​​the shallow fault respectively, and i is the serial number of the shallow sub-fault.

[0016] Preferably, when assuming that the last earthquake completely released the seismic moment accumulated in the last earthquake cycle, the accumulated seismic moment of the fault since the last earthquake is obtained by the seismic moment accumulation rate and the accumulation time. The specific expression is:

[0017]

[0018] Among them, M w is the seismic moment, T n is the current time, T l The time when the most recent earthquake occurred.

[0019] Preferably, when obtaining the earthquake recurrence time of the fault and evaluating the seismic hazard of each fault segment, sub-faults with a short recurrence interval and a seismic moment accumulation rate higher than a threshold are regarded as areas with earthquake risks.

[0020] Preferably, determining a triangular dislocation model of a shallow fault based on the fault surface trace comprises:

[0021] Horizontal sampling is performed at preset intervals on the determined surface trace, and vertical sampling is performed along the depth of the fault in the direction of the fault dip;

[0022] An irregular triangular network is used to connect the horizontal and vertical sampled vertices to form a triangular dislocation model of a shallow fault, and triangular dislocation models with different inclination angles are generated; the optimal inclination angle is determined by minimizing the data fitting error.

[0023] Preferably, the step of obtaining a surface line-of-sight velocity map of a slip fault in a target area during an interseismic period includes:

[0024] Acquire SAR images within the target area;

[0025] A short-time interferogram is generated by using SAR images whose time baseline is less than a short threshold number of days, and a long-time interferogram is generated by using SAR images whose time baseline is less than a long threshold number of days; wherein the short threshold value represents a threshold value less than a set number of days, and the long threshold value represents a threshold value greater than a set number of days;

[0026] The atmospheric phase effect in the short-time interferogram and the long-time interferogram is removed to obtain the interferogram with quality higher than the threshold. The InSAR stacking algorithm is used to obtain the surface line-of-sight velocity map of the slip fault during the interseismic period in the interferogram with quality higher than the threshold.

[0027] The present invention provides an earthquake hazard assessment system for fault interseismic slip inversion, comprising:

[0028] An acquisition module is used to obtain a surface line-of-sight velocity map of a slip fault in a target area during an interseismic period, and to obtain a surface trace of the fault through the surface line-of-sight velocity map;

[0029] A model building module is used to determine the triangular dislocation model of the shallow fault based on the surface trace of the fault, and vertically project the nodes of the shallow fault to obtain a deep rectangular model, and combine the triangular dislocation model and the deep rectangular model to obtain a deep and shallow dislocation model; wherein the shallow part is a triangular element and the deep part is a rectangular element;

[0030] An inversion module is used to obtain the InSAR surface deformation results in the target area, and perform fault slip distribution inversion with the deep and shallow dislocation models, estimate the slip amount on each dislocation element, and based on the slip amount, integrate the seismic moment accumulation rate of the sub-fault along the dip direction of the shallow fault plane to obtain the seismic moment accumulation rate along the fault strike, and assume that the last earthquake completely released the seismic moment accumulated in the previous earthquake cycle, and obtain the accumulated seismic moment of the fault since the last earthquake through the seismic moment accumulation rate and accumulation time;

[0031] The evaluation module is used to obtain the earthquake repetition time of the fault by accumulating seismic moments and assuming that an earthquake with the same magnitude as the last large earthquake will occur on the fault, and to evaluate the seismic hazard of each fault segment.

[0032] The present invention provides a computer device, including a memory and a processor, wherein a program is stored in the memory, and when the program is executed by the processor, the processor executes the steps of the above-mentioned earthquake hazard assessment method of fault interseismic slip inversion.

[0033] The present invention provides a storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of the earthquake hazard assessment method of fault interseismic slip inversion are implemented.

[0034] Compared with the prior art, the present invention has the following significant advantages:

[0035] The present invention determines the surface trace of the fault, the triangular dislocation model and the deep rectangular model of the shallow fault, and directly constructs a dislocation model that is variable along the fault direction, thereby solving the problem that the traditional rectangular dislocation model is difficult to construct with geometric complexity. At the same time, the fault slip distribution is inverted through the InSAR surface deformation results and the dislocation model, and the seismic moment accumulation rate and the seismic moment are directly obtained, thereby solving the problem that it is difficult to obtain the loading rate of the seismic fault structure and improving the accuracy of the fault slip distribution and the earthquake hazard assessment. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is the structural background map of the Middle East Anatolian Fault System of the present invention; wherein, Figure 1 (a) Spatial distribution of the Anatolian Block and historical earthquakes; the red and blue boxes and track numbers show the area covered by Sentinel-1A / B, the black arrows indicate the horizontal velocity field, the red stars indicate earthquakes with a magnitude greater than 7, the black lines represent the fault strikes of the NAF and EAF, and the black rectangular boxes show Figure 1 (b) shows the location of the study area, Figure 1 (b) EAF map displayed in the Oblique Mercator projection, with black beach balls marking earthquakes that have occurred since 2020, solid grey lines representing fault maps from the GEM Global Active Fault Project, and cyan triangles marking city locations. Figure 1 (c) A compilation of geodetic and geological slip rates along the EAF segment from Sivrice to K1rikhan;

[0037] Figure 2 The blue dots represent the standard deviation of the unwrapped phase before and after the GACOS correction. Figure 2(a) Schematic diagram showing that the standard deviation without GACOS correction is larger than the standard deviation after GACOS correction. Figure 2 (b) and Figure 2 (c) The standard deviation of DSC 021 and 123 orbits, Figure 2 (d) Figure 2 (e) and Figure 2 (f) Standard deviation variation diagrams for ASC 014, ASC 116, and ASC 043 tracks, respectively;

[0038] Figure 3 Interseismic surface velocity maps of observed values ​​(first column), simulated values ​​(second column) and residual values ​​(third column) in the present invention, from ASC and DSC Sentinel-1A / B tracks; purple triangles indicate reference pixels of InSAR results, black lines indicate fault surface strikes used in the present invention; positive values ​​indicate motion toward the satellite; Figure 3 (a) Figure 3 (b) and Figure 3 (c) ASC 014, ASC 116, and ASC 043 tracks, respectively; Figure 3 (d) Figure 3 (e) and Figure 3 (f) DSC 021 and ASC 123 tracks, respectively, Figure 3 (c) with Figure 3 The histogram in (f) shows the residuals of the fitted Gaussian curve;

[0039] Figure 4 It is the interseismic slip model diagram inverted by using ASC and DSC Sentinel-1A / B velocity diagrams in the present invention; Figure 4 (a) and Figure 4 (b) The geometric structures of the shallow and deep dislocation models, respectively. Figure 4 (a1), Figure 4 (a2), Figure 4 (a3) and Figure 4 (a4) are the inverted interseismic shallow slip models, Figure 4 (b1), Figure 4 (b2), Figure 4 (b3) and Figure 4 (b4) are the inverted interseismic deep slip models, black stars indicate historical earthquakes with magnitude greater than 6.8, and the coordinate system is UTM 37S zone;

[0040] Figure 5 The estimated seismic moment loss rate along the EAF in this invention and the cumulative seismic moment since the last major earthquake are shown in Figure 2; "S" represents the fault segment, Figure 5(a) Fault segmentation and historical earthquakes. Black beach balls represent earthquakes that have occurred since 2020, and red stars represent historical earthquakes. Figure 5 (b) the approximate rupture extent and timing of the most recent major earthquake on each fault segment, Figure 5 (c) the current seismic moment loss rate, Figure 5 (d) the accumulated seismic moment since the last major earthquake;

[0041] Figure 6 The present invention provides a flow chart of a method for earthquake hazard assessment based on interseismic fault slip inversion. DETAILED DESCRIPTION

[0042] The following is a clear and complete description of the technical solutions of the embodiments of the present invention in conjunction with the drawings in the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0043] like Figure 6 As shown, the present invention provides a method for earthquake hazard assessment based on fault interseismic slip inversion, which specifically includes the following steps:

[0044] Step S1: Obtain a high-resolution surface line-of-sight velocity map of the slip fault in the target area during the interseismic period, wherein high resolution means that its spatial resolution is higher than a set threshold, and obtain the fault surface trace through the surface line-of-sight velocity map.

[0045] Obtain high-resolution surface directional velocity maps of slip faults during interseismic periods, including:

[0046] In order to ensure coherence and accuracy, the long and short baseline interferometry strategy is used to obtain the interferometric radar InSAR time series and obtain SAR images.

[0047] A short-term interferogram is generated by using SAR images with a time baseline less than a short threshold number of days (90 days in this embodiment), and a long-term interferogram is generated by using SAR images with a time baseline less than a long threshold number of days (365-405 days in this embodiment) in order to limit the possible phase deviation in the short-term interferogram. The short threshold value represents a threshold value less than the set number of days, and the long threshold value represents a threshold value greater than the set number of days.

[0048] The atmospheric phase effect in short-time and long-time interferograms is estimated and removed by the InSAR General Atmospheric Correction Online Service (GACOS). The interferograms with quality higher than the threshold are selected through visual interpretation. The InSAR stacking algorithm is used to obtain high-resolution surface line-of-sight (LOS) velocity maps of the slip fault during the interseismic period from the interferograms with quality higher than the threshold.

[0049] The surface traces of faults are determined based on the high-resolution surface deformation field during the interseismic period (composed of high-resolution surface line-of-sight (LOS) velocity maps), historical earthquake data, and historical fault database information (GEM).

[0050] Step S2: Determine the triangular dislocation model of the shallow fault based on the surface trace of the fault, and vertically project the nodes of the shallow fault to obtain a deep rectangular model, and combine the triangular dislocation model and the deep rectangular model to obtain a deep and shallow dislocation model; wherein the shallow part is a triangular element and the deep part is a rectangular element.

[0051] Based on the determined fault surface trace, a triangular dislocation model of the shallow fault plane (0-30 km depth) is determined to fit the near-field deformation signal.

[0052] Among them, the triangular dislocation model of shallow faults (0-30 km depth) is determined based on the fault surface trace, which is used to fit the near-field deformation signal, including:

[0053] Horizontal sampling is performed at a preset (b km (3 km in this embodiment)) spacing on the determined surface trace, and vertical sampling is performed along the depth of the fault in the inclination direction of the fault. The sampling spacing increases from about 3 km at the surface to about 5 km at a depth of 30 km.

[0054] The horizontal and vertical sampled vertices are connected by using irregular triangulated network (TIN) to form a triangular dislocation model of shallow faults. Triangular dislocation models with different inclination angles are generated and the optimal inclination angle is determined by minimizing the data fitting error.

[0055] The deep fault plane (30-1000 km depth) is composed of vertical rectangular dislocations and is used to fit the far-field deformation signal. Specific operation: The nodes at the depth of 30 km of the shallow fault are vertically projected to the depth of 1000 km to form a deep rectangular model.

[0056] Step S3: Taking the InSAR surface deformation results in the target area as constraints, the fault slip distribution inversion is performed in combination with the shallow dislocation model with deep position, and the slip amount on each dislocation element is estimated using the constrained least squares method. Based on the slip amount, the seismic moment accumulation rate of the sub-fault along the dip direction of the shallow fault plane is integrated to obtain the seismic moment accumulation rate (MDR) along the fault strike. Assuming that the last earthquake completely released the seismic moment accumulated in the previous earthquake cycle, the accumulated seismic moment of the fault since the last earthquake is obtained through the seismic moment accumulation rate and the accumulation time.

[0057] Before obtaining the InSAR surface deformation results, it also includes: considering the density and high spatial coherence of the InSAR deformation rate result points, the InSAR surface deformation results are downsampled according to the distance between the displacement field and the fault, so that the near-field data points are dense and the far-field data points are sparse.

[0058] Based on the slip amount, the seismic moment accumulation rate of the sub-fault along the dip direction of the shallow fault plane is integrated to obtain the seismic moment accumulation rate along the fault strike, including:

[0059] Based on the slip amount (slip distribution) between shallow and deep earthquakes, the seismic moment accumulation rate is calculated by integrating the slip rate loss of each sub-fault along the fault strike. The specific expression is:

[0060] M0=G∑ i |V d -V i |S i ;

[0061] Where M0 is the seismic moment accumulation rate (valued at 35 GPa), G is the shear modulus, V d represents the slip rate of the deep fault, V i With S i They represent the slip rate and area of ​​the shallow fault, respectively, and i is the number of the shallow sub-fault. Low MDR values ​​usually indicate a creep zone with no significant strain accumulation, while high MDR values ​​indicate significant strain accumulation and a possible high earthquake risk.

[0062] Combined with historical earthquake records, the accumulated seismic moment of each sub-fault since the nearest major earthquake is obtained to evaluate the earthquake potential. That is, assuming that the last earthquake completely released the accumulated seismic moment of the previous earthquake cycle, the accumulated seismic moment of the fault since the last earthquake is obtained through the seismic moment accumulation rate and accumulation time. The specific expression is:

[0063]

[0064] Among them, M w is the seismic moment, T n is the current time, T l The time when the most recent earthquake occurred.

[0065] Step S4: By accumulating seismic moments and assuming that an earthquake with the same magnitude as the last major earthquake will occur on the fault, the earthquake repetition time of the fault is obtained, and the seismic hazard of each fault segment is evaluated.

[0066] Assuming that each fault segment experiences an earthquake of the same magnitude as the last major earthquake, the recurrence interval of each fault segment can be estimated by accumulating seismic moments and the magnitude of historical earthquakes. When obtaining the seismic hazard of each fault segment through the recurrence interval, the sub-faults with short recurrence intervals and seismic moment accumulation rates MDR above the threshold are regarded as areas with seismic risks. This area indicates a high seismic risk, and the accumulated strain energy may trigger a major earthquake in the future. In this way, the seismic hazard of each section of the fault zone is systematically, comprehensively and quantitatively evaluated, providing a data basis for predicting future seismic activities.

[0067] Based on the above method, the present invention provides an earthquake hazard assessment system for fault interseismic slip inversion, comprising: an acquisition module, a model building module, an inversion module and an assessment module.

[0068] Among them, the acquisition module is used to obtain the surface line-of-sight velocity map of the slip fault during the interseismic period and obtain the surface trace of the fault; the model construction module is used to determine the dislocation model of the shallow fault based on the surface trace of the fault, and vertically project the nodes of the shallow fault to a km deep to obtain a deep rectangular model; the shallow part is a triangular element and the deep part is a rectangular element; the inversion module is used to obtain the InSAR surface deformation results, and perform fault slip distribution inversion with the dislocation model to estimate the slip amount on each dislocation element, and obtain the seismic moment accumulation rate along the fault strike by integrating the seismic moment accumulation rate of the sub-fault along the dip direction of the shallow fault plane, and obtain the cumulative seismic moment of the fault since the last earthquake when the last earthquake completely released the seismic moment accumulated in the previous earthquake cycle; the evaluation module is used to obtain the earthquake repetition time of the fault through the accumulated seismic moment and assume that an earthquake of the same magnitude as the last major earthquake will occur on the fault, and evaluate the seismic hazard of each fault segment.

[0069] The present invention also provides a computer device, including a memory and a processor, wherein a program is stored in the memory, and when the program is executed by the processor, the processor executes the steps of an earthquake hazard assessment method of fault interseismic slip inversion.

[0070] In accordance with the disclosed embodiments, a computing device may communicate with one or more external devices (e.g., keyboards, pointing devices, Bluetooth communications, etc.), or with any device (e.g., routers, modems, etc.) that enables a computing device to communicate with one or more other computing devices.

[0071] The present invention also provides a storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of a method for earthquake hazard assessment based on interseismic fault slip inversion are implemented.

[0072] According to the disclosed embodiments, the storage medium may be a non-volatile computer-readable storage medium, such as but not limited to: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present invention, the storage medium may be any tangible medium containing or storing a program that may be used by or in conjunction with an instruction execution system, apparatus, or device.

[0073] like Figure 1 to Figure 5 The research results shown in the figure show that the accurate inversion of the slip distribution and strain accumulation characteristics of the deep and shallow parts of the slip fault during the interseismic period reveals that the slip rate of the entire EAF has spatial heterogeneity (the strike and dip direction of the fault plane). Figure 1 In (b), 1 is 1874M7.1, 2 is 2020M6.7, 3 is 1875M6.7, 4 is 1893M7.1, 5 is 1513M7.4, 6 is 1822M7.5, and 7 is 1544M6.7. Figure 3 The μ and σ in represent the mean and standard deviation of Gaussian distribution respectively.

[0074] For the first time, the dynamic evolution of different fault segments of the EAF was systematically characterized. The high slip loss of the Palu fault segment indicates that it has a higher earthquake risk. The research results provide new insights into the understanding of the dynamic behavior of the EAF and its earthquake risk assessment.

[0075] This method is not only applicable to specific slip faults, but also to slip faults with complex geometric characteristics around the world, providing important technical support for earthquake early warning and disaster prevention.

[0076] The above content is a further detailed description of the present invention in combination with a specific preferred embodiment. For technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as belonging to the protection scope of the present invention.

Claims

1. A method for earthquake hazard assessment based on interseismic fault slip inversion, characterized in that: The steps include: Obtain the surface line-of-sight velocity map of the slip fault in the target area during the interseismic period, and obtain the surface trace of the fault through the surface line-of-sight velocity map; Determine the triangular dislocation model of the shallow fault based on the surface trace of the fault, and vertically project the nodes of the shallow fault to obtain a deep rectangular model, and combine the triangular dislocation model and the deep rectangular model to obtain a deep and shallow dislocation model; wherein the shallow part is a triangular element and the deep part is a rectangular element; Obtain the InSAR surface deformation results in the target area, and perform fault slip distribution inversion with the deep and shallow dislocation models, estimate the slip amount on each dislocation element, and based on the slip amount, integrate the seismic moment accumulation rate of the sub-fault along the dip direction of the shallow fault plane to obtain the seismic moment accumulation rate along the fault strike, and assume that the last earthquake completely released the seismic moment accumulated in the previous earthquake cycle, and obtain the cumulative seismic moment of the fault since the last earthquake through the seismic moment accumulation rate and accumulation time; By accumulating seismic moments and assuming that an earthquake of the same magnitude as the last major earthquake will occur on the fault, the earthquake repetition time of the fault is obtained and the seismic hazard of each fault segment is evaluated.

2. A method for earthquake hazard assessment based on fault interseismic slip inversion as claimed in claim 1, characterized in that: Based on the slip amount, the seismic moment accumulation rate of the sub-fault along the dip direction of the shallow fault plane is integrated to obtain the seismic moment accumulation rate along the fault strike, including: Based on the slip between shallow and deep earthquakes, the seismic moment accumulation rate is calculated by integrating the slip rate of each sub-fault along the fault strike. The specific expression is: M0=G∑ i |V d -V i |S i ; Where M0 is the earthquake moment accumulation rate, G is the shear modulus, V d represents the slip rate of the deep fault, V i With S i They represent the slip rate and area of ​​the shallow fault respectively, and i is the serial number of the shallow sub-fault.

3. A method for earthquake hazard assessment based on fault interseismic slip inversion as claimed in claim 2, characterized in that: Assuming that the last earthquake completely released the seismic moment accumulated in the last earthquake cycle, the accumulated seismic moment of the fault since the last earthquake is obtained by the seismic moment accumulation rate and accumulation time. The specific expression is: Among them, M w is the seismic moment, T n is the current time, T l The time when the most recent earthquake occurred.

4. The earthquake hazard assessment method of fault interseismic slip inversion according to claim 1, characterized in that: When obtaining the earthquake repetition time of the fault and evaluating the earthquake hazard of each fault segment, the sub-faults with a short recurrence interval and an earthquake moment accumulation rate higher than a threshold are regarded as areas with earthquake risks.

5. The earthquake hazard assessment method of fault interseismic slip inversion according to claim 1, characterized in that: Determining a triangular dislocation model of a shallow fault based on the fault surface trace includes: Horizontal sampling is performed at preset intervals on the determined surface trace, and vertical sampling is performed along the depth of the fault in the direction of the fault dip; An irregular triangular network is used to connect the horizontal and vertical sampled vertices to form a triangular dislocation model of a shallow fault, and triangular dislocation models with different inclination angles are generated; the optimal inclination angle is determined by minimizing the data fitting error.

6. The earthquake hazard assessment method of fault interseismic slip inversion according to claim 1, characterized in that: The method of obtaining a surface line-of-sight velocity map of a slip fault in a target area during an interseismic period includes: Acquire SAR images within the target area; A short-time interferogram is generated by using SAR images whose time baseline is less than a short threshold number of days, and a long-time interferogram is generated by using SAR images whose time baseline is less than a long threshold number of days; wherein the short threshold value represents a threshold value less than a set number of days, and the long threshold value represents a threshold value greater than a set number of days; The atmospheric phase effect in the short-time interferogram and the long-time interferogram is removed to obtain the interferogram with quality higher than the threshold. The InSAR stacking algorithm is used to obtain the surface line-of-sight velocity map of the slip fault during the interseismic period in the interferogram with quality higher than the threshold.

7. A seismic hazard assessment system for fault interseismic slip inversion, characterized in that: include: An acquisition module is used to obtain a surface line-of-sight velocity map of a slip fault in a target area during an interseismic period, and to obtain a surface trace of the fault through the surface line-of-sight velocity map; A model building module is used to determine the triangular dislocation model of the shallow fault based on the surface trace of the fault, and vertically project the nodes of the shallow fault to obtain a deep rectangular model, and combine the triangular dislocation model and the deep rectangular model to obtain a deep and shallow dislocation model; wherein the shallow part is a triangular element and the deep part is a rectangular element; An inversion module is used to obtain the InSAR surface deformation results in the target area, and perform fault slip distribution inversion with the deep and shallow dislocation models, estimate the slip amount on each dislocation element, and based on the slip amount, integrate the seismic moment accumulation rate of the sub-fault along the dip direction of the shallow fault plane to obtain the seismic moment accumulation rate along the fault strike, and assume that the last earthquake completely released the seismic moment accumulated in the previous earthquake cycle, and obtain the accumulated seismic moment of the fault since the last earthquake through the seismic moment accumulation rate and accumulation time; The evaluation module is used to obtain the earthquake repetition time of the fault by accumulating seismic moments and assuming that an earthquake with the same magnitude as the last large earthquake will occur on the fault, and to evaluate the seismic hazard of each fault segment.

8. A computer device, characterized in that: It comprises a memory and a processor, wherein the memory stores a program, and when the program is executed by the processor, the processor executes the steps of a method for earthquake hazard assessment of interseismic fault slip inversion as described in any one of claims 1 to 6.

9. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of a method for earthquake hazard assessment based on interseismic fault slip inversion according to any one of claims 1 to 6 are implemented.

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