Regional earthquake early warning magnitude rapid estimation method

Abstract

The invention discloses a regional earthquake early warning magnitude rapid estimation method, which belongs to the technical field of magnitude estimation, and comprises the following steps of: calculating a first report estimation magnitude of a first trigger station based on a gauge function, a maximum motion amplitude, an epicentral distance and a magnitude correction value of the first trigger station; calculating the estimated magnitude of each trigger station at the t moment based on the gauge function of each trigger station, the maximum motion amplitude at the t moment, and the epicentral distance and magnitude correction value at the t moment; fusing the estimated magnitude of each trigger station at the t moment by using the weight of each trigger station at the t moment to obtain a fused magnitude at the t moment; and if the fused magnitude at the moment t is greater than a preset threshold value, correcting the fused magnitude at the moment t by using the intensity magnitude to obtain a final estimated magnitude at the moment t. According to the invention, the accuracy, stability and timeliness of magnitude estimation in regional early warning application can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of magnitude estimation, in particular to a regional earthquake early warning magnitude rapid estimation method. BACKGROUND

[0002] At present, the domestic earthquake early warning system has generally adopted a magnitude rapid estimation method based on the initial characteristics of P waves. By constructing an empirical gauge function between parameters such as Pd and τc and the epicentral distance Δ, combined with station correction, the magnitude estimation is realized, and it plays an important role in disaster prevention and mitigation of major projects such as railways, oil and gas pipelines, and urban rail transit. The national earthquake intensity rapid reporting and early warning project has also built an earthquake observation network covering the whole country with real-time data exchange capability, especially in key areas such as high-speed rail and pipelines, which has laid a data foundation for rapid magnitude determination. However, the existing magnitude estimation method still has significant limitations in regional engineering applications: the gauge function is mostly based on national or external regional data, which may lead to systematic underestimation in local near-field events; the observation bias caused by differences in site conditions and instrument response of different types of stations is not considered; the traditional ML magnitude has saturation phenomenon under the condition of moderate-strong earthquakes, and lacks compensation mechanism of joint intensity parameters; and the existing method mostly relies on single station fixed value, lacks multi-station fusion and time evolution mechanism, resulting in large fluctuation and poor stability of magnitude estimation. Therefore, how to provide a regional earthquake early warning magnitude rapid estimation method which can improve the accuracy, stability and timeliness of magnitude estimation in regional early warning application is a problem to be solved by those skilled in the art. SUMMARY

[0003] Therefore, the purpose of the present application is to provide a regional earthquake early warning magnitude rapid estimation method.

[0004] In order to achieve the above purpose, the present application adopts the following technical solutions: A regional earthquake early warning magnitude rapid estimation method, comprising the following steps: Obtaining the maximum ground motion amplitude, epicentral distance, station type and magnitude correction value of the first triggered station in the selected region when an earthquake occurs; wherein the station type includes reference station and general station; Obtaining the gauge function of the first triggered station based on the station type and epicentral distance of the first triggered station; Based on the gauge function, maximum ground motion amplitude, epicentral distance and magnitude correction value of the first triggered station, calculating the first report estimated magnitude of the first triggered station; Obtaining the maximum ground motion amplitude, epicentral distance, station type and magnitude correction value of each triggered station at time t; wherein t is a certain time after the earthquake occurs; The gauge function of each triggering station is obtained based on the station type and epicentral distance at time t. Based on the gauge function of each triggering station, the maximum ground motion amplitude at time t, the epicentral distance at time t, and the magnitude correction value, the estimated magnitude of each triggering station at time t is calculated. The estimated magnitudes of each triggering station at time t are fused using the weights of each triggering station at time t to obtain the fused magnitude at time t. If the merged magnitude at time t is greater than a preset threshold, the merged magnitude at time t is corrected using the intensity magnitude to obtain the final estimated magnitude at time t.

[0005] Preferably, the rapid estimation method further includes the following steps: constructing several gauge functions based on the station type of each station in the selected area and the relevant parameters of the historical earthquake events in which each station participated; wherein, the relevant parameters include epicentral distance and maximum ground motion amplitude; the several gauge functions include a benchmark station gauge function with an epicentral distance less than a preset threshold, a benchmark station gauge function with an epicentral distance greater than or equal to a preset threshold, a general station gauge function with an epicentral distance less than a preset threshold, and a general station gauge function with an epicentral distance greater than or equal to a preset threshold; The magnitude correction values ​​for each station within the selected area are calculated based on the estimated magnitude and actual reference magnitude of historical earthquake events involving each station within the selected area.

[0006] Preferably, the aforementioned gauge functions are constructed based on the following steps: Obtain relevant parameters of the first type of historical earthquake events involving each reference station in the selected area, wherein the relevant parameters include epicentral distance and maximum ground motion amplitude, and the first type of historical earthquake events are historical earthquake events with an epicentral distance less than a preset threshold; After substituting the relevant parameters of the first type of historical earthquake events in which each base station participated into the magnitude estimation model, the least squares method was used to fit the model to obtain the base station gauge function for the epicentral distance being less than the preset threshold. Obtain relevant parameters of the second type of historical earthquake events involving each reference station in the selected area. The relevant parameters include epicentral distance and maximum ground motion amplitude. The second type of historical earthquake events are historical earthquake events with an epicentral distance greater than or equal to a preset threshold. After substituting the relevant parameters of the second type of historical earthquake events in which each base station participated into the magnitude estimation model, the least squares method was used to fit the model to obtain the base station gauge function with the epicentral distance greater than or equal to the preset threshold. Obtain relevant parameters of the first type of historical earthquake events involving various general stations within the selected area. The relevant parameters include epicentral distance and maximum ground motion amplitude. The first type of historical earthquake events are historical earthquake events with an epicentral distance less than a preset threshold. After substituting the relevant parameters of the first type of historical earthquake events in which each general station participated into the magnitude estimation model, the least squares method was used to fit the model to obtain the general station gauge function where the epicentral distance is less than the preset threshold. Obtain relevant parameters of the second type of historical earthquake events involving various general stations within the selected area. The relevant parameters include epicentral distance and maximum ground motion amplitude. The second type of historical earthquake events are historical earthquake events with an epicentral distance greater than or equal to a preset threshold. After substituting the relevant parameters of the second type of historical earthquake events involving each general station into the magnitude estimation model, the least squares method is used for fitting to obtain the general station gauge function with an epicentral distance greater than or equal to the preset threshold.

[0007] Preferably, the expression for the magnitude estimation model is: Mest = log 10 (Um) + R(Δ); In the formula, Mest represents the estimated magnitude of the station; Δ represents the epicentral distance; Um represents the maximum ground motion amplitude; and R(Δ) represents the gauge function.

[0008] Preferably, the magnitude correction value for each station within the selected area is calculated based on the following formula: ; In the formula, This represents the magnitude correction value for the i-th station within the selected area; This represents the number of historical earthquake events that the i-th station participated in; This represents the actual reference magnitude of the j-th historical earthquake event in which the i-th station participated within the selected area; This represents the estimated magnitude of the j-th historical earthquake event involving the i-th station within the selected area.

[0009] Preferably, the estimated magnitude of the first reported earthquake from the first triggering station is calculated based on the gauge function, maximum ground motion amplitude, epicentral distance, and magnitude correction value, including the following steps: Substitute the epicentral distance of the first triggering station into the gauge function of the first triggering station to obtain the gauge function value of the first triggering station. Find the base-10 logarithm of the maximum seismic amplitude at the first triggering station; The sum of the gauge function value of the first triggering station, the logarithm of the maximum ground motion amplitude of the first triggering station to base 10, and the magnitude correction value of the first triggering station is used to obtain the estimated magnitude of the first reported earthquake at the first triggering station.

[0010] Preferably, based on the gauge function of each triggering station, the maximum ground motion amplitude at time t, the epicentral distance at time t, and the magnitude correction value, the estimated magnitude of each triggering station at time t is calculated, specifically including the following steps: Substitute the epicentral distance of the k-th triggering station at time t into the gauge function of the k-th triggering station to obtain the gauge function value of the k-th triggering station at time t; where k = 1, 2, ..., K; K represents the number of stations that have been triggered at time t; Find the base-10 logarithm of the maximum seismic amplitude at time t for the k-th triggering station; The estimated magnitude of the k-th triggering station at time t is obtained by summing the gauge function value of the k-th triggering station at time t, the logarithm of the maximum ground motion amplitude of the k-th triggering station at time t (base 10), and the magnitude correction value of the k-th triggering station.

[0011] Preferably, the merged magnitude at time t is obtained based on the following formula: ; ; In the formula, This represents the merged magnitude at time t; This represents the weight of the k-th trigger station at time t; These are preset coefficients; This represents the estimated magnitude of the earthquake at time t, indicated by the k-th triggering station; This indicates the trigger time of the k-th triggering station.

[0012] Preferably, the final estimated magnitude at time t is obtained based on the following formula: Mf(t) = max(M(t), MI); MI = f(I0); In the formula, Mf(t) represents the final estimated magnitude at time t; MI represents the intensity magnitude; I0 represents the epicentral intensity calculated by PGA or PGV; f represents the function that maps the epicentral intensity to the intensity magnitude; max(M(t), MI) means taking the larger of M(t) and MI.

[0013] Preferably, the final estimated magnitude at time t is obtained based on the following formula: Mf(t) = ω1 M(t) + ω2 MI; MI = f(I0); ω1+ω2=1; In the formula, Mf(t) represents the final estimated magnitude at time t; MI represents the intensity magnitude; I0 represents the epicentral intensity calculated by PGA or PGV; f represents the function that maps the epicentral intensity to the intensity magnitude; ω1 and ω2 represent preset coefficients.

[0014] As can be seen from the above technical solution, compared with the prior art, the present invention discloses a method for rapid estimation of earthquake magnitude for regional earthquake early warning, which can achieve the following beneficial effects: 1) This invention constructs four types of gauge functions, which significantly enhances the near-field earthquake compensation capability for epicentral distances of less than 50 kilometers, overcomes the problem of systematic underestimation under near-field conditions of traditional gauge functions, and effectively improves the reliability of magnitude early warning.

[0015] 2) The magnitude correction values ​​established by this invention for each station significantly reduce the impact of station heterogeneity. The estimation error has been reduced, improving the stability and adaptability of magnitude estimation.

[0016] 3) The magnitude fusion mechanism designed in this invention can be implemented 3 seconds, 5 seconds, 10 seconds, etc. after an earthquake occurs. The phased output of continuous and stable estimation results reduces magnitude jumps and improves the decision-making continuity and timeliness control capability of the earthquake early warning system.

[0017] 4) This invention introduces intensity magnitude to correct the merged magnitude, overcoming the limitations of traditional ML magnitude correction in strong earthquakes. Technical bottlenecks in valuation saturation and false alarm levels under earthquake conditions.

[0018] 5) The method of this invention relies on existing early warning network data, requires no additional hardware equipment, and has high computational efficiency. It is highly efficient and can be seamlessly integrated into earthquake early warning systems, possessing good deployment feasibility and promotion prospects. It is particularly suitable for the Northwest and Plateau regions with dense seismic stations and complex geological structures. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0020] Figure 1 The flowchart illustrates a method for rapid magnitude estimation in regional earthquake early warning, as provided by this invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] like Figure 1 As shown in the figure, this invention discloses a method for rapid estimation of earthquake magnitude for regional earthquake early warning, including the following steps: S1: Obtain the maximum ground motion amplitude, epicentral distance, station type, and magnitude correction value of the first triggering station when an earthquake occurs in the selected area; wherein, the station type includes a reference station and a general station; Understandably, according to the station construction specifications, stations based on bedrock are defined as benchmark stations, while stations deployed on shallow soil or structures are defined as general stations.

[0023] It is understandable that the magnitude correction value is obtained based on the station number of the first triggering station. In one or more embodiments, magnitude correction values ​​for each station within the selected area are calculated based on the estimated magnitudes and actual reference magnitudes of historical earthquake events in which each station participated within the selected area.

[0024] In one or more embodiments, the magnitude correction value for each station within the selected area is calculated based on the following formula: ; In the formula, This represents the magnitude correction value for the i-th station within the selected area; This represents the number of historical earthquake events that the i-th station participated in; This represents the actual reference magnitude of the j-th historical earthquake event in which the i-th station participated within the selected area; This represents the estimated magnitude of the j-th historical earthquake event involving the i-th station within the selected area.

[0025] It is understandable that: calculations are obtained Post-output station calibration value table {ID i Type i , S i , N i}, when Type is known i At that time, the station calibration value table {ID} can be used. i Type i , S i , N i Get Type i The corresponding S iTherefore, the corresponding magnitude correction value can be obtained based on the station number of the first triggering station; where ID i Type i The station number and station type of the i-th station in the selected area are represented sequentially.

[0026] S2: Obtain the gauge function of the first triggering station based on the station type and epicentral distance of the first triggering station; It is understandable that: If the station type of the first triggering station is a reference station and the epicentral distance of the first triggering station is less than a preset threshold (e.g., 50km), then the gauge function of the first triggering station is the gauge function of the reference station with an epicentral distance less than the preset threshold. If the station type of the first triggering station is a reference station and the epicentral distance of the first triggering station is greater than or equal to a preset threshold (e.g., 50km), then the gauge function of the first triggering station is the gauge function of the reference station with an epicentral distance greater than or equal to the preset threshold. If the station type of the first triggering station is a general station and the epicentral distance of the first triggering station is less than a preset threshold (e.g., 50km), then the gauge function of the first triggering station is the gauge function of a general station with an epicentral distance less than the preset threshold. If the first triggering station is a general station and its epicentral distance is greater than or equal to a preset threshold (e.g., 50 km), then the gauge function of the first triggering station is the gauge function of a general station with an epicentral distance greater than or equal to the preset threshold.

[0027] In one or more embodiments, the rapid estimation method further includes the following steps: constructing several gauge functions based on the station type of each station in the selected area and relevant parameters of historical earthquake events in which each station participated; wherein, the relevant parameters include epicentral distance and maximum ground motion amplitude; the several gauge functions include a benchmark station gauge function with an epicentral distance less than a preset threshold, a benchmark station gauge function with an epicentral distance greater than or equal to a preset threshold, a general station gauge function with an epicentral distance less than a preset threshold, and a general station gauge function with an epicentral distance greater than or equal to a preset threshold.

[0028] In one or more embodiments, the plurality of gauge functions are constructed based on the following steps: Obtain relevant parameters of the first type of historical earthquake events involving each reference station in the selected area, wherein the relevant parameters include epicentral distance and maximum ground motion amplitude, and the first type of historical earthquake events are historical earthquake events with an epicentral distance less than a preset threshold; After substituting the relevant parameters of the first type of historical earthquake events in which each base station participated into the magnitude estimation model, the least squares method was used to fit the model to obtain the base station gauge function for the epicentral distance being less than the preset threshold. Obtain relevant parameters of the second type of historical earthquake events involving each reference station in the selected area. The relevant parameters include epicentral distance and maximum ground motion amplitude. The second type of historical earthquake events are historical earthquake events with an epicentral distance greater than or equal to a preset threshold. After substituting the relevant parameters of the second type of historical earthquake events in which each base station participated into the magnitude estimation model, the least squares method was used to fit the model to obtain the base station gauge function with the epicentral distance greater than or equal to the preset threshold. Obtain relevant parameters of the first type of historical earthquake events involving various general stations within the selected area. The relevant parameters include epicentral distance and maximum ground motion amplitude. The first type of historical earthquake events are historical earthquake events with an epicentral distance less than a preset threshold. After substituting the relevant parameters of the first type of historical earthquake events in which each general station participated into the magnitude estimation model, the least squares method was used to fit the model to obtain the general station gauge function where the epicentral distance is less than the preset threshold. Obtain relevant parameters of the second type of historical earthquake events involving various general stations within the selected area. The relevant parameters include epicentral distance and maximum ground motion amplitude. The second type of historical earthquake events are historical earthquake events with an epicentral distance greater than or equal to a preset threshold. After substituting the relevant parameters of the second type of historical earthquake events involving each general station into the magnitude estimation model, the least squares method is used for fitting to obtain the general station gauge function with an epicentral distance greater than or equal to the preset threshold.

[0029] In one or more embodiments, the magnitude estimation model is expressed as follows: Mest = log 10 (Um) + R(Δ); In the formula, Mest represents the estimated magnitude of the station; Δ represents the epicentral distance; Um represents the maximum ground motion amplitude; and R(Δ) represents the gauge function.

[0030] It should be noted that when performing least squares fitting, each residual ε is guaranteed to equal Mref. The mean of Mest is close to 0, and the standard deviation is no more than ±0.3; where Mref represents the actual reference magnitude of the station.

[0031] S3: Calculate the estimated magnitude of the first earthquake reported by the first triggering station based on the gauge function, maximum ground motion amplitude, epicentral distance, and magnitude correction value. In one or more embodiments, the estimated magnitude of the first reported earthquake from the first triggering station is calculated based on the gauge function, maximum ground motion amplitude, epicentral distance, and magnitude correction value of the first triggering station, including the following steps: Substitute the epicentral distance of the first triggering station into the gauge function of the first triggering station to obtain the gauge function value of the first triggering station. Find the base-10 logarithm of the maximum seismic amplitude at the first triggering station; The sum of the gauge function value of the first triggering station, the logarithm of the maximum ground motion amplitude of the first triggering station to base 10, and the magnitude correction value of the first triggering station is used to obtain the estimated magnitude of the first reported earthquake at the first triggering station.

[0032] The specific expression is: M(1) = log 10 (U m,1 ) + R d (Δ1) + S1; In the formula, M(1) represents the estimated magnitude reported by the first triggering station; Δ1 represents the epicentral distance of the first triggering station; R d This represents the gauge function of the first triggering station (the gauge function of the first triggering station is one of the following: a reference station gauge function with an epicentral distance less than a preset threshold, a reference station gauge function with an epicentral distance greater than or equal to a preset threshold, a general station gauge function with an epicentral distance less than a preset threshold, or a general station gauge function with an epicentral distance greater than or equal to a preset threshold); R d (Δ1) represents the gauge function value of the first triggering station; U m,1 This represents the maximum seismic amplitude of the first triggering station; log 10 (U m,1 S1 represents the base-10 logarithm of the maximum ground motion amplitude of the first triggering station; S1 represents the magnitude correction value of the first triggering station.

[0033] S4: Obtain the maximum ground motion amplitude, epicentral distance, station type, and magnitude correction value for each triggering station at time t; where time t is a time after the earthquake occurs; It is understandable that, similar to the first triggering station, the corresponding magnitude correction value can be obtained based on the station number of each triggering station.

[0034] S5: Obtain the gauge function for each triggering station based on its station type and epicentral distance at time t. It is understandable that: If the triggering station is a reference station and the epicentral distance of the triggering station at time t is less than a preset threshold (e.g., 50 km), then the gauge function of the triggering station is the gauge function of the reference station with an epicentral distance less than the preset threshold. If the triggering station is a reference station and the epicentral distance of the triggering station at time t is greater than or equal to a preset threshold (e.g., 50 km), then the gauge function of the triggering station is the gauge function of the reference station with an epicentral distance greater than or equal to the preset threshold. If the triggering station is a general station and the epicentral distance of the triggering station at time t is less than a preset threshold (e.g., 50 km), then the gauge function of the triggering station is the gauge function of a general station with an epicentral distance less than the preset threshold. If the triggering station is a general station and the epicentral distance of the triggering station at time t is greater than or equal to a preset threshold (e.g., 50 km), then the gauge function of the triggering station is the gauge function of a general station with an epicentral distance greater than or equal to the preset threshold.

[0035] S6: Based on the gauge function of each triggering station, the maximum ground motion amplitude at time t, the epicentral distance at time t, and the magnitude correction value, calculate the estimated magnitude of each triggering station at time t; In one or more embodiments, the estimated magnitude of each triggering station at time t is calculated based on the gauge function of each triggering station, the maximum ground motion amplitude at time t, the epicentral distance at time t, and the magnitude correction value. This specifically includes the following steps: Substitute the epicentral distance of the k-th triggering station at time t into the gauge function of the k-th triggering station to obtain the gauge function value of the k-th triggering station at time t; where k = 1, 2, ..., K; K represents the number of stations that have been triggered at time t; Find the base-10 logarithm of the maximum seismic amplitude at time t for the k-th triggering station; The estimated magnitude of the k-th triggering station at time t is obtained by summing the gauge function value of the k-th triggering station at time t, the logarithm of the maximum ground motion amplitude of the k-th triggering station at time t (base 10), and the magnitude correction value of the k-th triggering station.

[0036] The specific expression is: M k (t) = log 10 (U m,t,k ) + R d，k (Δ t,k ) + S k ; In the formula, M k (t) represents the estimated magnitude at time t by the k-th triggering station; Δ t,k R represents the epicentral distance of the k-th triggering station at time t; d，k Represents the gauge function of the k-th triggering station (the gauge function of the k-th triggering station is one of the following: a reference station gauge function with an epicentral distance less than a preset threshold, a reference station gauge function with an epicentral distance greater than or equal to a preset threshold, a general station gauge function with an epicentral distance less than a preset threshold, or a general station gauge function with an epicentral distance greater than or equal to a preset threshold); R d，k (Δ t,k ) represents the gauge function value of the k-th trigger station at time t; U m,t,kRepresents the maximum seismic amplitude at time t for the k-th triggering station; log 10 (U m,t,k S represents the base-10 logarithm of the maximum seismic amplitude at time t for the k-th triggering station; k This represents the magnitude correction value for the k-th triggering station.

[0037] S7: The estimated magnitudes of each triggering station at time t are fused using the weights of each triggering station at time t to obtain the fused magnitude at time t; In one or more embodiments, the combined magnitude at time t is obtained based on the following formula: ; ; In the formula, This represents the merged magnitude at time t; This represents the weight of the k-th trigger station at time t; These are preset coefficients; This represents the estimated magnitude of the earthquake at time t, indicated by the k-th triggering station; This indicates the trigger time of the k-th triggering station.

[0038] S8: If the merged magnitude at time t is greater than a preset threshold, the merged magnitude at time t is corrected using the intensity magnitude to obtain the final estimated magnitude at time t.

[0039] In one or more embodiments, if the merged magnitude at time t is greater than 6.5, it will tend to saturate. In this case, the intensity magnitude is used to correct the merged magnitude at time t to obtain the final estimated magnitude at time t.

[0040] In one or more embodiments, the final estimated magnitude at time t is obtained based on the following formula: Mf(t) = max(M(t), MI); MI = f(I0); In the formula, Mf(t) represents the final estimated magnitude at time t; MI represents the intensity magnitude; I0 represents the epicentral intensity calculated by PGA or PGV; f represents the function that maps the epicentral intensity to the intensity magnitude; max(M(t), MI) means taking the larger of M(t) and MI.

[0041] In one or more embodiments, the final estimated magnitude at time t is obtained based on the following formula: Mf(t) = ω1 M(t) + ω2 MI; MI = f(I0); ω1+ω2=1; In the formula, Mf(t) represents the final estimated magnitude at time t; MI represents the intensity magnitude; I0 represents the epicentral intensity calculated by PGA or PGV; f represents the function that maps the epicentral intensity to the intensity magnitude; ω1 and ω2 represent preset coefficients.

[0042] In one or more embodiments, based on Output the pre-corrected magnitude evolution curve, and output the corrected magnitude evolution curve based on Mf(t). In one or more embodiments: After obtaining the first estimated magnitude M(1) from the first triggering station, M(1), timestamp, confidence level, etc. are sent to the earthquake early warning system in XML or JSON format; If the merged magnitude at time t is greater than the preset threshold, then Mf(t), timestamp, confidence level, station number and station type of K triggering stations will be sent to the earthquake early warning system in XML or JSON format. If the merged magnitude at time t is less than the preset threshold, then M(t), timestamp, confidence level, station number and station type of K triggering stations will be sent to the earthquake early warning system in XML or JSON format. Earthquake early warning systems are used for initial reporting level classification, early warning range mapping, intensity rapid reporting triggering, and disaster prediction.

[0043] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0044] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A regional earthquake early warning magnitude rapid estimation method, characterized in that, The method comprises the following steps: obtaining the maximum ground motion amplitude, epicentral distance, station type and magnitude correction value of the first triggered station when the earthquake occurs in the selected area; wherein the station type includes reference stations and general stations; obtaining the gauge function of the first triggered station based on the station type and epicentral distance of the first triggered station; calculating the first report estimated magnitude of the first triggered station based on the gauge function, maximum ground motion amplitude, epicentral distance and magnitude correction value of the first triggered station; obtaining the maximum ground motion amplitude, epicentral distance, station type and magnitude correction value of each triggered station at time t; wherein t is a time after the earthquake occurs; obtaining the gauge function of each triggered station based on the station type and epicentral distance at time t; calculating the estimated magnitude of each triggered station at time t based on the gauge function, maximum ground motion amplitude at time t, epicentral distance at time t and magnitude correction value of each triggered station; fusing the estimated magnitude of each triggered station at time t using the weight of each triggered station at time t to obtain the fused magnitude at time t; if the fused magnitude at time t is greater than a preset threshold, correcting the fused magnitude at time t using the intensity magnitude to obtain the final estimated magnitude at time t.

2. The method of claim 1, wherein, The method further comprises the following steps: constructing a plurality of gauge functions based on the station type of each station in the selected area and the related parameters of historical earthquake events participated by each station; wherein the related parameters include epicentral distance and maximum ground motion amplitude; the plurality of gauge functions include reference station gauge functions with epicentral distance less than a preset threshold, reference station gauge functions with epicentral distance greater than or equal to a preset threshold, general station gauge functions with epicentral distance less than a preset threshold, and general station gauge functions with epicentral distance greater than or equal to a preset threshold; calculating the magnitude correction value of each station in the selected area based on the estimated magnitude and actual reference magnitude of historical earthquake events participated by each station in the selected area.

3. The method of claim 2, wherein the method comprises: The plurality of gauge functions are constructed based on the following steps: obtaining the related parameters of the first type of historical earthquake events participated by each reference station in the selected area, wherein the related parameters include epicentral distance and maximum ground motion amplitude, and the first type of historical earthquake events are historical earthquake events with epicentral distance less than a preset threshold; obtaining the reference station gauge function with epicentral distance less than a preset threshold by substituting the related parameters of the first type of historical earthquake events participated by each reference station into a magnitude estimation model and fitting using the least squares method; obtaining the related parameters of the second type of historical earthquake events participated by each reference station in the selected area, wherein the related parameters include epicentral distance and maximum ground motion amplitude, and the second type of historical earthquake events are historical earthquake events with epicentral distance greater than or equal to a preset threshold; obtaining the reference station gauge function with epicentral distance greater than or equal to a preset threshold by substituting the related parameters of the second type of historical earthquake events participated by each reference station into a magnitude estimation model and fitting using the least squares method; obtaining the related parameters of the first type of historical earthquake events participated by each general station in the selected area, wherein the related parameters include epicentral distance and maximum ground motion amplitude, and the first type of historical earthquake events are historical earthquake events with epicentral distance less than a preset threshold; The relevant parameters of the first type of historical earthquake events participated by each general station are substituted into a magnitude estimation model, and fitting is performed by using a least square method to obtain a general station gauge function with a epicentral distance less than a preset threshold value; Relevant parameters of the second type of historical earthquake events participated by each general station in a selected region are acquired, wherein the relevant parameters include an epicentral distance and a maximum ground motion amplitude, and the second type of historical earthquake events are historical earthquake events with an epicentral distance greater than or equal to a preset threshold value; The relevant parameters of the second type of historical earthquake events participated by each general station are substituted into a magnitude estimation model, and fitting is performed by using a least square method to obtain a general station gauge function with an epicentral distance greater than or equal to a preset threshold value.

4. The method of claim 3, wherein the method comprises: The expression of the magnitude estimation model is as follows: Mest = log 10 (Um) + R(Δ); In the formula, Mest represents an estimated magnitude of a station; Δ represents an epicentral distance; Um represents a maximum ground motion amplitude, and R(Δ) represents a gauge function.

5. The method of claim 2, wherein the method comprises: A magnitude correction value of each station in the selected region is calculated based on the following formula: ； wherein Mci represents the magnitude correction value for the ith station in the selected region; Nci represents the number of historical seismic events in which the ith station participated; Mci,j represents the actual reference magnitude of the jth historical seismic event in which the ith station participated in the selected region; Mci,j represents the estimated magnitude of the jth historical seismic event in which the ith station participated in the selected region.

6. The method of claim 1, wherein, Based on the gauge function of the first triggered station, the maximum ground motion amplitude, the epicentral distance and the magnitude correction value, a first reported estimated magnitude of the first triggered station is calculated, including the following steps: The epicentral distance of the first triggered station is substituted into the gauge function of the first triggered station to obtain a gauge function value of the first triggered station; The logarithm to the base 10 of the maximum ground motion amplitude of the first triggered station is obtained; The sum of the gauge function value of the first triggered station, the logarithm to the base 10 of the maximum ground motion amplitude of the first triggered station and the magnitude correction value of the first triggered station is obtained to obtain the first reported estimated magnitude of the first triggered station.

7. The method of claim 1, wherein the method further comprises: Based on the gauge function of each triggered station, the maximum ground motion amplitude at t, the epicentral distance at t and the magnitude correction value, an estimated magnitude of each triggered station at t is calculated, specifically including the following steps: The epicentral distance of the kth triggered station at t is substituted into the gauge function of the kth triggered station to obtain a gauge function value of the kth triggered station at t; wherein k = 1, 2, …, K; K represents the number of stations triggered at t; The logarithm to the base 10 of the maximum ground motion amplitude of the kth triggered station at t is obtained; The sum of the gauge function value of the kth triggered station at t, the logarithm to the base 10 of the maximum ground motion amplitude of the kth triggered station at t and the magnitude correction value of the kth triggered station is obtained to obtain the estimated magnitude of the kth triggered station at t.

8. The method of claim 7, wherein the method further comprises: The fusion magnitude at t is obtained based on the following formula: ； ； In the formula, represents the fusion magnitude at the t moment; represents the weight of the kth trigger station at the t moment; is a preset coefficient; represents the estimated magnitude of the kth trigger station at the t moment; represents the trigger time of the kth trigger station.

9. The method of claim 8, wherein the method further comprises: The final estimated magnitude at t is obtained based on the following formula: Mf(t) = max(M(t), MI); MI = f(I0); In the formula, Mf(t) represents the final estimated magnitude at t; MI represents the intensity magnitude; I0 represents the epicentral intensity calculated from PGA or PGV; f represents a function of mapping the epicentral intensity to the intensity magnitude; max(M(t), MI) represents the larger one of M(t) and MI.

10. The method of claim 8, wherein the method further comprises: The final estimated magnitude at t is obtained based on the following formula: Mf(t) = ω1 M(t) + ω2 MI; MI = f(I0); ω1+ω2=1; In the formula, Mf(t) represents the final estimated magnitude at the t moment; MI represents the intensity magnitude; I0 represents the epicenter intensity calculated by PGA or PGV; f represents a function of mapping the epicenter intensity to the intensity magnitude; and ω1 and ω2 represent preset coefficients.

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