考虑椭圆模型M_W≥5.5地震震源参数时域计算方法  

Time-domain method of source parameters considering elliptic model for MW≥5.5 earthquakes

作　　者：王江[1,2] 马强 陶冬旺[1,2] 章旭斌 解全才 林德昕[1,2] WANG Jiang;MA Qiang;TAO DongWang;ZHANG XuBin;XIE QuanCai;LIN DeXin(Key Laboratory of Earthquake Engineering and Engineering Vibration,Institute of Engineering Mechanics,China Earthquake Administration,Harbin 150080,China;Key Laboratory of Earthquake Disaster Mitigation,Ministry of Emergency Management,Harbin 150080,China)

机构地区：[1]中国地震局工程力学研究所地震工程与工程振动重点实验室,哈尔滨150080 [2]地震灾害防治应急管理部重点实验室,哈尔滨150080

出　　处：《地球物理学报》2024年第3期1093-1107,共15页Chinese Journal of Geophysics

基　　金：中国地震局工程力学研究所基本科研业务费专项(2021B08);黑龙江省自然科学基金项目(LH2022E119)联合资助。

摘　　要：为提高时效性,地震预警系统对震源的处理一般采用“点源”假定,不考虑震源尺度、破裂方向和震源区应力降,对震源参数简化处理使得预测地震动参数分布过于粗略,特别是对破坏性大震.本文应用日本地震(M_W≥5.5)强震动数据,考虑椭圆震源模型,提出了一种适用于中、大地震矩震级、拐角频率和应力降等震源参数时域计算方法,并分析了场地效应、地震动传播衰减、震源效应和滤波频带等因素对时域方法的影响.结果表明,该方法能利用P波信息快速获取震源能量释放过程,量化随破裂传播震源谱拐角频率、应力降和破裂面积的演化过程,为地震动预测提供更多重要的震源参数.In order to enhance the timeliness, earthquake early warning systems commonly assume a point source without considering the size of source, rupture direction and stress drop in the source area. The simplified processing of source parameters leads to a coarse prediction of the ground motion distribution, especially for destructive large earthquakes. In this paper, we utilize strong motion recordings from Japanese earthquakes (MW≥5.5), incorporate an elliptical source model, and propose a time-domain approach for determining source parameters such as moment magnitude, corner frequency and stress drop of moderate and large earthquakes. We also analysis the impact of site effect, ground motion propagation attenuation, source effects and filtering frequency bands on the time domain method. The results show that this method can use P-wave information to rapidly obtain the source energy release process, quantify the evolution process of the corner frequencies in the source spectrum, stress drop and rupture area with rupture propagation, providing crucial source parameters for predicting ground motion.

关 键 词：地震预警 时间域 矩震级 拐角频率 应力降 破裂面积 

分 类 号：P315[天文地球—地震学]