震后近断层震动图的快速产出研究——以2022年1月8日青海门源地震为例  

Study on rapid generation of near-fault Shakemaps after an earthquake:a case of Menyuan earthquake on January 8,2022,Qinhai Province

作　　者：王海云[1,2] 李强 WANG Haiyun;LI Qiang(Institute of Engineering Mechanics,China Earthquake Administration;Key Laboratory of Earthquake Engineering and Engineering Vibration of China Earthquake Administration,Harbin 150080,China)

机构地区：[1]中国地震局工程力学研究所 [2]中国地震局地震工程与工程振动重点实验室,黑龙江哈尔滨150080

出　　处：《世界地震工程》2022年第2期1-9,共9页World Earthquake Engineering

基　　金：中国地震局工程力学研究所基本科研业务费专项资助项目(2018B05);国家自然科学基金联合基金项目(U2139207)。

摘　　要：震后近断层震动图的快速产出对于政府相关部门快速确定地震影响区、评估震害及其导致的经济损失和人员伤亡、科学决策应急救援方案和措施以减轻人员伤亡和财产损失具有重要意义。以2022年门源地震为例,利用滑动分布、应力降均不同的两个震源模型(即,王卫民等反演的震源模型和本研究生成的随机滑动震源模型)以及相同的路径、场地模型和其它输入参数,使用动力学拐角频率的随机有限断层方法和本研究建立的峰值地面速度(PGV)、水平向最大谱烈度(SI)和中国仪器地震烈度(II)的经验模型研究了快速产出近断层震动图(包括峰值地面加速度图、PGV图、SI图、II图和中国地震烈度图)的实效性。结果表明:(1)上述方法和经验模型可用于震后震动图的快速产出,其实效性主要取决于震源、路径和场地模型的可靠性;(2)基于上述两种震源模型产出的地震烈度图与中国地震局发布的该次地震的烈度图在总体上具有高度一致性,均可用于确定地震影响区,但基于反演震源模型产出的地震烈度图可以给出极震区,而基于随机滑动震源模型产出的地震烈度图则需要根据其最大等震线和发震断层的位置大致估计极震区的位置。Rapid generation of near-fault Shakemaps after an earthquake has important significance for government departments to quickly identify earthquake affected area,assess earthquake damage and its resulting economic loss and casualties,and scientifically makes emergency rescue plans and measures to reduce casualties and property losses.Taking 2022 Menyuan earthquake as an example,employing two source models with different slip distribution and stress drops(i.e.,source model inverted by Wang et al.(2022)and random slip source model generated by this study)and the same path,crust and site amplification models and other input parameters,the effectiveness of rapidly generated near-fault Shakemaps(including isoline maps of peak ground acceleration,peak ground velocity(PGV),maximum horizontal spectral intensity(SI),Chinese instrumental seismic intensity(II)and Chinese isoseismal map)after an earthquake is studied by using both stochastic finite-fault method with the dynamic corner frequency and empirical models of PGV,SI,and IIestablished by this study.The results are as follows.(1)The above method and empirical models can be used to rapidly generate the shakemaps after an earthquake,and their effectiveness depends mainly on the reliability of source,path and site models.(2)The isoseismal maps of the earthquake generated by this study using the above two source models are highly consistent with that of the earthquake released by China Earthquake Administration on the whole and can be used to identify earthquake affected area.However,the isoseismal maps generated by the inverted source model can give the meizoseismal area with the strongest shaking and the maximum instrumental seismic intensity in the earthquake,while the isoseismal maps generated by random slip source model can roughly estimate the meizoseismal area according to its maximum isoseismal line and the seismogenic faultlocation.

关 键 词：2022年门源地震 随机有限断层方法 动力学拐角频率 震动图 仪器地震烈度 

分 类 号：P315[天文地球—地震学]