海域俯冲带高频地震动模拟——以2021年2月13日日本福岛M_(S)7.1地震为例  

Simulation of High-frequency Ground Motions in the Subduction Zone of the Sea Area——Taking the Fukushima M_(S)7.1 Earthquake on February 13, 2021 as an Example

作　　者：李宗超[1] 高孟潭[1] 孙吉泽 司洁戈 吴清[1] 李奇 Li Zongchao;Gao Mengtan;Sun Jize;Si Jiege;Wu Qing;Li Qi(Institute of Geophysics,China Earthquake Administration,Beying 100081,China;Shenzhen Academy of Disaster Prevention and Reduction,Shenzhen 518003,China;The 3rd Research Institute ofCETC,Beying 100015,China)

机构地区：[1]中国地震局地球物理研究所,北京100081 [2]深圳防灾减灾技术研究院,深圳518003 [3]中国电子科技集团公司第三研究所,北京100015

出　　处：《震灾防御技术》2022年第3期516-528,共13页Technology for Earthquake Disaster Prevention

基　　金：国家重点研发计划(2019YFC1511004-02);科技部基础资源调查专项(2018FY100504);中国地震局地球物理研究所基本科研业务费专项(DQJB22B21,DQJB22R30)。

摘　　要：2021年2月13日,日本福岛近海发生M7.1地震,震中距海岸线约70km,震源深度接近60km,造成了较大范围的震害影响。考虑地震应急及地震动强度特征预测的应用前景等,利用经验格林函数法快速估计了本次地震的高频地震动(1.0~20.0Hz)空间分布特征及加速度时程,并结合实际地形、场地覆盖层等信息对部分台站地震动模拟结果进行修正,最终获得较可靠的地震动预测结果。研究结果表明,在具备合适小震记录时(余震及前震),可较准确地再现大震的高频地震动主要特征,模拟结果与真实记录拟合较好;地震动模拟过程中需考虑盆地等特殊地形及覆盖土层对地震动的放大作用影响,这也是未来利用经验格林函数法合成大震时需重点考虑的因素。On February 13, 2021, an M7.1 earthquake occurred in the coast of Fukushima, Japan. The epicenter was about 70 km away from the coastline and the focal depth was nearly 60 km, resulting in a wide range of earthquake damage. From the perspective of earthquake emergency and the application prospect of ground motion evaluation, this paper attempts to quickly evaluate the spatial distribution characteristics and acceleration time history of high-frequency ground motion of this earthquake based on the empirical Green’s function method, and modifies the ground motion simulation results of some stations in combination with the actual terrain,deep-thickness overburden layer and other information. Finally, more reliable ground motion evaluation results are obtained. The results show that the main characteristics of high-frequency ground motion of large earthquakes can be accurately reproduced when appropriate small earthquake records(aftershocks and foreshocks) are available, and the simulation results are also well fitted with the real records;In the process of ground motion simulation, the influence of basin and other special terrain and thick overburden on the amplification of ground motion need to be considered, which is also the key factor to be considered when synthesizing large earthquakes by empirical Green’s function method in the future.

关 键 词：高频地震动评估 小震记录 经验格林函数法 地震动修正系数 应用可行性 

分 类 号：P738.4[天文地球—海洋地质]