2022年6月10日四川马尔康震群的强震动特征初步分析  

Preliminary analysis of strong motion characteristics of the Maerkang earthquake swarm in Sichuan on June 10,2022

作　　者：徐桐 周宝峰[1,2] 王晓敏 任叶飞 张亚军[3] Xu Tong;Zhou Baofeng;Wang Xiaomin;Ren Yefei;Zhang Yajun(Institute of Engineering Mechanics,China Earthquake Administration,Harbin 150080,China;Key Laboratory of Earthquake Engineering and Engineering Vibration,Harbin 150080,China;Ningxia Communications Construction Co.,Ltd,Yinchuan 750021,China)

机构地区：[1]中国地震局工程力学研究所,哈尔滨150080 [2]地震工程与工程振动重点实验室,哈尔滨150080 [3]宁夏交通建设股份有限公司,银川750021

出　　处：《地震学报》2025年第1期122-135,共14页Acta Seismologica Sinica

基　　金：中国地震局工程力学研究所所长基金(2022C05);黑龙江省自然科学联合引导基金(LH2022E120);宁夏回族自治区重点研发项目(2022BEG03062)共同资助。

摘　　要：2022年6月10日,四川省马尔康市先后发生M_(S)5.8,M_(S)4.1,M_(S)4.4,M_(S)6.0和M_(S)5.2等5次M_(S)>4.0地震,系震群型地震。本研究对此次震群的强震动记录进行滤波降噪处理,对加速度记录进行时频分析,并对比了五次地震间的能量分布情况。通过与第五代区划图对比,分析了不同震级地震的峰值加速度(PGA)、峰值速度(PGV)和加速度反应谱(SA)的衰减关系。同时,计算并对比了五次地震的加速度反应谱和速度反应谱,以及傅里叶幅值谱。结果表明:加速度时程的时频分析和傅里叶谱反映了五次地震具有相似的能量分布形式;第五代区划图中我国青藏地区长轴的衰减模型可以较好地预测3次M_(S)>5.0地震中PGA,PGV和SA(0.2)的衰减,但一定程度上高估了SA(0.5)和SA(1.0);同一强震动台站的加速度反应谱形状、峰值周期相同,且反应T<0.2 s时高度重合;五次地震的水平向傅里叶谱形状相似,且主梄要频率均出现在10—20 Hz频段内;5五次地震同一台站相同方向的加速度反应谱之间、傅里叶谱之间具有很强的相关性。On June 10,2022,an earthquake swarm consisting of M_(S)5.8,M_(S)4.1,M_(S)4.4,M_(S)6.0,and M_(S)5.2 earthquakes occurred in Maerkang,Sichuan,China.This study filtered and analyzed the strong-motion records,conducted time-frequency analysis on acceleration data,and compared energy distributions among these earthquakes.By referencing the Fifth Generation Seismic Zoning Map,the attenuation relationships of peak ground acceleration(PGA),peak ground velocity(PGV),and spectral acceleration(SA)were analyzed.The acceleration and velocity response spectra,as well as Fourier amplitude spectra,were calculated and compared.Results indicate similar energy distribution patterns,with the attenuation model in the Fifth Generation Seismic Zoning Map predicting PGA,PGV,and SA(0.2)well of M_(S)>5.0 earthquakes but overestimating SA(0.5)and SA(1.0).Response spectrum shapes and peak periods were identical at the same station,with values not exceeding local seismic design specifications.Normalized response spectra highly coincided for T<0.2 s in M_(S)>5.0 earthquakes.Horizontal Fourier spectra were similar,with main frequencies in the 10−20 Hz range.Strong correlations were observed among acceleration and Fourier spectra in the same direction at the same station for all five earthquakes.

关 键 词：马尔康地震 震群型地震 衰减关系 反应谱 

分 类 号：P315.31[天文地球—地震学]