2021年云南漾濞M_(S)6.4地震序列特征及强余震判定  

Characteristics of the 2021 Yangbi, Yunnan M_(S)6.4 Earthquake Sequence and Prediction of Its Strong Aftershocks

作　　者：赵小艳[1] 王光明 张潜[1] 贺素歌[1] 樊文杰[1] 刘自凤 ZHAO Xiaoyan;WANG Guangming;ZHANG Qian;HE Suge;FAN Wenjie;LIU Zifeng(Yunnan Earthquake Agency,Kunming 650224,Yunnan,China)

机构地区：[1]云南省地震局,云南昆明650224

出　　处：《地震研究》2021年第3期309-319,共11页Journal of Seismological Research

基　　金：2019-2023年预防和处置地震灾害能力建设重点任务和中国地震局震情跟踪项目联合资助。

摘　　要：利用云南地震台网观测资料,对2021年漾濞M_(S)6.4地震序列的时空演化特征进行分析,结果表明:漾濞地震序列的空间展布可分为4段,且余震活动衰减非常迅速。通过分析历史地震序列类型、h值、等待时间法、累计频次曲线、初动方向等,判断漾濞M_(S)6.4地震序列为前震-主震-余震型。利用云南地区6级地震最大余震发震时间统计和震级差分布特征分析,认为漾濞M_(S)6.4地震最大余震已经发生。最后讨论了漾濞地震序列4级余震偏多的现象及可能的原因。On the basis of the data of the 2021 Yangbi M_(S)6.4 earthquake sequence recorded by the Yunnan Earthquake Observation Network,we analyze the temporal and spatial evolution characteristics of the sequence.The spatial distribution of the sequence can be divided into 4 sections and the aftershock-activity attenuate rapidly.Through the analysis of the type of the historical earthquake sequences in this area,the method of h-value,the method of dt-t,the method of the cumulative frequency,and first-motion signs of the earthquake wave,we determine that the Yangbi M_(S)6.4 earthquake sequence belongs to foreshock-mainshock-aftershock type.According to the statistics of the original time of the historical strongest aftershocks in Yunnan,and the distribution characteristics of the magnitude differences,we conclude that the strongest aftershock of the Yangbi M_(S)6.4 earthquake has occurred.Finally we discuss the high frequency of ML≥4.0 aftershocks in the sequence and the possible reasons.

关 键 词：漾濞M_(S)6.4地震 地震序列 强余震 

分 类 号：P315.72[天文地球—地震学]