2021年6月17日承德M_(L)3.6地震重新定位及震源机制解研究  

Analysis on relocation and focal mechanism of the Chengde M_(L)3.6 earthquake on June 17,2021

作　　者：王嘉琦 张玉林 杨东辉 袁国旭 Wang Jiaqi;Zhang Yulin;Yang Donghui;Yuan Guoxu(Chengde Earthquake Monitoring Center Station of Hebei Earthquake Agency,Hebei Chengde 067000,China)

机构地区：[1]承德地震监测中心站,河北承德067000

出　　处：《地震科学进展》2024年第6期373-382,共10页Progress in Earthquake Sciences

基　　金：河北省地震局科技星火计划(DZ2023120800009)资助。

摘　　要：2021年6月17日河北省承德市双桥区发生M_(L)3.6地震。基于河北区域数字地震台网资料,采用双差定位算法重新定位该地震序列,获得了精确震中分布。利用小震拟合法计算得到该次地震对应断层面参数为:走向63.76°,倾角70.52°。采用CAP方法反演获得了主震的最佳单位震源参数、矩张量解和双力偶解。其中,最佳断层面解为:走向63.4°,倾角52.8°。根据断层中心解计算,确定最终发震断层面参数为走向63.59°,倾角61.66°,与该区域的双塔山—双峰寺断裂吻合。考虑区域构造特征,推测本次地震可能由主张应力在该断裂上挤压而诱发,属于一个典型的正断层活动。本次研究为确定承德地震的发震构造及该地区的应力场状态提供了重要依据。On June 17,2021,an M_(L)3.6 earthquake occurred in Shuangqiao District,Chengde City,Hebei Province.Based on the data of Hebei regional digital seismic network,the double-difference location algorithm was used to reposition the earthquake sequence and a precise epicenter distribution was obtained.The fault plane parameters of this earthquake were computed using the small event fitting method as follows,strike 63.76°and dip 70.52°.The main shock’s optimal unit source time function,moment tensor solution,and double couple solution are obtained by CAP method.Among them,the best fault plane solution is strike 63.4°and dip 52.8°.Based on the fault center solution calculations,the final fault plane parameters were determined to be strike 63.59°and dip 61.66°,which aligns with the region’s Shuangtashan-Shuangfengsi fault.Considering regional tectonic characteristics,it is postulated that this earthquake may have been induced by the principal stress squeezing on the fault,representing a typical normal fault activity.This study provides crucial evidence for identifying the seismogenic structure of the Chengde earthquake and the stress field status in the area.

关 键 词：承德M_(L)3.6地震 震源机制 双差定位 发震构造 

分 类 号：P315.33[天文地球—地震学]