摘要
采用地表地质调查、地貌调查、建筑物震害调查方法,结合震源机制解及余震分布、地震烈度图,初步探讨了广西北流MS 5.2地震发震构造特征。研究结果表明:广西北流MS 5.2地震发生在NW走向的石窝断裂和NE走向的新丰断裂交汇部位,发震构造为石窝断裂;石窝断裂露头平均产状222°∠81°,最新活动性质为具有正断分量的左行走滑断层,最新活动时代为早第四纪;新丰断裂最新运动性质为逆断,最新活动时代为早第四纪;在现今NW向主压应力作用下,石窝断裂发生破裂,发生MS 5.2地震,同震运动方式以右行走滑为主,余震震中呈NW向分布。极震区建筑物震害调查得出的运动方向与震源机制解显示的同震运动方向一致。
By using the methods of surface structure survey,geomorphology survey and building damage surveyicombined with focal mechanism solution,aftershock distribution and seismic intensity map,the seismogenic structure of the Beiliu MS5.2 earthquake in Guangxi is discussed.A preliminary research show that theBeiliu MS5.2 earthquake occurred at the intersection of the NW trending Shiwo fault and the NE trending Xinfeng fault.The average occurrence of Shiwo fault is 222°∠81°.The latest movement direction is left-lateral with normal faulting component,and its newest age of activity is early Quaternary.The latest movement direction of Xinfeng fault is reverse,and its newest age of activity is early Quaternary.Under the NW-trending regional compressive stress,the NW-trending Shiwo fault ruptured with a MS5.2 earthquake occurring,the coseismic movement mode was mainly right strike slip,and the aftershocks distributed along the Shiwo fault in NW direction.The coseismic ground motion direction reflected by the building damage in the meizoseismal area is consistent with which shown by the focal mechanism solution.
作者
李冰溯
李细光
聂冠军
赵修敏
韦王秋
钟德伟
杨钦杰
LI Bingsu;LI Xiguang;NIE Guanjun;ZHAO Xiumin;WEI Wangqiu;ZHONG Dewei;YANG Qinjie(Earthquake Agency of Guangxi Zhuang Autonomous Region,Nanning 530022,China)
出处
《华北地震科学》
2019年第S01期17-23,共7页
North China Earthquake Sciences
基金
广西科学研究与技术开发计划项目(AB17195022,AB18126040)
广西科技攻关计划项目(1377002,12426001-1)
广西重点研发计划项目(AB1850042)
关键词
广西北流MS5.2地震
石窝断裂
新丰断裂
发震构造
同震运动
Beiliu MS5.2 earthquake in Guangxi
Shiwo fault
Xinfeng fault
seismogenic structure
coseismic ground motion
