华北地区形变异常方向与5级地震震中及区域应力场的关系  

The Relationship Between the Direction of Deformation Anomaly and the Epicenter and Regional Stress Field of the M5.0 Earthquake in North China

作　　者：李梦莹[1] 张志宏[1] 贾丽华[1] LI Mengying;ZHANG Zhihong;JIA Lihua(Liaoning Earthquake Agency,Liaoning Shenyang 110034,China)

机构地区：[1]辽宁省地震局,辽宁沈阳110034

出　　处：《防灾减灾学报》2024年第4期36-41,共6页Journal of Disaster Prevention And Reduction

基　　金：中国地震局2024年度震情跟踪定向工作任务(2024010411)。

摘　　要：基于1970年以来华北地区发生的5级地震,对地震前的倾斜异常方向与震中位置、发震构造进行了统计分析,在筛选出的60次倾斜异常中,57%的异常方向直接指向震中;37%的异常则背向震中;而约6%的异常情况在震前出现了由背向震中转向指向震中的现象。结果表明:震前倾斜异常出现转向现象的地震,主要出现在地方震或震中距离异常点200 km以内的近震。未来5级地震的震中多集中在倾斜异常点以南区域。然而,当震中距离异常点超过300 km时,倾斜异常方向对未来震中指示意义不是十分明确。Among the M5.0 earthquakes that occurred in North China since 1970,a statistical study was conducted on the orientation of the inclination anomaly and the location of the earthquake focus,as well as the seismogenic structure.Among the 60-item tilt anomalies,57%pointed epicenter,37%were opposite to the epicenter,and about 6%of the cases,a turning phenomenon was observed,that is,firstly face away from the epicenter and then point to the epicenter.The results indicate that earthquakes with abnormal tilt and turning phenomena mainly occur in local earthquakes or near earthquakes within 200km of the epicenter from the abnormal point.In addition,the epicenter of future earthquakes with a magnitude of 5 is mostly concentrated in the south of the inclined anomaly point.However,when the epicenter is more than 300 kilometers away from the anomaly point,the direction of the tilt anomaly is not very clear in indicating the future epicenter.

关 键 词：地倾斜 震中 发震构造 断裂 形变异常 

分 类 号：P315.7[天文地球—地震学]