2021年5月22日玛多M;7.4地震震前岩石圈磁场变化特征分析  

Characteristic analysis of the lithospheric magnetic anomaly before the Madoi M;7.4 earthquake on 22th May 2021

作　　者：董超 陈斌[1] 袁洁浩[1] 王振东[1] 王粲[1] Dong Chao;Chen Bin;Yuan Jiehao;Wang Zhendong;Wang Can(Institute of Geophysics,China Earthquake Administration,Beijing 100081,China)

机构地区：[1]中国地震局地球物理研究所,北京100081

出　　处：《地震学报》2021年第4期453-462,I0001,共11页Acta Seismologica Sinica

基　　金：中国地震局地球物理研究所基本科研业务费专项(DQJB21Y41,DQJB19B01);国家自然基金青年基金(42004049)共同资助。

摘　　要：本文利用2019年和2020年两期的全国流动地磁矢量数据,针对玛多M_(S)7.4地震震中附近的岩石圈磁场空间分布,分析研究了岩石圈磁场各个分量的震前变化特征。结果表明,玛多M_(S)7.4地震发生前,震中附近的岩石圈磁场分量均发生了不同程度的变化:震中位于各分量的弱变化区域和零变线附近;震中位于各分量的高梯度带和低梯度带之间。本文证实了地震发生前会引起岩石圈磁场变化这一现象,并总结了震前地磁分量的变化特征,为今后强地震(尤其是M≥7.0地震)的震磁关系研究提供了一个震例参考。This paper analyzes and studies the magnetic anomaly characteristics of each component of the lithospheric magnetic field in the view of pre-earthquake changes of the lithospheric magnetic field near the epicenter of the Madoi M_(S)7.4 earthquake using geomagnetic field vector data of the mainland of China in 2020 and 2019.The results show that before the Madoi M_(S)7.4 earthquake,the lithospheric magnetic field components near the epicenter all changed to varying degrees.The Madoi M_(S)7.4 earthquake epicenter is located at the weakly magnetic anomaly region,and near the zero-variation line of all the components.The Madoi M_(S)7.4 earthquake epicenter is located between the high gradient belt and the low gradient belt of all the components.This paper confirms that the lithospheric magnetic anomaly will be changed before the earthquake,and summarizes characteristics of geomagnetic components magnetic anomaly,and provides a case for the future study of the seismo-magnetism,especially the earthquakes that magnitude larger than 7.0.

关 键 词：磁场变化特征 玛多M 7.4地震 岩石圈磁场 震磁关系 

分 类 号：P315.721[天文地球—地震学]