九江—瑞昌M_s5.7地震前后地磁场水平分量异常追踪与分析

Tracing and analyzing anomalies of horizontal geomagnetic component before and after the M_s5.7 Jiujiang-Ruichang earthquake

本文利用九江瑞昌Ms5.7地震前后四期(震前一期,震后三期)地磁场三分量绝对测量观测数据,建立了震区四个不同时期地磁基本场水平分量的曲面样条模型,通过上述模型详细地追踪了九江瑞昌地震前后地磁基本场水平分量异常演变过程,分析了九江瑞昌地磁基本场水平分量异常的出现、衰减与九江—瑞昌地震的对应关系,并结合震区居里面埋深剖面图初步探讨了九江瑞昌Ms5.7地震的动力学背景.

By using the four-phases geomagnetic vector data before and after the Ms5. 7 Jiujiang-Ruichang earthquake, we established the surface spline models of geomagnetic horizontal component in four periods. By comparing the above four models, we traced evolution processes of geomagnetic horizontal component before and after the Ms 5.7 Jiujiang- Ruichang earthquake and analyzed the relations between the occurrence and attenuation of geomagnetic anomalies and the earthquake.