2017年精河MS6.6地震前地磁异常特征分析

Analysis on Geomagnetic before the Jinghe MS6.6 earthquake in 2017

摘要:

2017年8月9精河发生M_S6.6地震，距震中300km范围内的温泉台、克拉玛依台、乌鲁木齐台捕捉到此次地震前的地磁异常信息，本文对此进行了分析和总结，结论如下：①地磁谐波振幅比反应了观测点深部电阻率变化，2016年呼图壁M_S6.2、此次精河M_S6.6地震均发生在克拉玛依台地磁谐波振幅比异常下降之后的转折和恢复阶段；②震前83天、21天沿北天山断裂带分布的地磁台站逐日比和加卸载响应比均成组出现超限的高值，且异常高值的空间分布与震中位置有一定关联；③全国大陆地磁台站震前34天出现低点位移突变分界线，且异常集中于震中附近。

Abstract:

The comprehensive character of geomagnetic anomaly in the Jinghe M_S6.6 earthquake on August 9, 2017 has been summed up and analysed with geomagnetic Z component daily ratio, geomagnetic load-unload response ratio, harmonic wave amplitude ratio, geomagnetic low-point time, morphological analysis methods. It is found that the geomagnetic showed obvious middle-and short-term anomalies.