2019年长宁6.0级与夏河5.7级地震前的地磁日变化异常

Geomagnetic Diurnal Variation Anomalies Before 2019 Changning M6.0 Earthquake and Xiahe M5.7 Earthquake

运用地磁低点位移、地磁加卸载响应比和地磁逐日比三种地磁日变化异常分析方法,分析了2019年6月17日长宁6.0级和10月28日夏河5.7级地震前的地磁前兆异常现象。研究发现,两次地震前三种方法分析的结果均出现了异常,两次地震均发生在异常集中交汇区域。综合分析表明,应用地磁低点位移、加卸载响应比和逐日比预测区叠加法可以提高震中位置预测的准确度。

In this paper,we use three analysis methods of geomagnetic diurnal-variation anomaly,the geomagnetic low-value displacement,the geomagnetic load-unload response ratio and the geomagnetic daily ratio,to analyze the geomagnetic precursor anomalies before Changning M6.0 Earthquake on June 17,2019 and Xiahe M5.7 Earthquake on October 28,2019.We found that the results of all of the three methods had abnormal phenomena before Changning M6.0 and Xiahe M5.7 earthquakes,and both earthquakes occurred at the joint region of anomalies.The result shows that the superposition method of prediction of geomagnetic load-unload response ratio and geomagnetic daily ratio anomlies,as well as geomagnetic low-value displacement,can effectively improve the accuracy of epicenter prediction.