2013年前郭5.8级震群的地磁多方法异常分析

Geomagnetic Anomaly Analysis of Qianguo M5.8 Earthquake Swarm by Multiple Methods

收集2013年东北地区地磁分钟值观测数据,运用地磁总场绝对值北京时02点值空间相关法、地磁垂直分量日变化空间相关法、地磁垂直分量日变幅逐日比法和地磁谐波振幅比法进行计算分析,结果显示2013年11月23日前郭5.8级震群前均有异常现象出现。综合单方法的发震时间预测结果和发震地点预测表明:地震发生前,存在多种地磁分析方法异常的现象,异常数量的增多提高了各地磁分析方法异常的可信度;距离发震时间越近,异常数量有明显的增加,预示着该地区的发震概率的增大;多方法预测发震地点的综合分析,相对于单方法而言,可以缩小预测范围。

In this paper,we collect the data of geomagnetic minute values of Northeast China in 2013 to calculate and analyze by the Beijing 02 point absolute value of geomagnetic total intensity of spatial correlation,spatial correlation of daily geomagnetic variation,daily variation amplitude of geomagnetic vertical component ratio and geomagnetic harmonic amplitude ratio methods. The calculation results show that there appeared geomagnetism anomaly by 4 methods before the Qianguo M5. 8 earthquake swarm occurred on Nov. 23,2013. Adding the single method of earthquake time and location prediction analysis,the results show that there may be a variety of geomagnetic anomaly calculation analysis methods before the earthquake. The distance from the earthquake more recent,the number of anomalies increases significantly. And the number of anomalies increase,indicating the area of the earthquake probability increases. Compared with the single method,the comprehensive analysis methods of earthquake location can reduce the prediction range.