金寨震群序列特征参数一致性研究

Research on the Consistency of Characteristic Parameters of Jinzhai Earthquake Swarm Sequence

利用Snoke方法和CAP方法反演2014-08~2015-03间14次ML≥3.0地震的震源机制解,分析震源参数的时空变化特征;同时使用PTD初至震相方法计算14次地震的震源深度,并与CAP深度搜索法的结果进行对比。结果表明,金寨震群序列密集分布在115.50°~115.53°N、31.50°~31.53°E范围内,在时间和空间上均无明显的发震规律;14次ML≥3.0地震的震源机制解基本一致,P轴方位角与倾角较为一致,为近NS向水平拉张和近EW向水平挤压作用下的走滑型地震;2种方法计算获得的震源深度结果相近,集中在2~5 km。

This paper used Snoke method and cap method to inverse the focal mechanism solutions of the 14 earthquakes from August 2014 to March 2015,and analyzes the temporal and spatial changes.At the same time,we calculate the 14 ML≥3.0 earthquakes by the PTD first arrival method,and compare the results with CAP depth search method.The results show that the 2014 Jinzhai earthquake swarm sequence is densely distributed between 115.50°-115.53°N,31.50°-31.53°E,with no obvious seismogenic law in the time and space.The focal mechanism solutions of the 14 ML≥3.0 earthquakes are basically the same,the azimuth of P axis is relatively consistent,and the dip angle is relatively high.It’s a strike-slip earthquake under the action of horizontal compression near EW direction and horizontal tension near NS direction.The results obtained by the two methods are similar,focusing on 2 to 5 km.