摘要
利用收集的60个震源机制解,应用MSATSI软件反演了2015年4月15日内蒙古阿拉善左旗MS5.8级地震的震中周围地区的构造应力场。结果显示:此次地震是发生在走滑体系的背景下,总体应力场的空间不均匀性表现不明显。总体最大主压应力走向N42±7°E,主张应力走向为N58±12.6°W,R值约为0.4。相比于前人的结果,该结果与地震发生震源机制的P、T轴方位更加一致。为揭示余震和主震之间的关系,计算了此次地震所造成的静态破裂库仑应力变化。结果表明:M4.0级余震的静态库仑应力变化值分别为0.042 8 MPa,M3.2级余震的静态库伦应力变化值为0.023 MPa,说明此次地震对2次余震有触发作用。
On April 15,2015,aMS5.8earthquake occurred in Inner Mongolia＇s Alxa Left Banner.60 focal mechanism solutions are collected around the epicenter.Stress field of the epicenter area is inverted by using MSATSI software.The results show that this earthquake occurred in the regime of strike-slip system.The inhomogeneity of stress field is not spatially obvious.The trend of the principal compression stress is N42±7°E and that of the principal tensional stress is N58±12.6°W.The R value is^0.4.Compared with the results of previous studies,the directions of compressional and tensional stress axes are more consistent with the P,T axes of the focal mechanism of this earthquake.In order to understanding the relationship of mainshock and aftershocks of this earthquake sequence,we calculated the static Coulomb rupture stress changes produced by this earthquake.Results show that coulomb stress changes at the epicenter of M4.0and M3.1aftershocks are 0.043 MPa and 0.023 MPa,respectively,which show the triggering effect on aftershocks of this earthquake.
出处
《华北地震科学》
2015年第2期48-54,共7页
North China Earthquake Sciences
基金
河北省地震科技星火计划(DZ20140101002)
中央高校基本科研业务专项资金(创新项目团队资助计划)(ZY20110101)
国家国际科技合作专项(2012DFR20440)
关键词
震源机制解
构造应力场
静态库仑应力变化
focal mechanism solutions
tectonic stress field
static coulomb stress changes
