日本MW9.0级地震后辽宁营口区域构造应力场研究  

STUDY ON TECTONIC STRESS FIELD IN YINGKOU AREA AFTER MW9.0 EARTHQUAKE IN JAPAN

作　　者：冯兵 王文涛 FENG Bing;WANG Wentao(The Second Monitoring And Application Center,CEA,Xi’an 710054,China)

机构地区：[1]中国地震局第二监测中心,陕西西安710054

出　　处：《高原地震》2020年第1期18-25,共8页Plateau Earthquake Research

摘　　要：本文整理了辽宁营口地区2011~2013年期间257个小震震源机制解数据,采用分区的方式利用震源机制解反演应力场的网格搜索法反演了该地区的平均应力场。反演的应力场结果显示:总区(辽宁营口地区)主压应力轴分布于北东东—南西西方向,主张应力轴分布于北北西—南南东方向,与前人研究的结果基本一致。B区(营口—海城断裂带和海城河断裂带区域)主压应力轴为北东东—南西西方向,主张应力轴为北北西—南南东方向,这与该地区的构造应力场方向相同。C区(金州断裂带区域)主压应力轴与主张应力轴方向均为北东东—南南西向。针对C区(金州断裂带区域)出现的这一异常情况,研究将地震震级ML≥3.0的震源机制解数据从总的数据中重新挑了出来,并重新将它们分区进行反演,结果显示C区(金州断裂带区域)的主压应力轴与主张应力轴方向仍为北东东—南南西向。对C区(金州断裂带区域)出现的这一异常现象,本文从断裂带分布与孕震机理的角度进行了详细的研究分析,以期对其做出合理的解释。In this paper,the focal mechanism data of 257 small earthquakes from 2011 to 2013 in Yingkou area,Liaoning Province are collected.The stress field around Yingkou was inverse,the inversion result indicates that the principal compression stress direction is NEE-SWW and the principal tension stress direction is NNW-SSE.In accordance with the previous results.Area B(Yingkou-Haicheng fault and Haicheng fault area)main compressive stress axes is NEE-SWW direction,the stress axis is the NNW-SSE direction,which is the same direction as the tectonic stress field in this region.The principal compressive stress axis of area C(Jinzhou fault zone)and the direction of stress axes is NEE-SWW direction.In view of the seismic source mechanism of earthquake magnitude MS≥3.0 was reselected from the total data.In addition,the partition was redirected and showed that the axial direction of the stress axis and the main compressive stress axis in the C region(Jinzhou fault zone)was still NEE-SSW.The paper makes a detailed research and analysis from mechanism of seismogenesis in order to make a reasonable explanation for this abnormal phenomenon in C area(Jinzhou fault zone).

关 键 词：营口市 震源机制解 应力场 主压应力 

分 类 号：P315.01[天文地球—地震学]