由多个震源机制解分析民乐Ms6.1级地震前后应力场演化  

ANALYSIS ON STRESS FIELDS BEFORE AND AFTER MINLE Ms 6.1 EARTHQUAKE FROM A NUMBER OF FOCAL MECHANISM SOLUTIONS

作　　者：张辉[1] 刘小凤[1] 赵凌云[1] 

机构地区：[1]中国地震局兰州地震研究所,甘肃兰州730000

出　　处：《高原地震》2007年第3期6-9,20,共5页Plateau Earthquake Research

摘　　要：2003年10月25日在甘肃省民乐县和山丹县境内发生了Ms6.1与Ms5.8级地震,对震区200km范围、震前2年内发生的地震,及对震后部分余震矩张量反演得到它们的震源机制解,并对其进行统计分析得到该区的背景应力场及应力轴的整体特征,根据发震区地质构造背景和对平均应力场变化分析,寻求民乐地震的发震机制。Ms6.1 and Ms5.8 earthquakes occurred in Minle county and Shandan county, Gansu province on Oct. 25,2003. In the paper, we use the method of moment tensor reversion to get the earthquakes＇ focal mechanism in the range of 200 km and 2 years before the main shock and portion of the aftershocks. And analyzed on the some earthquakes＇ focal mechanism solutions before and after the main shock, we get the whole characteristics of background of regional stress fields and stress axis, and get the focal mechanism of the Minle earthquake on the base of analysis on the structure of epicenter area and variety of mean stress fields.

关 键 词：震源机制解 余震 应力场 

分 类 号：P315.33[天文地球—地震学]