1977年至2006年新疆伽师地震断层性质及应力场变化原因初探  

Research of the reason for variations of the earthquake fault characters and the stress field in the Jiashi region of Xingjing from 1977 to 2006

作　　者：屠泓为[1] 万秀红[1] 高歌[2] 罗国富[3] 胡永钧 马震[1] 

机构地区：[1]青海省地震局,西宁810001 [2]新疆维吾尔自治区地震局,乌鲁木齐830011 [3]宁夏回族自治区地震局,银川750001 [4]甘肃省地震局,兰州730000

出　　处：《地球物理学进展》2008年第4期1038-1044,共7页Progress in Geophysics

基　　金：青海地震科学基金(200698A05);中国台网中心科研项目(120602-0957-03);新疆科技攻关项目(200333116)联合资助

摘　　要：自1977-2006年,新疆伽师地区相继发生了多次强地震.本文运用哈佛大学公布的该区域的CMT解,通过对不同地震的分布及断层性质的定量化分析,将地震分为三个时段,并由P,T轴拟合了该区域分时段的应力场方向,分析震源性质及区域应力场发现,1997年3月1日至2003年1月4日该区域的地震断层性质及应力场均发生了较大变化,而2003年2月24日起,其地震断层性质和应力场方向又恢复到了第一时段的状态,结合该区域地层速度模型和区域受力状况、构造背景、以及地震断层性质和分布规律等,作者提出了该区域地震断层性质及应力场变化原因是由于障碍体的存在结论.Many times of strong earthquakes occurred in the Jiashi region of Xingjing from 1977 to 2006. The CMT solutions of the region issued by Harvard University are used to analyze the regional stress field and the fault characters of the earthquakes. We divied the earthquakes into three periods,and calculate the stress field direction by P and T axes. Further analysis of the he region stress field and the fault character of the earthquakes indicates the variationa in the period Mar. 1,1997 to Jan 4,2003. Since Feb. 24,2003, the direction of the basic stress field and the fault character of the earthquakes were recovered. Combining the velocity model of stratum and the stress condition, the fault characters, earthquakes distribution,and tectonic background of the region,we suggest that there is a barrier at the reason for the variation of seismic fault charcters and the stress field.

关 键 词：新疆伽师 地震断层性质 应力场 变化原因 障碍体 

分 类 号：P315[天文地球—地震学]