玉树M_S7.1地震地表破裂带及其同震位移分布  

Surface Rupture and Coseismic Displacement of the Yushu M_S7.1 Earthquake,China

作　　者：张军龙[1] 陈长云[1] 胡朝忠[1] 杨攀新[1] 熊仁伟[1] 李智敏[2] 任金卫[1] 

机构地区：[1]中国地震局地震预测研究所,北京100036 [2]青海省地震局,青海西宁810001

出　　处：《地震》2010年第3期1-12,共12页Earthquake

基　　金：国家重点基础研究发展计划项目(2008CB42570)资助

摘　　要：2010年4月14日青海省玉树县发生MS7.1地震,野外地质考察及室内遥感解译表明地震形成反"L"形地表破裂,长约50公里,宏观震中位于郭央烟宋多(33°3′N,96°51′E)。总体上可分为三段,北段与中段间有16km未发现明显地表破裂形迹,中段和南段呈左阶排列,阶区内发育有右阶羽列式破裂。玉树地震最大位移量不小于1.3m,以左行走滑活动为主,兼有挤压逆冲活动。玉树断裂是本次地震的发震断层,断裂南侧羌塘块体和北侧巴颜喀拉块体差异运动导致了玉树地震的发生。地震复发间隔108～185a。破裂南端与1896年强震破裂之间尚有20余公里未发现破裂,其地震危险性还有待进一步研究。On April 14,2010,a devastating MS7.1 earthquake happened in Yushu County,Qinghai Province.Field geological investigation and remote sensing interpretation show that this earthquake generated an inverse L-type surface rupture of about 50 km,with a maximum displacement of no less than 1.3 m.The surface rupture can be divided into three parts：We found no obvious rupture traces for a long distance of 16km between the northern and middle part;the middle and the southern part showed a left-step arrangement,local features of each part presented a characteristic of right-step pinnate arrangement.The seismogenic Yushu fault is dominated by strike-slip motion,with a small amount of reverse component.Differential movement between the southern Qiangtang block and northern Bayankala block caused this earthquake.Earthquake recurrence period is 185~108 a.Along an approximately 20 km part of Ganzi-Yushu fault,between the southern surface rupture of Yushu MS7.1 earthquake and the 1896 earthquake,no surface rupture has been found,its seismic risk needs further research.

关 键 词：玉树地震 地表破裂 同震位移 左行走滑 复发间隔 

分 类 号：P315.7[天文地球—地震学]