2010年玉树M_S 7.1地震发震断层面参数的确定  

The fault plane parameter determination of the 2010 Yushu M_S 7.1 earthquake

作　　者：盛书中[1,2] 万永革[1,2] 王未来[2] 郑爽 石砚斌[1] 李迎秋[1] 

机构地区：[1]防灾科技学院,三河065201 [2]中国地震局地球物理研究所,北京100081 [3]宽城地震台,承德067000

出　　处：《地球物理学进展》2014年第4期1555-1562,共8页Progress in Geophysics

基　　金：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);地震行业专项(201208009);国家自然科学基金(41074072)共同资助

摘　　要：本研究将利用余震分布和区域应力场确定大震断层面参数的方法应用于2010年玉树MS7.1级地震发震断层面参数的确定,获得了本次地震断层面参数为:走向294.6°,倾角78.0°,滑动角7.5°,属于左旋走滑型地震和甘孜—玉树断裂带的性质相一致.主震前后应力场反演结果表明该区域的应力场为:中间主应力轴近直立,最大和最小主应力轴近水平,且发现玉树地震前后震源区应力场存在偏转现象,最大主压应力轴由震前的NEE向逆时针旋转至震后的NNE向,震后最大主压应力轴与断层走向近垂直,表明主震对震源区应力释放较为充分.Based on the aftershock distribution and the regional stress field,we obtained the fault plane parameters of the 2010 Yushu MS7.1 earthquake,the fault plane parameter are as follows：the strike is 294.6°,the dip angle is 78.0°,the slip angle is 7.5°,this shows that the seismic fault is a left-lateral strike-slip fault,this results consistent with the property of Garzê-Yushu fault.The stress field inversion results of preseismic and post-seismic shows that the intermediate principal stress axes is nearly vertical,the maximum and minimum principal stress axes are nearly horizontal,we detect that the maximum principal stress axes strikes NEE before the Yushu earthquake,and it anti-clockwise rotates to NNE after the Yushu earthquake,the maximum principal stress axes nearly perpendicular to the strike of Garzê-Yushu fault after the Yushu earthquake,this may indicates that the stress release of the mainshock in the focal area is completely.

关 键 词：玉树地震 余震 断层面参数 应力场 应力偏转 

分 类 号：P315[天文地球—地震学]