鲜水河断裂跨断层异常与九寨沟地震关联性探讨  

Discussion on the Correlation between Cross-Fault Abnormality of the Xianshuihe Fracture and the Jiuzhaigou Earthquake

作　　者：张希[1] 秦姗兰[1] 郝明[1] 李瑞莎[1] ZHANG Xi;QIN Shanlan;HAO Ming;LI Ruisha(The Second Monitoring and Application Center,CEA,316 Xiying Road,Xi’an 710054,China)

机构地区：[1]中国地震局第二监测中心

出　　处：《大地测量与地球动力学》2019年第10期991-996,共6页Journal of Geodesy and Geodynamics

基　　金：中国地震局地震预测研究所基本科研业务费专项（2016IES0102）~~

摘　　要：提取巴颜喀拉地块东部边界鲜水河断裂、龙门山断裂及边界附近西秦岭构造区跨断层灰色关联度指标曲线,根据1999~2007年、2009~2015年及2015~2017年GPS速度场数据计算所得的鲜水河断裂、龙门山断裂及塔藏断裂剖面变化,通过对比分析寻找地块边界断裂活动的共性特征。结果表明,2009年巴颜喀拉地块东部出现显著的SE向加速运动,之后数年一直维持这种高速特性,汶川8级地震的发生调整了该地区的应力状态,有利于芦山7级地震及九寨沟7级地震的发生;2015~2017年巴颜喀拉地块东部在维持高速运动和高应力状态基础上继续增速变化,地块边界鲜水河断裂2016~2017-07跨断层观测数据显示的显著拉张加速变化与九寨沟地震有一定关联,具中期背景性预测意义。In this paper,the grey correlation index curves of the Xianshuihe fault,Longmenshan fault and the western Qinling mountains tectonic area at or near the boundaries of Bayan Har block are extracted.The section variations of Xianshuihe fault,Longmenshan fault and Tazang fault are calculated from GPS velocity field data during 1999-2007,2009-2015,2015-2017.We compare and analyze the common characteristics of the fault activity of the block boundary.The results show that the SE-trending movement acceleration began to appear in the east of Bayan Har block in 2009,and that this high-speed characteristic has been maintained for several years.The occurrence of Wenchuan M8.0 earthquake adjusted the stress-strain state of this area,which supports the occurrence of Lushan and Jiuzhaigou M7.0 earthquakes.On the basis of maintaining high-speed movement and high stress-strain state in the east of Bayan Har block from 2015 to 2017,and then accelerating slightly,the remarkable acceleration of tension observed by cross-fault observation of Xianshuihe fault in the boundary of the block from 2016 to July 2017 is related to the Jiuzhaigou earthquake,which is significant for medium-term background prediction.

关 键 词：鲜水河断裂 跨断层形变异常 九寨沟地震 GPS资料 

分 类 号：P315[天文地球—地震学]