柯坪块体周缘主要断裂闭锁程度与滑动亏损速率的分布特征  

Distribution Characteristics of Locking Fraction and Slip Deficit Rate along Main Faults around Keping Block

作　　者：李瑞 李杰[1,2] 刘代芹 苏力坦·玉散[1,2] 李桂荣[1,2] 孙小旭 艾力夏提·玉山 Li Rui;Li Jie;Liu Daiqin;Sulitan·Yusan;Li Guirong;Sun Xiaoxu;Ailixiati·Yushan(Urumqi Institute of Seismology in Central Asia,China Earthquake Administration,Urumqi 830011,China;Earthquake Agency of Xinjiang Uygur Autonomous Region,Urumqi 830011,China)

机构地区：[1]中国地震局乌鲁木齐中亚地震研究所,乌鲁木齐830011 [2]新疆维吾尔自治区地震局,乌鲁木齐830011

出　　处：《中国地震》2021年第4期868-877,共10页Earthquake Research in China

基　　金：地震科技星火计划(XH20069Y、XH18054);国家自然科学基金(41874015)共同资助。

摘　　要：利用西南天山山前柯坪块体周缘的多期中国大陆构造环境监测网络区域站及新疆维吾尔自治区地震局在该区域加密布设的多个GPS站点数据,基于负位错反演原理,采用Defnode软件反演,得到柯坪、皮羌和迈丹3条主要断裂的闭锁程度和滑动亏损速率分布特征。模拟结果与实测值总体一致,但略有细微差异,GPS点位密集处残差在1mm/a左右,柯坪断裂在深度20km以内处于完全闭锁,20~40km之间处于部分蠕滑,40km以下处于完全蠕滑;皮羌断裂全段在深度15km以内处于完全闭锁,15~30km之间处于部分蠕滑,30km以下处于完全蠕滑,滑动亏损速率介于0~2mm/a;迈丹断裂闭锁系数与滑动亏损速率分布特征相对复杂,完全闭锁深度从西南端的35km逐渐递减至东北端的10km左右。上述研究结果为分析评估3条断裂的地震危险性提供了观测约束,对认识该地区的地震孕育背景及地震危险性研究提供参考依据。Using multi-period GSP observation data from“Crustal Movement Observation Network of China”and from GPS stations installed by the earthquake agency of Xnjiang Uygur Autonomous Region in the Keping block area located in the southwest Tianshan mountain,we calculated and obtained the distribution characteristics of locking fraction and slip deficit rate of the three major faults of Keping,Piqiang and Maidan around the Keping block by applying inversion calculation software—Defnode based on the principle of negative dislocation inversion.The calculated result by the inversion software is consistent with the actual observed data with the residual error about 1mm in the places with dense GPS sites.The results shows that keping fault has a stable change in fault locking,with a complete locking depth within 20km,a partial fault locking between 20km and 40km,and a fully creeping state below 40km.The Piqiang Fault has a fault locking depth of less than 10km,a partial locking state between 10km and 30km,and a fully creeping state below 30km,in which the slip deficit rate is between 0 and 2 mm/a.The fault locking situation of the Maidan fault is complicated,in which the fault locking depth gradually decreases from the southwest segment to the northeast end,and gradually decreases from 35km to less than 10km.

关 键 词：柯坪块体 陆态网络 Defnode 闭锁系数 滑动亏损速率 

分 类 号：P315[天文地球—地震学]