中天山北缘剪切带东段晚三叠世右旋走滑:对中亚造山带西南缘造山复活的响应  

Late Triassic Dextral Strike-Slip Deformation in the Eastern Segment of the North Central Tianshan Shear Zone:Response to an Orogenic Revival Event in the Southwestern Margin of the Central Asian Orogenic Belt

作　　者：刘博 陈正乐[1,3] 袁峰[2] 张青[1] 韩凤彬[1] 张文高[1] 霍海龙 李季霖 赵同阳 韩琼 李平 夏冬 屈梦梦 Liu Bo;Cheng Zhengle;Yuan Feng;Zhang Qing;Han Fengbin;Zhang Wengao;Huo Hailong;Li Jilin;Zhao Tongyang;Han Qiong;Li Ping;Xia Dong;Qu Mengmeng(Key Laboratory of Paleomagnetism and Tectonic Reconstruction of Ministry of Land and Resources,Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing,100081,China;School of Resources and Environmental Engineering,Hefei University of Technology,Hefei,,Anhui 230009,China;State Key Laboratory of nuclear resources and environment,East China University of Technology,Nanchang,Jiangxi,330013,China;Xinjiang Institute of Geological Survey,Urumqi,Xinjiang,830000,China)

机构地区：[1]国土资源部古地磁与古构造重建重点实验室,中国地质科学院地质力学研究所,北京100081 [2]合肥工业大学资源与环境工程学院,安徽合肥230009 [3]核资源与环境国家重点实验室,东华理工大学,江西南昌330013 [4]新疆维吾尔自治区地质调查院,新疆乌鲁木齐830000

出　　处：《新疆地质》2022年第1期85-91,共7页Xinjiang Geology

基　　金：国家科技支撑计划项目(2018YFC0604005);中国核工业地质局项目(201907-4);中国地质调查局项目(DD20190161);国家自然科学基金项目(41902214)联合资助。

摘　　要：中天山北缘剪切带东段位于东天山地区,是重塑中亚造山带西南缘演化过程的关键断裂之一。在雅满苏南,中天山北缘剪切带东段韧性变形强烈。野外观测和镜下观察表明,剪切带具有典型的右旋走滑特征。糜棱岩化片岩的绢云母^(40)Ar/^(39)Ar坪年龄为(211.5±1.3)Ma,说明该变形事件发生在晚三叠世。进一步综合区域资料分析认为,中天山北缘剪切带东段晚三叠世的韧性走滑是对中亚造山带西南缘聚合后再次复活造山的响应;中亚造山带西南缘晚三叠世复活造山时限为230~210 Ma,其动力主要来自于NWW方向的波罗的海克拉通的挤压。The eastern segment of the North Central Tianshan Shear Zone,located in the Eastern Tianshan area,is one of the key faults to understand the evolution processes of the southwestern margin of the Central Asian Orogenic Belt.In southern Yamansu,the eastern part of the shear zone in the northern margin of the Middle Tianshan Mountains has strong ductile deformation.Field and microscopic observations show that the shear zone is characterized by dextral strike-slip deformation.The ^(40)Ar/^(39)Ar dating of sericite from a mylonitic schist yields an age of 211.5±1.3Ma,indicating that the deformation event occurred in the Late Triassic.Further analyses of regional data suggest that the Late Triassic strike-slip in this shear zone should be a response to an orogenic revival event in the southwestern margin of the Central Asian Orogenic Belt.The Late Triassic revival orogeny time in the southwest margin of the Central Asian Orogenic Belt is 230~210 Ma.Its driving force mainly comes from the compression of the Baltic craton in the NWW direction.

关 键 词：中天山北缘剪切带 中亚造山带西南缘 ^(40)Ar/^(39)Ar定年 晚三叠世 右旋走滑 

分 类 号：P534.51[天文地球—古生物学与地层学] P542[天文地球—地质学]