地质通报2017，Vol.36Issue(6)：987-1000,14.
东昆仑南缘韧性剪切带变形特征及其形成时代的限定
Age and structural deformation of ductile shear zones on the southern margin of the East Kunlun Mountains
摘要
Abstract
As a result of oblique subduction of the Bayan Har-Songpan-Garze terrane toward the East Kunlun terrane in Mesozoic,a major ductile shear zone formed along the southern margin of the East Kunlun terrane.Ductile deformation phenomena observed in the ductile shear zones,such as porphyroclasts,porphyroclastic structure,cleavage-step,mica fish,S-C fabric,asymmetrical folds and echelon veins,implying both dextral and sinistral shear characteristics.The dextral shear is earlier than the sinistral shear.However,the sinistral shear is the dominant feature in these ductile shear zones.LA-ICP-MS U-Pb dating of zircons from the mylonitization granite in Xidatan and the undeformed granite in Xiaonanchuan yielded ages of 199.3±2.2Ma and 196.4± 1.3Ma,respectively.Zircons dated here are typically formed via magma crystallization,which means that their ages could represent the emplacement time of the two plutons.The deformation degree of the two pluton,which is completely different from each other,indicates that the southern margin of the East Kunlun left-lateral ductile shear zone should have formed in 199～196Ma.关键词
韧性剪切带/构造变形/LA-ICP-MS锆石U-Pb年龄/东昆仑南缘Key words
ductile shear zone/structural deformation/LA-ICP-MS zircon U-Pb age/South margin of the East Kunlun Mountains分类
天文与地球科学引用本文复制引用
冯李强,顾雪祥,章永梅,何格,康继组..东昆仑南缘韧性剪切带变形特征及其形成时代的限定[J].地质通报,2017,36(6):987-1000,14.基金项目
青海省地质勘查基金项目《青海省昆仑河地区金多金属矿整装勘查区找矿部署研究》(编号:2016020003ky003)和国家自然科学基金项目《新疆西天山吐拉苏浅成低温热液-斑岩型金成矿系统物质与时空结构研究》(批准号:41572062)、《内蒙古哈达门沟-柳坝沟金矿床碱交代作用与金钼成矿关系研究》(批准号:41302064) （编号:2016020003ky003）
