地质通报2018，Vol.37Issue(2)：345-355,11.
东昆仑地区昆仑河韧性剪切带的识别、时代厘定及构造意义
摘要
Abstract
Along the Kunlun River of Qinghai Province in the East Kunlun Mountains,a large-scale ductile shear zone is developed. The rocks that involved in the ductile shear deformation and experienced extensive mylonitization include the metamorphosed basic to intermediate volcanic rocks, clastic rocks and marble of the Middle-Upper Proterozoic Wanbaogou Group, the metamorphosed clastic rocks,basalt and marble of the Ordovician Nachitai Group,and the Silurian intermediate to acid intrusive rocks.The structural marks observed in the shear zone,such as the σ-type rotated porphyroclasts,S-C fabrics and the asymmetrical folds of mylonite folia-tion,indicate in general a dextral strike-slip shear superimposed by a later sinistral shear.Zircon LA-ICP-MS U-Pb ages of the de-formed granodiorite and the undeformed muscovite granite in the shear zone are 432.3±1.2Ma and 423.3±1.5Ma,respectively,sug-gesting that the shear zone formed between ca. 432Ma and 423Ma. Combined with the regional tectonic evolution, it is suggested that the Kunlun River shear zone represents the tectonic response to the collisional orogeny in the Middle-Late Silurian between the North and South Kunlun blocks after the closing of the Proto-Tethys Ocean. The later sinistral shearing was controlled by the strike-slipping of the South Kunlun fault zone in the early Yanshanian period.关键词
韧性剪切带/构造变形/LA-ICP-MS锆石U-Pb年龄/构造演化/昆仑河/东昆仑Key words
ductile shear zone/tectonic deformation/LA-ICP-MS zircon U-Pb age/tectonic evolution/Kunlun River/East Kun-lun Mountains分类
天文与地球科学引用本文复制引用
顾雪祥,章永梅,冯李强,何格,王佳琳,康继祖,王秉璋..东昆仑地区昆仑河韧性剪切带的识别、时代厘定及构造意义[J].地质通报,2018,37(2):345-355,11.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) （编号:2016020003ky003）
