西北地质Issue(3)：1-7,7.
青海玉龙滩地区托赖岩群中-早二叠世基性岩墙的发现及地质意义
Discovery and Geological Significance of Early Permian Mafic Dike Rock of Yulongtan Region Which Intrusive into Tuolai Paleo-Proterozic Rock
摘要
Abstract
A set of basic dyke intrusion has been found in metamorphic rocks of Tuolai Paleoproterozoic rock group in Yulongtan Region.Gabbro vein and diabasic dyke are found to be the main intrusive rocks and they intruded into the gneiss and schist of Tuolai rock group.The axes of the dykes are mostly NW,with a few close to SN or NE,the outcrop scale is within 10-35m in length and 5-10m in width.Isotope dating analysis on diabasic dyke shows its geological age as early Permian.Combined with its geological features,petrology,petrochemistry and geochemistry characteristics,it is suggested that the dyke belongs to tholeiitic series and forms in extensional tectonic setting.Considering the regional geological analysis,it is concluded that after Caledonian orogeny,Qilianshan orogenic belt had experienced a stretch and collapse due to the thickening of continental crust,and the process led to the underplating of basic mantle-derived magma,thus formed the basic dyke.It is reflected that in early Permian a basic magma underplating event occurred with continental crust thickening and extension in north Qilian area.关键词
北祁连/基性岩墙/早二叠世/伸展裂解Key words
north Qilian Mountains/basic dyke/Early Permian/extension and collapse分类
天文与地球科学引用本文复制引用
张金明,才航加,陈光庭..青海玉龙滩地区托赖岩群中-早二叠世基性岩墙的发现及地质意义[J].西北地质,2014,(3):1-7,7.基金项目
青海1∶5万玉龙滩、抓什究、贺尔、桥头幅区调(1212011121192) （1212011121192）
