内蒙古武川西乌兰不浪高级区岩石及其形成环境

西乌兰不浪高级变质的兴和岩群是1:5万、1:25万区域地质调查时从海西期岩体和五台群中重新厘定出来的地质体.通过野外宏观地质特征、岩石化学、地球化学等综合分析,认为西乌兰不浪地区高级区岩石不只是由表壳岩组成,还有大量的TTG岩系、紫苏花岗岩、脉岩和岩墙,它们是不同构造环境、不同时代的构造拼合体.其中表壳岩称为兴和岩群,为一套火山-沉积岩系,形成于活动大陆边缘.

Metamorphic Petrology and Tectonic Setting of the Xi-Ulanbulang High-Grade Terrain, Wuchuan County, Inner Mongolia

The Xi-Ulanbulang high-grade terrain is located in the northwest of Wuchuan County, Inner Mongolia, in which the Xinghe Rock-group is distinguished out from the original Variscian magmatic rocks and the Archean Wutai Group. Through the integration of field investigation, petrochemical and geochemical analysis,it is thought that the Xi-Ulanbulang high-grade terrain consists of not only supracrustal rocks, but also lots of TTG, charnockite and dyke rocks, which implicates to be a tectonic assemblage of various rocks with different setting and time. Among the assemblage, the supracrustal rocks named the Xinghe Rock-group is composed of volcano-sedimentary rocks that formed in mobile continental margin. These rocks underwent intensive thermal-tectonic event, metamorphosed into high-amphibolite to granulite facies.