内蒙古中部凉城地区紫苏斜长麻粒岩锆石U-Pb年龄及地质意义

基金项目: 中国地质调查局1∶25万区域地质调查修测项目（1212011120751）资助。

Zircon U-Pb dating of the hypersthene-plagioclase granulite in Liangcheng area of central Inner Mongolia and its geological significance

1.
Inner Mongolia Institute of Geological Survey and Mineral Exploration, Hohhot 010010, Inner Mongolia, China
2.
Institute of Geological and Mineral Exploration of Central South Jiangxi, Nanchang 330002, Jiangxi, China

摘要: 提要：对内蒙古中部凉城地区的紫苏（二辉）斜长麻粒岩进行了同位素地质年代学、岩石学和岩石地球化学研究，探讨了其形成时代和构造背景。利用LA-ICP-MS 锆石U-Pb法测得紫苏斜长麻粒岩岩体的年龄为（1935±9）Ma，属古元古代；研究表明该岩体形成于板内构造环境，在19亿年左右，研究区有地幔上涌并伴随玄武质岩浆的底侵作用，底侵玄武质岩浆作为岩体在下地壳就位，并发生麻粒岩相变质作用。
- 锆石U-Pb年龄 /
- 紫苏（二辉）斜长麻粒岩 /
- 内蒙古中部凉城地区
Abstract: Abstract: Geochronology, petrology and petro-geochemistry of hypersthene-plagioclase granulite from Liangcheng area of central Inner Mongolia were investigated, and its forming age and tectonic background were discussed. The age of hypersthene-plagioclase granulite dated by LA-ICP-MS U-Pb of zircons is (1935±9) Ma, indicating that it was formed in Paleoproterozoic. Research shows that the rock mass was formed in a plate tectonic environment, the study area experienced mantle upwelling accompanied by underplating basaltic magma about 19 billion years ago, and the basaltic magma was intruded into the lower crust and caused the granulite facies metamorphism.
- U-Pb zircon age /
- hypersthene-plagioclase granulite /
- Liangcheng area of central Inner Mongolia