Tectonic implications from Re–Os dating of Mesozoic
The basement rocks in North Qinling orogenic belt mostly comprise amphibolite and granulite facies assemblages such as biotite plagiogneiss twofeldspar granulites and graphitic marbles represented by the Qinling Group Meng and Zhang 2000 This crystalline basement is the main component of the Tongbai–Dabie metamorphic terrains