U-Pb zircon ages of tianzhushan granites in the eastern dabie orogen and their geological implications

摘要

The precise U-Pb zircon dating of Tianzhushan granites indicates: the emplacement age of the intrusion is 127 Ma, It is one part of the Large-scale magmatic emplacement in the extension environment after the collision between Yangtze Block (YB) and North China Block (NCB), and is belonged to the granites formed after collision orogens. This large-scale tectonic magma event not only caused the emplacement of granitic intrusion and led to intense metamorphism and deformation of the rocks in Dabie area, but also played a very important role for the Dabie ultrahigh pressure (UHP) metamorphic rocks ultimately returning to the earth surface.