基金Two anonymous reviewers are thanked for their constructive comments and suggestions. We also thank Wu Jianxun and Zhou Sen for their assistance with field sampling and Xiao Guoqiao （associate pro- lessor at CUG-Wuhan） for his valuable suggestions. James Ogg （professor at CUG-Wuhan and Purdue University of USA） polishedportions of the Eng- lish version of this work and advised on aspects of thepresentation. The U-Pb age data in this article can be obtained by sending email to us. This work was supported by National Natural Science Foundation of China （Grant Nos. 41572339, 41002051 ＆ 41322013） and Fundamental Research Funds for the Central Universities, China University of Geosciences （Wuhan） （Grant No. CUG160217）.