This work was supported by the National Natural Science Foundation of China (grant No. 41603034) and China Geological Survey project (grants No. DD20160019 and DD20160074). We thank all the colleagues involved in the field mapping during 2014 to 2016, particularly Hu Ling, Li Hai, Gan Lu, Zhou Xiong, Tang Deqiang and He Wenjing. Dr. Gong Huadong and Dr. Bao Zhi’an are greatly appreciated for their assistance with the LA-ICP-MS U-Pb and Lu-Hf isotopes analyses.