1. Chongqing University of Science and Technology; Chongqing 401331 China
2. State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry; Chinese Academy of Sciences; 99 West Lincheng Road Guiyang 550081 China
3. University of Chinese Academy of Sciences; Beijing 100049 China
4. Institute of Sedimentary Geology; Chengdu University of Technology; Chengdu 610059 Sichuan China