School of Earth Sciences and Resources,China University of Geosciences,Beijing 100083,China

SinoProbe Laboratory,MNR Key Laboratory of Isotope Geology,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China

Department of Geosciences,University of Arizona,Tucson AZ,USA

Xi'an Center of Geological Survey,China Geological Survey,Xi'an 710010,China