国家自然科学基金项目40921001、41430212、41202153、41472198;中国地质调查局项目1212010818094、12120115026801、D1515-2;国土资源部公益性行业基金项目编号:201511022、201211093联合资助的成果.This study was supported by the National Natural Science Fondation of China40921001,41430212,41202153,41472198;the Geological Survey of China 1212010818094,12120115026801,D1515-2 as well as commonweal fund projects of Ministry of Land and Resources of China201511022,201211093