Re-Os Dating of Galena and Sphalerite from Lead-Zinc Sulfide Deposits in Yunnan Province, SW China  

作　　者：Yingying Liu Liang Qi Jianfeng Gao Lin Ye Zhilong Huang Jiaxi Zhou 

机构地区：[1]State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences [2]University of Chinese Academy of Sciences

出　　处：《Journal of Earth Science》2015年第3期343-351,共9页地球科学学刊（英文版）

基　　金：supported by the 12th Five-Year Plan Projects of State Key Laboratory of Ore Deposit Geochemistry, Chinese Academy of Sciences (Nos. SKLODG-ZY125-09, SKLODG-ZY125-02);the National Natural Science Foundation of China (Nos. 41373064, 41102053 and 41163001);the Science and Technology Plan Project of Yunnan Province (No. 2009CD029)

摘　　要：Dating of lead-zinc deposits is of critical importance for better understanding of ore genesis, but has long been a big challenge due to the lack of suitable minerals that can be unequivocally linked to the ore genesis and that can be used for tradition radiometric methods. This kind of deposits have simple mineralogy dominated by galena and sphalerite commonly associated with calcite and other gangue minerals. Both galena and sphalerite have low and high variable Re concentrations and thus Re-Os dating of these minerals have been less promising. In addition, the recovery of Re is extremely low for galena when conventional method was applied, lending additional difficulty in precisely dating galena. In this study, we investigate the recovery of Re using different media for anion exchange separation and reporte a revised preparation method for Re-Os dating of galena and sphalerite. By using the new protocol, two reliable Re-Os isochron ages of galena and sphalerite from the Fule（20.4±3.2 Ma） and Laochang（308±25 Ma） Pb-Zn deposits in Yunnan Province, SW China, are achieved.Dating of lead-zinc deposits is of critical importance for better understanding of ore genesis, but has long been a big challenge due to the lack of suitable minerals that can be unequivocally linked to the ore genesis and that can be used for tradition radiometric methods. This kind of deposits have simple mineralogy dominated by galena and sphalerite commonly associated with calcite and other gangue minerals. Both galena and sphalerite have low and high variable Re concentrations and thus Re-Os dating of these minerals have been less promising. In addition, the recovery of Re is extremely low for galena when conventional method was applied, lending additional difficulty in precisely dating galena. In this study, we investigate the recovery of Re using different media for anion exchange separation and reporte a revised preparation method for Re-Os dating of galena and sphalerite. By using the new protocol, two reliable Re-Os isochron ages of galena and sphalerite from the Fule（20.4±3.2 Ma） and Laochang（308±25 Ma） Pb-Zn deposits in Yunnan Province, SW China, are achieved.

关 键 词：lead-zinc sulfide deposits Re-Os isotope dating separation and concentration of Re GALENA SPHALERITE YUNNAN 

分 类 号：P618.4[天文地球—矿床学]