Strontium isotope geochemistry of the Lemachang independent silver ore deposit, northeastern Yunnan, China |
| |
| Authors: | DENG Hailin LI Chaoyang TU Guangzhi ZHOU Yunman WANG Chongwu |
| |
| Institution: | 1. The Open Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China
2. No. 1 Geological Party of the Yunnan Bureau of Geology and Mineral Resources, Xundian 655205, China |
| |
| Abstract: | Sr isotope geochemical studies (the87Sr/86Sr and δ18O-87Sr/86Sr systems) on the wall rocks and ores from the Lemachang independent Ag deposit in northeastern Yunnan provide strong evidence
that the ore-forming fluids had flown through radiogenetically Sr-enriched rocks or strata prior to their entry into the locus
of ore precipitation, and water-rock interaction is the main mechanism of Ag ore precipitation. The radiogenetically Sr-enriched
source region may be the Proterozoic basement (the Kunyang and Hekou groups). Moreover, the theoretical modeling of the Sr
isotopic system indicates that the ore-forming fluids contain as much as 3×10-6 Sr with isotopic composition of Sr being 0.750 and that of oxygen 7.0‰ The ore-forming temperatures were estimated at 150–250°C
for the carbonate rock-type ores and at 200–260°C for the clastic rock-type. |
| |
| Keywords: | Lemachang northeastern Yunnan independent Ag deposit Sr isotope ore-forming fluid |
| 本文献已被 万方数据 SpringerLink 等数据库收录！ |
