Strontium isotope geochemistry of the Lemachang independent silver ore deposit, northeastern Yunnan, China

作     者：邓海琳 李朝阳 涂光炽 周云满 王崇武 

作者机构：The Open Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China No. 1 Geological Party of the Yunnan Bureau of Geology and Mineral Resources Xundian 655205 China 

出 版 物：《Science China Earth Sciences》 (中国科学（地球科学英文版）)

年 卷 期：2000年第43卷第4期

页      面：337-346页

核心收录：

学科分类：070902[理学-地球化学] 0709[理学-地质学] 07[理学] 

主　　题：Lemachang northeastern Yunnan independent Ag deposit Sr isotope ore-forming fluid. 

摘      要：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.