滇西北安乐铅锌矿床流体包裹体研究

Fluid Inclusions of the Anle Pb-Zn Deposit in Northwestern Yunnan Province,China

安乐铅锌矿床位于三江地区的中甸断凹,是滇西北地区一处重要的铅锌矿。本文通过对该矿床与矿石密切共生的石英中流体包裹体的类型、特征、均一温度、盐度、密度、成矿压力以及流体包裹体中气液相成分的分析,探讨了流体性质、演化及矿床成因。结果表明,该区流体主要属于CO2-H2O-NaCl体系,均一温度范围在130～370℃之间,盐度在3.00%～12.75%NaCl之间,由成矿压力推算的成矿深度为1.37～3.77 km。矿床特征及包裹体特征与造山型矿床相似,推测该矿床属于"同造山"构造体制下发育的成矿系统。

The Anle Pb-Zn deposit, located in the Zhongdian rift of the Three Rivers, northwest Yunnan Province, is one of the important Pb-Zn deposits in China. Based on the study of the fluid inclusions in quartz closely associated with the ore deposit, including the types, characteristics, homogenization temperature, salinity, density, pressure and gaseous-liquid compositions, the characteristics of ore-forming fluid, fluid evolution and the origin of the Anle Pb-Zn deposit were detailedly discussed. The results show that the ore-forming fluids in the area mainly belong to CO2-H20-NaC1 system, with the homogenization temperature of 130 - 370°C and salinity of 3.00% - 12. 75%. The mineralization depth of the deposit is deduced to be 1.37 - 3.77 km according to the ore-forming pressure. Be- cause the similar mineralization types and fluid inclusions characteristics between Anle Pb-Zn deposit and the orogen- ic-type deposits, the Anle Pb-Zn deposit may be associated with synorogenie tectonic process.