广西栗木锡铌钽多金属矿床成矿流体包裹体特征

Characteristics of mineralizing fluid inclusion in Sn-Nb-Ta polymetallic deposit in Limu of Guangxi

综合研究广西栗木矿田香粉厂、老虎头、牛栏岭、金竹源矿床矿石中的石英流体包裹体,结果表明,成矿热液矿物中的原生流体包裹体类型主要为纯液相包裹体,其次为气液两相包裹体。香粉厂矿床流体包裹体的均一温度平均值为203.5℃,盐度为5.54wt%NaCl,密度0.885g/cm3,压力为55.31MPa,成矿深度为5.94km;老虎头矿床流体包裹体的均一温度平均值为168℃,盐度为6.50wt%NaCl,密度0.934g/cm3,压力为46.72MPa,成矿深度为5.42km;牛栏岭矿床流体包裹体的均一温度平均值为187℃,盐度为5.03wt%NaCl,密度0.919g/cm3,压力为46.00MPa,成矿深度为5.37km;金竹源矿床流体包裹体的均一温度平均值为178℃,盐度为5.54wt%NaCl,密度0.913g/cm3,压力为48.42MPa,成矿深度为5.51km,总体属中低温度、低盐度、中等密度的体系;表明该矿床形成于中深成环境。

Based on a study of fluid inclusions in quartz from Xiangfenchang,Laohutou,Niulanling and Jinzhuyuan deposits in Limu orefield of Guangxi,it is observed that primary fluid inclusions in hydrothermal ore-forming minerals are mainly pure liquid phase inclusions and some gas-liquid phase inclusions.In Xiangfenchang deposit,the average homogenization temperature of fluid inclusion is 203.5℃,the salinity is 5.54wt%NaCl,the density is 0.885g/cm3,the pressure is 55.31MPa,and the ore-forming depth is 5.94km;in Laohutou deposit,the average homogenization temperature of fluid inclusion is 168℃,the salinity is 6.50wt%NaCl,the density is 0.934g/cm3,the pressure is 46.72MPa,and the ore-forming depth is 5.42km;in Niulanling deposit,the average homogenization temperature of fluid inclusion is 187℃,the salinity is 5.03wt%NaCl,the density is 0.919g/cm3,the pressure is 46.00MPa,and the ore-forming depth is 5.37km;in Jinzhuyuan deposit,the average homogenization temperature of fluid inclusion is 178℃,the salinity is 5.54wt%NaCl,the density is 0.913g/cm3,the pressure is 48.42MPa,and the ore-forming depth is 5.51km.On the whole,the fluid inclusions belong to the system of medium-low temperature,low salinity and medium density.And it can be concluded that this ore deposit was formed in a mesogenetic ore-forming environment.