内蒙古老道沟铜多金属矿床地质特征及流体包裹体研究

老道沟铜多金属矿床产于燕山早期闪长岩侵入体之中,为受断裂控制的蚀变破碎带-石英脉复合型矿床。矿区成矿早期以铜矿化为主,晚阶段以铅、锌和银成矿为主。流体包裹体研究结果表明,成矿早、晚阶段石英中均主要发育气-液两相流体包裹体,包裹体均一温度变化范围分别为226.9℃～298.5℃及179.3℃～265.4℃,盐度分别为5.26%～9.47%NaCl和2.57%～6.30%NaCl,表明成矿流体总体属中-低温、较低盐度热液体系,主要来源于岩浆热液及大气降水。根据矿化特征及流体包裹体研究结果综合分析认为该矿床属中-低温热液成因类型。

Geological characteristics and fluid inclusion study of Laodaogou copperpolymetallic deposit in Inner Mongolia

Laodaogou copperpolymetallic deposit is a faultcontrolled altered brecciation belt quartz vein type deposit that occurred in granodiorite body of early Yanshanian period.The early stage of mineralization is copperdominated and leadzincsilver dominated at the later stage of mineralization in the mining district. Fluid inclusion study showed that mainly aqueous two-phase fluid inclusions developed in quartz both from the early and later stages of mineralization .The homogenization temperature of aqueous two-phase fluid inclusions in quartz of the early mineralization stage ranges from 226.9% to 298.5℃,and salinity ranges from 5.26 wt%NaCI to 9.47wt%NaCI;and the homogenization temperature and salinity of fluid inclusions in quartz from the later stage of mineralization varies between 179.3℃to265.4℃ and 2.57 wt%NaCI to 6.30wt%NaCI respectively. So the mineralization solutions is generally of mediumlow temperature and relatively low salinity type and mainly came from magmatic activities and meteoric waters. Coprehensive analyses results in the conclusion that Laodaogou cepperpolymetallic deposit is of mesothermal type in origin.