三矿沟铜-铁-钼多金属矿床是大兴安岭地区三矿沟-多宝山构造-成矿带中一个比较典型的矽卡岩型矿床.对干矽卡岩阶段(I)的石榴子石、湿矽卡岩-氧化物阶段(Ⅱ)的石英、早期硫化物阶段(Ⅲ)的石英和晚期硫化物阶段(Ⅳ)的方解石中的流体包裹体进行了岩相学观察和显微测温研究.研究结果表明,成矿各阶段热液矿物中的原生流体包裹体类型丰富,主要为气液两相包裹体,其次为纯气相包裹体,偶见纯液相包裹体.石英中也有大量舍NaCl子矿物的多相包裹体,其均一温度变化于152～478C之间,盐度为1.57～58.02wt％ NaC1,密度变化范围为0.64～1.18g/cm3,总体属中一高温度、中一高盐度、中等密度的体系；据此计算的成矿压力范围为39.44～133.65MPa,成矿深度介于3.94～9.64km之间,表明该矿床形成于中深成环境.%Located in the Sankuanggou-Duobaoshan tectonic-metallogenic belt of Da Hinggan Mountains, the Sankuanggou Cu- Fe-Mo polymetallic deposit is a typical skarn deposit. Petrographic observation and microthermometric study were carried out for fluid inclusions from garnet at the anhydrous skarn stage ( I ), quartz at the hydrous skarn-oxide stage (II), quartz at the early sulfide stage (III) and calcite at the early late sulfide stage (IV). Petrographic observations reveal that various types of fluid inclusions are present in hydrothermal minerals of different ore-forming stages, comprising mainly vapor-liquid two-phase inclusions, subordinately vapor inclusions, and occasionally liquid inclusions as well as NaCl daughter mineral-bearing multiphase inclusions in quartz. Studies show that their homogenization temperatures vary from 152℃; to 478t, their salinities are 1.57~58.02 wt% NaCl, and their densities range from 0.64 g/cm3 to 1.18 g/cm3, thus belonging to the ore-forming system of medium-high temperature, medium-high salinity and medium density. In addition, mineralization pressures were calculated on the basis of homogenization temperatures and salinities, and the results show that the mineralization pressures vary from 39.44 Mpa to 133.65 Mpa, whereas the ore-forming depths are in the range of 3.94 km to 9.64 km, indicating that this ore deposit was formed in a mesogene ore-forming environment.
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