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比利亚谷矿床是内蒙古额尔古纳成矿带内新发现的一个铅锌(银)矿床,具有大型矿床的成矿潜力。主矿体呈脉状产于上侏罗统塔木兰沟组和满克头鄂博组火山岩地层中,受NW,NWW向张性断裂构造控制;主要金属矿物有方铅矿、闪锌矿、黄铁矿、黄铜矿、辉银矿等。为确定该矿床的成矿流体特征及成因类型,对矿石中的石英、重晶石和闪锌矿开展了流体包裹体的岩相学观察、显微测温和激光拉曼光谱分析。结果表明,上述矿物中主要发育富液相、CO2三相和少量含子矿物三相包裹体;富液相包裹体的均一温度与盐度分别为102℃~378℃和0.2%~10.5%NaCl eqv,CO2三相包裹体的均一温度和盐度分别为124℃~256℃和1.8~11.2%NaCl eqv,含子矿物三相包裹体的均一温度与盐度分别为220℃和42.4%NaCl eqv。单个流体包裹体气相成分的激光拉曼光谱分析显示,除石英中的部分富液相包裹体的气体成分含CO2外,不同矿物中的富液相包裹体的气体成分均为H2O。此外,该矿床成矿流体的盐度范围波动较大,重晶石中包裹体的均一温度分布范围较广,因此成矿流体属不均匀流体,流体混合作用是该矿床的重要成矿机制。综合认为,比利亚谷铅锌(银)矿床应属赋存于中生代火山岩中的与浅成-超浅成岩浆作用有关的中低温热液脉型矿床。
The Villavalue deposit is a newly discovered lead-zinc (silver) deposit within the Erguna metallogenic belt in Inner Mongolia and has potential for metallogenesis of large deposits. The main ore body is vein-shaped in the Upper Jurassic Damulangou Formation and Manke Obo Group volcanic rock strata, controlled by the NW and NWW trending tensional faults. The major metalloids include galena, sphalerite, yellow Iron ore, chalcopyrite, such as silver mine. In order to determine the characteristics and genetic type of ore-forming fluid in this deposit, petrographic observation, microscopic temperature measurement and laser Raman spectroscopy analysis of fluid inclusions were carried out on quartz, barite and sphalerite in ore. The results show that the above minerals mainly consist of three-phase inclusions with rich liquid phase, three-phase CO2 and small amount of ore-bearing minerals. The homogeneous temperature and salinity of liquid-rich inclusions are 102 ℃ ~ 378 ℃ and 0.2% ~ 10.5% NaCl The homogenization temperature and salinity of eqv and CO2 three-phase inclusions are 124 ℃ ~ 256 ℃ and 1.8 ~ 11.2% NaCl eqv, respectively. The homogenization temperatures and salinities of three-phase inclusions in sub-minerals are 220 ℃ and 42.4% NaCl eqv . The laser Raman spectroscopy analysis of the gas components of a single fluid inclusion shows that the gas components of the fluid-rich inclusions in different minerals are H2O except for the gas components of some of the liquid-rich inclusions in quartz. In addition, the range of salinities of ore-forming fluids in this deposit fluctuates widely, and the homogenization temperature distribution of inclusions in barite is wide. Therefore, the ore-forming fluid is an inhomogeneous fluid, and fluid mixing is an important metallogenic mechanism of this deposit. Taken together, the Biloya Valley Pb-Zn deposit should belong to the Meso-Low-temperature hydrothermal vein-type deposits associated with shallow-ultra-magmatic magmatism in Mesozoic volcanic rocks.