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嵩溪银（锑）矿是一个新发现的大型独立银矿。矿物流体包裹体超高真空四极气相质谱系统测定显 示，该矿成矿流体中存在多种轻烃有机气体，主要由Ｃ１－Ｃ４饱和烷烃组成，仅含微量Ｃ２－Ｃ４不饱和烯烃和芳烃，说明 成矿过程基本未受到高温岩浆作用的影响。化学平衡研究表明，这些轻烃气体为微生物成因和沉积岩围岩中Ⅱ类 干酪根热解成因的混合气体，其中前者占２／３以上，说明成矿中微生物活动曾起到相当大的作用；后者的平衡温度 为３００℃，远超过成矿深度所能达到的地热温度，因此这部分轻烃气体可能源于沉积盆地深处，经成矿流体长距离携 带到达较浅的矿化部位。文章从一个侧面证实嵩溪矿可能为沉积热卤水改造型矿床，而不是前人所认为的海底基 性火山喷流或中低温火山热液充填矿床。
Songxi silver (antimony) mine is a newly discovered large-scale independent silver. The determination of mineral fluid inclusions by ultra-high vacuum gas chromatography-quadrupole mass spectrometry system shows that there are many light hydrocarbon organic gases in the ore-forming fluid, which are mainly composed of C1-C4 saturated alkanes, containing only a small amount of C2-C4 unsaturated olefins and aromatics, Indicating that the metallogenic process is basically unaffected by the high temperature magmatic activity. Chemical equilibrium studies have shown that these light hydrocarbon gases are microbial gases and gas mixtures of type II kerogen in the sedimentary rocks, of which the former account for more than two-thirds of the total. This indicates that microbial activities played a significant role in mineralization. The equilibrium temperature of the latter is 300 ℃, far exceeding the geothermal temperature that can be achieved by metallogenic depth. Therefore, this part of light hydrocarbon gas may originate from the deep sedimentary basin and reach the shallower mineralization site through long-distance ore-forming fluid. From one aspect, the article proves that Songxi Mine may be a deposit of altered hydrothermal brine, rather than the previous thought of submarine basal volcanic jet or medium- and low-temperature volcanic hydrothermal mineralization deposits.