湘西沃溪钨锑金矿床地质地球化学特征

沃溪钨锑金矿床产于元古界板溪群马底驿组中、上段紫红色绢云母板岩中,受层间断裂带控制。矿体具斜列延伸、多层产出、近似等间距分布特点,见有层间石英脉、网状石英脉和节理裂隙脉三类矿体。金矿物以次显微、显微金为生,主要赋存于以黄铁矿、辉锑矿为主的硫化物中,As、Sb是其标型元素。成矿物质与赋矿地层密切相关,成矿流体是非岩浆源的,成矿作用是在中低温度、偏低盐度、中性略偏酸性的变质热液中发生的,构造运动对成矿过程起着控制作用。矿床属于火山沉积—变质热液成因。

GEOLOGIC AND GEOCHEMICAL FEATURES OF WOXI W-Sb-Au ORE DEPOSIT IN WESTERN HUNAN

Woxi W-Sb-Au ore deposit occurs in the sericite slate, purplish red in color, located in the medium and upper members of Madiyi Formation of Proterozoic Banxi Group. contro11ed by the interlayer fracture zones. The orebodies occur as echelon-like veins, in many layers, and are equal in distance. Three kinds of orebody are found: interbeded quartz vein, network quartz vein and joint fracture quartz vein. Gold minerals are dominated by submicro and micro-gold, existing mainly in sulfide minerals such as pyrite and stibnite, in which As and Sb are typomorphic elements. The ore-forming material is closely related to the ore-hosting strata; the ore-forming fluid is derived from non-magmatic sources; the mineralization took place in the metamorphic fluid of medium to low temperature, relatively low saltiness and neutral by acid media condition. Tectonic movements controlled the ore-forming process. The deposit belongs to volcanic sedimentary metamorphic hydrothermal origin.