单个流体包裹体成分研究对湘西沃溪矿床成矿流体演化及金锑钨沉淀机制的指示

Despite the widely recognized Au-Sb-W association in quartz vein type deposits, the characteristics and mechanisms of paragenesis and separation of Au, Sb and W are unclear. Detailed chemical composition of different mineralization period can be obtained by LA-ICP-MS analysis of individual fluid inclusions, tracing the origin and evolution of ore-forming fluid. The Woxi deposit, with a unique elemental association of Au-Sb-W, has been chosen as an ideal target for studying the mechanism of paragenesis and separation of Au, Sb and W in this proposal. Based on detailed geological and lab study, ore minerals and quartz, from early veins to later veins in the Woxi deposit, are selected for LA-ICP-MS analyses of individual fluid inclusions systematically. This study will contribute to (1) understanding the characteristics, origin, evolution and precipitation mechanisms of the ore-forming fluid. (2) revealing constrains on paragenesis and separation of Au, Sb and W, and then improving the ore-forming theory, serving similar ore deposit exploration.

石英脉型矿床中Au-Sb-W元素组合较为常见，但有关这三种元素共生分异特征及形成机制的认识尚不清楚。单个流体包裹体成分能够很好地反映不同成矿期次/阶段流体的化学组成，示踪流体来源及演化过程等，对深刻认识元素共生分异机制具有重要意义。本项目拟选取国内外绝无仅有的钨锑金共生的大型金矿——沃溪矿床为研究对象，在详细的野外调查及室内研究的基础上，系统地对各阶段石英脉中的矿石矿物和石英开展单个流体包裹体LA-ICP-MS成分及相关研究。开展该项研究有以下意义：（1）为重新认识该矿成矿流体的性质、来源、演化以及矿石沉淀机制提供了理论依据。（2）有助于进一步查明该矿金、锑、钨在热液成矿过程中的共生分异机制，丰富成矿理论及服务区域同类矿床的勘探。