云南南秧田与福建丁家山白钨矿成分特征对比研究

Component characteristics of scheelite in Nanyangtian,Yunnan Province and Dingjiashan,Fujian Province

通过云南麻栗坡南秧田矿段和福建尤溪丁家山矿区两地白钨矿的成分特征对比研究,寻找异同点并反演形成环境。利用电子探针对两地的白钨矿进行原位分析,发现南秧田矿段中的白钨矿基本不含Mo,而丁家山矿区的白钨矿普遍含Mo,Mo均以类质同象形式置换W,并在丁家山矿区发现由Mo含量变化引起的白钨矿规则成分环带。分析认为,南秧田白钨矿是在中高温氧化条件下形成,且成矿流体中Mo含量很低。而在丁家山矿区发现白钨矿环带结构,表明丁家山白钨矿的形成经历了温度逐渐降低、氧化环境变为还原环境、成矿流体中Mo含量从低到高的变化。

In order to find similarities and differences and infer forming environment, we compare component characteristics of scheelite between Nanyangtian ore block, Malipo, Yunnan province and Dingjiashan mining area, Youxi, Fujian province. By using electron probe in si- tu analysis of scheelite between the two places, it is found that scheelite basically doesn＇t contain molybdenum in Nanyangtian ore block, while scheelite commonly contains molybde num in Dingjiashan mining area. Molybdenum substitute tungsten in the form of isomor phism and it is found that the change of molybdenum content causes the regular composition al zoning of scheelite of Dingjiashan. The analysis result indicates that the forming condition of Nanyangtian scheelite is medium-high temperature, oxidation, and molybdenum content which is very low in the ore-forming fluid. The zonal structure of scheelite shows that Dingjiashan scheelite experience temperature decreases gradually, oxidation turns into reduc tion environment, molybdenum content changes from low to high in the ore-forming fluid.