中国斑岩铜（钼）矿床中辉钼矿Re含量变化及控制因素

铼作为战略性关键金属之一,越来越受到人们的关注.Re主要以类质同象的形式赋存在辉钼矿中,然而,不同成因、不同类型矿床的辉钼矿中Re含量差异较大.在钨、锡矿床中Re含量较低,在斑岩型铜(钼)矿床中Re含量较高,后者是全球Re资源的主要载体.前人对于辉钼矿中Re元素的研究主要基于Re-Os同位素年代学,而对于不同区域、不同时代、不同类型斑岩型铜矿床中辉钼矿Re含量的变化规律及其控制因素的研究较少.文章通过汇总前人发表的斑岩型铜(钼)矿床的Re-Os同位素数据,从含矿斑岩的Sr、Nd、Hf等数据与辉钼矿中平均Re含量的关系等角度,探讨了其变化规律及控制因素.结果表明:中国斑岩型铜(钼)中Re含量随着成矿物质从地幔到地壳,依次减少;成矿流体的氧逸度、辉钼矿的产状、与其伴生的硫化物种类及不同的成矿阶段等因素共同控制了辉钼矿中Re的含量.

Variations and controlling factors of Re content of molybdenite in porphyry Cu (Mo) deposits of China

Re (rhenium), as one of the key strategic metals, has attracted more and more attention among researchers. Re occurs mainly in molybdenite in the form of isomorph. However, Re content in molybdenite varies with different geneses and types of deposits. Re content in tungsten and tin deposits is relatively low, while that in porphyry copper (molybdenum) deposits is relatively high, which serve as the main carrier of Re resources in the world. Previous studies of Re in molybdenite have been mainly based on Re-Os isotope chronology, but the studies of the variation rules and controlling factors of Re content in molybdenite of porphyry copper deposits in different regions, ages and types have been very insufficient. In this study, by collecting the available Re-Os isotope data of porphyry copper (copper-molybdenum) deposits, the relationship between Sr-Nd-Hf of ore-bearing rocks and the average Re content in molybdenite was investigated. The results show that the Re content in porphyry copper (copper-molybdenum) deposits in China decreases with the change of metallogenic material from the mantle to the crust. Re content in molybdenite is controlled by oxygen fugacity of ore-forming fluid, the modes of occurrence of molybdenite, the types of sulfides associated with molybdenite, different metallogenic stages and other factors.