初论稀有金属矿床研究的一些重要进展

稀有金属矿是重要的战略性储备资源,其成矿机制和成矿作用研究也一直受到了国际上的广泛关注。本文从矿床类型特征、岩浆岩、碳酸岩体与稀有金属矿化的关系、矿床成矿流体与成矿机制和成矿年代学等4个方面,对近年来的研究进展进行了简要的论述。稀有金属矿床以花岗岩型和花岗伟晶岩型为主,与稀有金属矿化有关的岩体的地球化学组成可以有效指示稀有金属矿化趋势,锆石常具有特殊的化学组成特征(高Th/U比值(1~10)、Y/Ho20、Sm/Nd0.5、Nb/Y0.08和Hf2wt%)。流体不混溶作用在稀有金属矿床,尤其是伟晶岩型矿床的成矿流体中常见,成矿多经历了从岩浆-热液多个阶段,流体成分较复杂,除B、F等外,最近还发现了较少见的碳酸盐矿物,其成矿机制值得深入研究。

A preliminary discussion on some important advances of the rare metal deposit

Rare metal ore reserves are important strategic resources, on which metallogenic mechanisms and mineralization studies have received widespread attention in the world. This article presents a brief review that focuses on four aspects of recent progress on this issue, i.e. the characteristics of the deposit type, relationships between magmatic rocks, carbonate rocks and rare metals mineralization, metallogenic fluids and mineralization mechanism, and metallogenic chronology. Rare-metal deposits are dominated by granite type and granitic pegmatite type, with the geochemical composition of the rare metal mineralization-related rocks which can effectively indicate the metals mineralization trend. Usually zircon has special chemical composition characteristics, such as high Th/U ratio (1~10), Y/Ho<20, Sm/Nd>0.5, Nb/Y>0.08, and Hf>2wt%. Fluid immiscibility is commonly present in the rare metal deposits, especially in mineralization fluids of the granitic pegmatite-type deposits, and the mineralization experienced multiple phases from magma to hydrothermal phases. Fluid composition is more complex, on which in addition to B and F elements, rare carbonate minerals have been discovered recently, and their metallogenic mechanisms need further study.