关键金属铍的成矿机制与找矿前景

Metallogenic mechanism and prospect of key metal beryllium

铍是战略性新兴产业和国防军工行业不可替代的一种关键金属,其赋存形式、成矿机制以及资源分布是关键金属矿产研究的重要内容。地球化学性质上,铍在大部分造岩矿物晶体结构中表现为不相容,倾向在岩浆演化晚期甚至热液阶段富集结晶。然而,铍又是一种典型的双性元素,在酸性和碱性环境中均可得到富集沉淀,因而铍矿主要赋存于花岗质岩石和碱性岩及其相关岩石中,与岩浆-热液过程相关的铍矿床主要包括“火山岩型”铍矿、高分异花岗岩-伟晶岩型铍矿、云英岩-石英岩型铍矿、碱性岩型铍矿、矽卡岩型铍矿、碳酸岩型铍矿等铍矿床。酸性和碱性岩浆的结晶分异、岩浆-热液过程以及挥发组分含量等制约Be的富集、迁移、结晶与成矿过程。同时,铍常与其它稀有稀土金属元素协同成矿,形成共/伴生矿床,在矿产开采过程中,应注意分选工艺、提纯过程等研究。我国铍资源有望在花岗岩型、伟晶岩型以及“火山岩型”铍矿获得突破,东南沿海火山岩地区、大兴安岭火山岩地区、藏南地区、新疆中西部地区等区域可成为铍资源的重要靶区。

Beryllium(Be)is one of the unsubstitutable key metals in strategic emerging industries and national defense industries,where its occurrence,metallogenic mechanisim and resource distribution are most important contents in the research of key metal minerals.Beryllium is one of incompatible elements,which can t enter into most rock-forming minerals,and tends to be enriched and crystallized during the late magmatic stages or even hydrothermal stages.However,beryllium is a typical amphoteric element,and can be enriched and precipitated in both acidic and alkaline environments.Most granitic rocks,alkaline rocks and their related rocks are thus the main carriers of beryllium ore.Be deposits related to magmatic-hydrothermal process mainly include“volcanogenic type”Be ore,highly differentiated granite-pegmatite type Be ore,greisen quartzite type Be ore,alkaline rock type Be ore,skarn type Be ore,and carbonatite type Be ore,and so on.The concentration,migration,crystallization and mineralization of beryllium are absolutely controlled by the differentiation of acidic and alkaline magma,magmatic-hydrothermal processes and volatile component content.Together with other rare earth metal elements,moreover,beryllium is often mineralized to form symbiotic deposits and associated deposits.In the exploitation processes,we should pay attention to improve the metallurgical processes such as separation process and purification process.It is expected to make a breakthrough in granite type,pegmatite type and“volcanogenic type”Be ores in our country.The southeast coastal volcanic rock area,Greater Khingan volcanic rock area,southern Tibet and central-western Xinjiang can become important target areas of Be resources.