广西水汶盆地大山铀矿床地质特征及铀的矿物学分析

Geological Characteristics and Mineralogical Analysis State of Dashan Uranium Deposit in Shuiwen Basin,Guangxi

为查明水汶盆地大山铀矿床成矿地质特征及铀的赋存状态,在野外地质调查基础上,利用岩矿鉴定、扫描电镜及电子探针分析等手段开展研究。结果表明:矿床赋存地层为西垌组三段火山碎屑岩,铀矿化严格受构造控制,主要赋存于近南北向断裂构造中,呈脉状、透镜状,均为隐伏矿体;铀矿石具角砾状、星散浸染状构造,铀矿物主要以微粒沥青铀矿、铀石等独立矿物形式存在,多以粒状、斑团状分布在不同矿物颗粒的间隙、填隙部位或沿着黄铁矿的裂隙、溶蚀凹坑充填,另有少量星点状、粒状铀矿物被黄铁矿、石英矿物包裹。该研究可为未来矿山开采选冶工艺确定提供数据指导。

In order to find out the metallogenic geological characteristics and occurrence state of urani-um in Dashan uranium deposit in Shuiwen Basin,rock and mineral identification,scanning electron micros-copy and electron probe analysis are carried out on the basis of field geological investigation.The results show that the deposit occurs in the pyroclastic rock of the third member of Xidong Formation,and uranium mineralization is strictly controlled by structure,mainly occurring in the near north-south fault structure,in vein and lens shape,and all of them are hidden ore bodies.Uranium ore has brecciform and scattered dis-seminated structure,and uranium minerals mainly exist in the form of independent minerals such as fine pitchblende and uranite,which are mostly distributed in granular and porphyritic forms in the gaps and in-terstitial positions of different mineral particles or along the cracks and dissolution pits of pyrite,and a small amount of stellate and granular uranium minerals are coated by pyrite and quartz minerals.The research can provide data guidance for the determination of mining and smelting process in the future.