302铀矿床矿石中铀的存在形式及矿物组合特征

摘要

Electronic probe analysis indicated that uranium in uranium deposit No.302 mainly existed as independent uranium minerals and minors occurred as isomorphism of thorium in zircon and rutile and other accessory minerals.The independent uranium ore minearal mainly as pitchblende,some as coffinG ite,uranothorite, brannerite and the second uranium minerals of uranophane, autunite, chalcolite. The ore consist of five kind mineral combination,the diversity of uranium ore mineral combination reG flects the long term and complex activity of hydrothermal fluid in the deposit,which also indicate the multiphases and variety of fluid composition and forming environment in hydrothermal activity. Alteration related with uranium mineralization are siliconization,hematization,purple black fluoritizaG tion,pyritization,calcitization,sericitization and chloritization,etc.%电子探针分析显示,302铀矿床矿石中铀的存在形式以独立铀矿物为主,少量呈类质同像赋存于钍石、锆石及金红石等副矿物之中。独立铀矿物以沥青铀矿为主,其次有铀石、铀钍石、钛铀矿等原生铀矿物和硅钙铀矿、钙铀云母、铜铀云母等次生铀矿物。铀矿石具有5种不同的矿物组合,这种矿物组合的多样性,反映了该矿床热液流体活动的长期性和复杂性,即成矿热液流体作用具有多阶段性,以及热液流体组成和成矿环境的多变性。与铀矿化相关的蚀变有硅化、赤铁矿化、紫黑色萤石化、黄铁矿化、方解石化、绢云母化及绿泥石化等。