乌克兰第聂伯盆地砂岩型铀矿床矿化特征与成矿机理  

Mineralization characteristics and metallogenetic mechanism of sandstone-type uranium deposits in Dnieper Basin, Ukraine

作　　者：倪仕琪 蔡煜琦[1] 宋继叶[1] NI Shiqi;CAI Yuqi;SONG Jiye(CNNC Key Laboratory of Uranium Resource Exploration and Evaluation Technology,Beijing Research Institute of Uranium Geology,Beijing 100029,China)

机构地区：[1]核工业北京地质研究院,中核集团铀资源勘查与评价技术重点实验室,北京100029

出　　处：《世界核地质科学》2018年第4期210-216,共7页World Nuclear Geoscience

基　　金：国家重点研发计划“乌克兰中部基洛沃格勒深部铀资源勘探关键技术与装备合作研究”(编号:2016YFE0206300)资助

摘　　要：第聂伯(Dnieper)盆地位于乌克兰(Ukraine)地盾内,砂岩型铀矿床分布在盆地中东部的第聂伯—布格(Dnieper-Bug)铀矿区。综合资料表明,矿床主要类型是古河谷砂岩型。矿床均产于前寒武纪花岗岩基底之上或边缘,含矿层是始新统Buchak组砂岩,含矿砂岩以河流相为主并受古河道控制,具有切入基底的底部古河道沉积特征,含水性好,渗透率较高,利于流体在岩层中运移。铀成矿作用以沿古河道斜面运动的层间氧化为特征,底顶板分别是结晶基底和泥质隔水层。铀矿体呈板状、透镜状和卷状,大致位于氧化带尖灭处。铀矿物分布与植物碎屑和黏土矿物有关。Dnieper Basin is located in the Ukrainian Shield and sandstone-type uranium deposits have been delineated in the Dniper-Bug metallogenetic region.The interpretation of regional geological survey suggests that these deposits occur in paleochannels of the paleo-valley,which are located above and on the edge of the Precambrian granite basement.Mineralized sandstone is mainly the sandstone in Eocene Buchak Formation.The sandstone also has the characteristics of basal channels sediments which incised the underlying basement and are suitable for the migration of mineralizing fluids due to good permeability.Ore-bearing horizons are sandwiched between basement rocks and mudstone.Ore bodies are of peneconcordant tabular,lenticular,roll configuration and they are controlled by zones of ground-bed or infiltration oxidation.The distribution of uranium mineral is related with the carbonized plant fragment and clays.

关 键 词：砂岩型铀矿 古河谷 成矿机理 第聂伯盆地 乌克兰 

分 类 号：P619.14[天文地球—矿床学] P612[天文地球—地质学]