二连盆地哈达图铀矿床特富矿体成因:来自微量元素和稀土元素地球化学的证据  

Genesis of Extremely Rich Ore Body in the Hadatu Uranium Deposit,Erlian Basin:Evidence from Trace and Rare Earth Element Geochemistry

作　　者：李红梅 李伟涛 吴德海 潘家永[1,4] LI Hong-mei;LI Wei-tao;WU De-hai;PAN Jia-yong(School of Earth Sciences,East China University of Technology,Nanchang 330013 China;Beijing Research Institute of Uranium Geology,Beijing 100029,China;School of Resources,Environment and Jewelry,Jiangxi College of Applied Technology,Ganzhou 341000,China;State Key Laboratory of Nuclear Resources and Environment,East China University of Technology,Nanchang 330013,China)

机构地区：[1]东华理工大学地球科学学院,江西南昌330013 [2]核工业北京地质研究院,北京100029 [3]江西应用技术职业学院资源环境与珠宝学院,江西赣州341000 [4]东华理工大学核资源与环境国家重点实验室,江西南昌330013

出　　处：《稀土》2021年第4期71-83,共13页Chinese Rare Earths

基　　金：中核集团研发项目(地LCEQ01,地LCEQ03);核资源与环境国家重点实验室开放基金项目(2020NRE03)。

摘　　要：哈达图矿床是近年来新发现的大型砂岩型铀矿床,成矿潜力优越。在矿物学的基础上,对哈达图铀矿床特富矿石(>3000μg/g)进行了微量元素、稀土元素地球化学特征研究,通过元素的地球化学行为,揭示特富矿体的成因机制。结果表明,哈达图矿床富矿石主要以沥青铀矿为主,周围发育了大量黄铁矿和有机质;微量元素地球化学特征表明,特富矿石中明显富集了Co、Ni、Zn等元素,推测有深部还原性流体活动参与,含矿段自氧化带至富矿体氧化还原敏感元素(Mo、RE、U)逐渐富集,指示了层间氧化作用的发生;稀土元素配分曲线表现出既相似又相分离的特征,暗示富矿体后期经历了热液流体改造,使铀再次富集。Hadatu deposit is a large sandstone type uranium deposit newly discovered in recent years with superior metallogenic potential. In this paper, on the basis of mineralogical investigation, the geochemical characteristics of trace elements and rare earth elements of the extra-rich ore(> 3000 μg/g) in the Hadatu uranium deposit are studied. Through the geochemical behavior of elements, the genetic mechanism of the extra-rich ore body is revealed. The results show that the rich ore in Hadatu deposit is mainly comprised of pitchblende, surrounded by a lot of pyrite and organic matter. The geochemical characteristics of trace elements show that Co, Ni, Zn and other elements are obviously enriched in the ultra-rich ore, and the deep reductive fluid activity is presumed to be involved. The ore-bearing zone extends from the oxidized zone to the rich ore body, and the redex sensitive elements(Mo, RE, U) are enriched gradually, indicating the occurrence of interlayer oxidation. The rare earth partition curves in different oxidation stages have similar distribution patterns with differential fractionation to some degree, suggesting that the ore-rich body underwent hydrothermal fluid modification in the late stage to enrich uranium again.

关 键 词：二连盆地 铀矿床 特富矿体 微量元素 稀土元素 地球化学 

分 类 号：P595[天文地球—地球化学]