中文摘要：

铀是变价元素,氧化还原条件控制铀的迁移和沉淀。铀在氧化环境中呈U~（6＋）形式存在,在还原条件下则以U~（4＋）形式存在。氧化态六价铀主要以可溶的碳酸铀酰/氟化铀酰络合物形式在水溶液中迁移,还原态四价铀主要以沥青铀矿和铀石等形式富集沉淀成矿。热液铀矿的形成需要一对空间上密切共生的氧化障/氧化剂和还原障/还原剂,二者缺一不可。首先,氧化障中氧化剂将富铀岩石中的铀大量氧化形成U~（6＋）,溶解进入水溶液迁移;第二,高氧化性富铀溶液遇到还原障,U~（6＋）还原成U~（4＋）沉淀下来,富集形成铀矿。前人虽然对铀的地球化学性质及氧化还原反应在铀成矿中作用已比较了解,但如何在实际铀矿成矿系统中准确识别氧化还原障,有效利用氧化还原障的控矿机理指导找矿,还存在一些模糊认识,制约了铀成矿理论的发展和找矿方法的提升。本文以我国最重要的砂岩型铀矿、火山岩型铀矿、花岗岩型铀矿和变质型铀矿为例,总结了与铀矿化有关的氧化还原障的主要类型,探讨了红层等蒸发盐地层（氧化障）,有机质、煌斑岩等中基性岩脉（还原障）与铀矿之间的关系及控矿机制,揭示了成矿盆地中铀-煤、铀-气（油）共生的机制,阐明了翁泉沟硼、铁、铀矿共生原因,建立了不同类型铀矿成矿模型。

英文摘要：

Uranium is a volatile element, and the redox conditions control the migration and precipitation of uranium. In the oxidation environment, uranium is in the form of U6＋ , and in the form of U4＋ in reduction condition. The oxidation state of six valence uranium is mainly in soluble uranyl carbonate / uranyl fluoride complexes form, in aqueous solution migration, and the reductive tetravalent uranium is mainly enriched and precipitated in the form of pitchblende and coffinite in the ore-forming. The formation of hydrothermal uranium requires an oxidation harrier, but also a reduction barrier, and the two are indispensable. First of all, the oxidation agent / oxidation barrier will form a large amount of uranium in uranium rich rock to form U6＋ , and dissolved into the water solution; Second, the highly oxidized uranium rich solution is reduced to U~＋ , when they met the reduction barrier, and U6＋ is reduced to precipitation, which is enriched in uranium deposit. Although the previous researches have been made on the geochemical characteristics and redox reactions of uranium in uranium mineralization, it is found that there are still some fuzzy understanding, restricting the development of uranium metallogenic theory and the improvement of ore prospecting method. In this paper, the most important sandstone type, volcanic rocks type, granite type uranium deposits have been taken as the examples to been discussed, we summarize the main types of uranium mineralization related to the oxidation and reduction barriers, discussed the relationship between uranium and the red layer evaporite strata （oxidation barrier） and lamprophyre in mafic dykes （reducing barrier）, and control mechanisms of ore, reveals the mechanism of symbiotic metallogenic basin uranium-coal, uranium-gas （oil）, clarify the Weng Quangou boron, iron, uranium symbiotic genesis, and established different types of uranium mineralization models.