西北地质2026，Vol.59Issue(3)：264-278,15.DOI:10.12401/j.nwg.2025040
海拉尔盆地克鲁伦凹陷伊敏组铀矿物赋存特征及铀成矿条件分析
Analysis on the Occurrence Characteristics of Uranium Minerals and Mineralization Conditions in the Yimin Formation of Kelulun Depression,Hailar Basin
摘要
Abstract
The sandstone-type uranium deposit in the Kelulun Depression is the first industrial uranium deposit discovered in the Hailar Basin.In order to preliminarily identify the types,occurrence characteristics,and miner-alization significance of uranium minerals in the study area,this paper conducts a systematic study of the ore-bearing sandstone in the target layer by using polarized light microscopy combined with electron probe analysis on the basis of a field investigation.The results show that uranium mineralization in the study area occurs at the front edge of the braided river delta of the Yimin Formation.The rock type of the ore-bearing target layer is mainly medium-fine-grained feldspathic litharenite,with the overall development post-generation alteration.Uranium minerals are mainly coffinite,followed by uranium-titanium oxide.Coffinite is mainly distributed in colloidal or stellate forms in or around pyrite,and a few are filled in the edges of debris particles or dissolution pits in irregular granular form.Uranium-titanium oxides are mostly distributed in irregular granular forms in the biotite cleavage cracks.The coffinite and uranium-titanium oxide,as the first discovered independent uranium minerals in the study area,fill the gap left by the absence of uranium minerals in the Hailar Basin.In terms of uranium mineralization conditions,the Permian granite and intermediate-acidic volcanic rocks in the west of the study area provide sufficient uranium sources for the sandstone-type uranium mineralization in the area.Under the action of reducing media such as oil and gas,organic carbon,and sulfides in the area,U6+in the ore-forming fluid is reduced to U4+and precipitated into mineralization in the form of coffinite and uranium-titanium oxide.关键词
砂岩型铀矿/铀石/铀钛氧化物/伊敏组/克鲁伦凹陷Key words
sandstone-type uranium deposit/coffinite/U-Ti oxide/Yimin Formation/Kelulun Depression分类
天文与地球科学引用本文复制引用
孟繁敏,聂逢君,夏菲,严兆彬,孙达,周文博,张荣,王长虹..海拉尔盆地克鲁伦凹陷伊敏组铀矿物赋存特征及铀成矿条件分析[J].西北地质,2026,59(3):264-278,15.基金项目
国家自然科学基金联合基金项目(U2244205、U2067202),核技术研发科研项目(202411GFKGJHJSYF01)联合资助. （U2244205、U2067202）
