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在湖南一个中、新生代断陷盆地内的某大型铀矿床,属于沉积成岩型。对手含矿层中矿质的沉积环境,前人主要认为属河流相,笔者认为是湖泊相中的水下冲积平原亚相。提出这种看法的根据,是分析了地层剖面,对含矿层的某些化学成分、矿物成分、层理类型等进行了分析,指出该的矿床含矿层中的胡相标志相当明显,而在湖相的基础上,又有许多同生角砾、冲刷坑、卷曲层、递变层理等,这些现象的发育是永下河道冲刷及重力密度浊流的结果。另一方面,当时构造运动较剧烈、地形反差较大、气候比较燥热,铀无法在氧化性较强的河流相中失面积沉淀,只能在还原性较强的湖相中沉积。而水下河道冲刷、重力密度浊流也有助于铀在潮底同生富集。
In Hunan, a large-scale uranium deposit in the Cenozoic and Cenozoic fault basins belongs to sedimentary diagenesis. Ore-bearing mineral deposits in the ore-bearing environment, the predecessors mainly believe that the river facies, I believe that the lacustrine facies subaqueous alluvial plain subfacies. This view is based on the analysis of stratigraphic profiles and analysis of some chemical compositions, mineralogical compositions, and bedding types of the ore-bearing strata, pointing out that the beige flag in the ore-bearing strata of the deposit is quite obvious, On the basis of the facies, there are many identical breccias, scouring pits, curly layers and graded bedding. The development of these phenomena is the result of eroded river channels and gravity-density turbidity currents. On the other hand, at that time, the tectonic movement was rather violent, the terrain contrast was rather large, the climate was hot and dry, and uranium could not lose its sediment in the highly oxidized river facies and could only be deposited in the highly reducible lake facies. The underwater channel erosion, gravity density turbidity flow also helps uranium enrichment in the tide with students.