钱家店铀矿床红色泥砾砂岩岩石学特征及矿化成因分析

钱家店凹陷中的含矿层位主要为上白垩统姚家组,在实际勘探过程中经常见姚家组发育的红色泥砾砂岩中存在铀的富集。笔者对钱家店钱Ⅱ块铀矿床红色泥砾砂岩的岩石学特征、U和Ra含量特征进行了分析,结果表明,红色泥砾砂岩形成于还原性沉积环境,铀矿化主要在沉积成岩期富集而成。红色泥砾砂岩在成岩期后遭受氧化并发生铀的迁移。

Petrological Characteristic and Mineralization Analysis of Red Muddy Gravelled Sandston in Qianj iadian Uranium Deposit

Ore bearing sequence in Qianjiadian sag is mainly the Upper Cretaceous Yaojia formation.In the exploration,the red muddy gravel sedimentation is often found with uranium enrichment in Yaojia for-mation.According to the result of petrological characteristic and content of uranium and radium analysis, the red muddy gravel was originally formed in reducing environment and the uranium enrichment was controlled by reduction condition in deposition diagenesis stage which made the uranium precipitation and enrichment possible.Oxidation after diagenesis made the sediment turning into red and cause the acti-vation and migration of uranium.