鄂尔多斯盆地纳岭沟铀矿床铀矿物特征与形成机理
发布时间：2019-06-05 11:56
【摘要】：纳岭沟铀矿床位于鄂尔多斯盆地北东部,是我国近年发现的一个特大型砂岩铀矿床,铀矿体赋存于中侏罗统直罗组下段河流相砂体中,受古层间氧化带控制,呈板状。铀矿物主要为铀石、沥青铀矿和钛铀矿,其中铀石是最主要的铀矿物。沥青铀矿中w(CaO)较高;铀石中w(UO_2)偏低、w(SiO_2)偏高,w(UO_2)/w(SiO_2)达到1:1.29,远低于正常值;钛铀矿则呈现U低Ti高的特点。根据各铀矿物的形成、富集机理,认为纳岭沟铀矿床在古层间氧化发育阶段赋矿砂体属于酸性环境,SiO_2活度较低,形成铀矿物主要为沥青铀矿。始新世晚期及以后,氧化作用不发育,赋矿砂体被二次还原,岩石地球化学环境由酸性转变为弱碱性,SiO_2活度增大,使早期阶段形成的沥青铀矿转变为铀石。钛铀矿主要是在氧化—还原作用下由含铀溶液中的铀(UO_2~(2+))交代重矿物—钛铁矿中的Fe2+而形成。
[Abstract]:Naling Gou uranium deposit is located in the north east of Ordos Basin. It is a very large sandstone uranium deposit discovered in China in recent years. The uranium orebody occurs in the fluvial sand bodies of the lower member of the Zhiluo formation of the Middle Jurassic, and is controlled by the paleo-interlayer oxidation zone and is in the shape of a plate. Uranite is mainly composed of uranite, pitchblende and ilmenite, among which uranite is the most important uranite. The w (CaO) in pitchblende is higher than that in uranite, and the ratio of, w (UO_2 / SiO_2 in uranite is 1 鈮，
本文编号：2493509
[Abstract]:Naling Gou uranium deposit is located in the north east of Ordos Basin. It is a very large sandstone uranium deposit discovered in China in recent years. The uranium orebody occurs in the fluvial sand bodies of the lower member of the Zhiluo formation of the Middle Jurassic, and is controlled by the paleo-interlayer oxidation zone and is in the shape of a plate. Uranite is mainly composed of uranite, pitchblende and ilmenite, among which uranite is the most important uranite. The w (CaO) in pitchblende is higher than that in uranite, and the ratio of, w (UO_2 / SiO_2 in uranite is 1 鈮，
本文编号：2493509
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