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由于新鲜的大气地下水造成的侧分泌,导致在沉积岩中形成铀矿,这是一个流行的理论。然而野外研究表明,流动的新鲜的地下水不能在蓄水层成矿。铀、铜、和钒矿床是由能侵蚀并克分渗透和造成不透水岩石蚀变的溶液形成的。铀成矿作用发生在一定的地区内,并不是在任何具有相应的来源和貯集岩石的动力水系统都能成矿。铀矿区是沿着活动带的前陆集中分布的,而最好的源岩则是在后陆。在区域内大面积首先形成的铀矿,共分布与大的构造裂隙有关,而与地形表面、地层、局部构造或局部动力水系统的关系较小。目前,在地区上分布均匀的铀含量见于含铀来源最多的岩石——花岗岩、流纹凝灰岩和炭质页岩,这表明这些岩石能抵抗普通水的淋滤。部分铀可被酸淋滤而迁移。铀矿床也含有一组微量元素;在数量上此在源岩内的含量要超过几个数量级。其中某些元素并不是很容易被淋滤出来的。铀矿床的蚀变岩石的类型并不反映新鲜水的流动,但却被选择性地限制在类似的化学环境中,并且局部有时发生变化,这表明流体的来源供给不足。困难的是要通过扩散使离子浓集到足够数量或是通过水的流动造成矿石沉积,这就要求探讨一种浓集的流体。对新鲜水分析表明,铀矿床内的一组元素含量,要比源岩中的含量少许多倍,而卤水中元素含量的浓度则比源岩要高许多倍,甚至于接近矿石中的富集程度。砂岩铀矿床中的方解石波-气包体表明卤水是在45℃—65℃被捕集的。最近同位素研究表明,许多卤水是由于富含矿物离子的大气水渗透通过受热环境而成。含铀矿化流体必须有腐蚀性、穿透性、选择性和富集作用,而新鲜地下水却没有这种性质。矿化流体可能是卤水,这种卤水是由大气水与岩浆水、原生水或来自任何源岩的岩石结晶流体和矿物离子相混合而组成的。这种矿化流体根据温度分带而迁移和成矿。
It is a popular theory that the side secretions caused by fresh atmospheric groundwater lead to the formation of uranium deposits in sedimentary rocks. However, field studies show that fresh groundwater flowing can not mineralize in aquifers. Uranium, copper, and vanadium deposits are formed by solutions that can erode and gage infiltrate and cause alteration of impervious rocks. Uranium mineralization occurs in a certain area, not in any dynamic water system with corresponding source and reservoir rocks. Uranium mines are concentrated along the foreland of the active belt, while the best source rock is backfired. The first large-area uranium deposits formed in the area are associated with large structural fractures, but have little to do with surface topography, strata, local structures or local dynamic water systems. At present, the uranium content distributed uniformly in the area is found in the rocks with the most uranium sources - granite, rhyolite tuff and carbonaceous shale, indicating that these rocks can resist the leaching of ordinary water. Part of uranium can be leached by acid and migrated. Uranium deposits also contain a group of trace elements; this amount is more than a few orders of magnitude greater in source rocks. Some of these elements are not easily leached out. The type of altered rock in a uranium deposit does not reflect the flow of fresh water, but is selectively confined to a similar chemical environment and changes locally in some cases, indicating that the fluid source is under-supplied. It is difficult to concentrate the ions to a sufficient amount by diffusion or deposit the ore by the flow of water, which requires exploration of a concentrated fluid. Analysis of fresh water shows that a group of elements in a uranium deposit are many times less abundant than those in the source rock and elemental concentrations in the brine are many times higher than those in the source rock and are even close to the enrichment in the ore degree. Calcite-gas inclusions in sandstone-type uranium deposits indicate that brine is trapped at 45 ° C-65 ° C. Recent isotope studies have shown that many brines are formed by the permeation of atmospheric water rich in mineral ions through a heated environment. Uranium-containing fluids must be corrosive, penetrating, selective, and enrichment, whereas fresh groundwater has no such properties. The mineralized fluid may be brine, which is composed of atmospheric water mixed with magmatic water, virgin water, or rock crystalline fluids and mineral ions from any source rock. This mineralized fluid migrates and mineralizes according to temperature zoning.