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美国的铀矿储量约40％产在怀俄明州的矿卷型矿床(每磅U_3O8为8美元即可开采)。含矿主岩是长石砂岩,它是在河成条件下的山间盆地沉积物,是由盆地两翼山脉花岗岩风化壳供给的碎屑物质。主岩是始新世也可能有古新世的岩石。上复岩层依次为陆相凝灰质粉砂岩、砂岩和砾岩,厚度为400—700米。多数矿石是未氧化的,并位于潜水面以下。它含有黄铁矿,晶质钠矿,铀石,白铁矿,赤铁矿,白硒铁矿和自然硒■。卷状铀矿体的大小,其矿石量可从几百吨到几十万吨,U_30_8的含量为0.1—3％,从开采来看,矿石平均品位约为0.25％U_30_8。矿体在成因上与大的舌状蚀变砂岩有联系,并位于它的边缘。蚀变的特点和某儿种元素分布征蚀变砂岩中及其附近的情况表明,含矿溶液是中性到弱碱性、并能氧化有关的迁移元素的地下水。最近在得克萨斯州墨西哥湾海岸平原区滨海相和河相砂岩中发现卷型矿床。达些矿床纯形态、元素分布和成因上与怀俄明矿床是类似的。
Approximately 40% of the U.S. uranium deposit is produced in the Wyoming wurtzite deposit (US $ 8 per pound U_3O8). The ore-bearing host rocks are feldspathic sandstones, which are sediments of the mountain basin under river conditions and are clastic materials supplied by the weathering crust of the granites in the flank ranges of the basin. The main rock is the Eocene may also have the Paleocene rock. The upper strata are, in turn, continental tuffaceous siltstones, sandstones and conglomerates with a thickness of 400-700 meters. Most of the ore is unoxidized and lies below the surface of the dive. It contains pyrite, crystalline sodium, uranium, white iron ore, hematite, selenite and natural selenium ■. The size of the rolled uranium ore body, the ore volume can be from hundreds of tons to hundreds of thousands of tons, U_30_8 content of 0.1-3%, from the mining point of view, the average grade of ore is about 0.25% U_30_8. The orebody is genetically linked to a large, tongue-like altered sandstone and is located on its periphery. The characteristics of alteration and distribution of some kinds of elements show that the ore-bearing solution is neutral to weakly alkaline and can oxidize the related groundwater of migratory elements. Recently, curl deposits were found in the coastal facies and fluvial sandstones of the coastal plains of the Gulf of Mexico in Texas. The pure morphology, elemental distribution and genesis of these deposits are similar to the Wyoming deposits.