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新墨西哥州西北安布罗西亚湖地区是美国最重要的采铀区和冶炼区。它和附近的拉古纳(Laguna)地区共占国家储量的50%以上。大部分矿石产于晚侏罗世莫里松建造(Morrison formation)内,主要赋存在威斯特瓦特肯杨叚砂岩的上部及靠近普伊松(Poison)肯杨砂岩舌的底部,矿体呈延长状、板状及馒顽状。各个矿床都是沿着两个相隔为2到3英里的向东延伸的矿带分布。矿体长3,000尺,宽几百尺,厚100尺。矿化深度变化在0到2,200尺。某些矿石采自晚侏罗世托迪尔吐(Todilto)灰岩及早?和晚白垩世达克塔(Dakota)砂岩内。有两个公认的未氧化矿石类型:断层前(Prefault)矿石被认为是原生的,而断层后(Pastfault)矿石可能是再分配的。断层前矿石显示与大地构造没有明显的关系,但受一种沉积构造所控制。断层后矿石受沉积构造和大地构造综合的控制。散染状含炭物质对铀的富集显示出最有力的控制,我们认为它是由植物演变而来。矿石的矿物学比较简单,最大量的矿石矿物是铀石。在矿床中氧化及未氧化的矿物里,钼、硒、钒及铁都达到了异常的含量。u/eu 的比率和放射性同位素的分布,显示出几乎是普通的不平衡,在已取样的所有矿床中,放射性同位素均有最现代的迁移。需要进一步研究有机炭质物、砂岩蚀变、年龄测定及硫同位素成分,才能对此矿床中的铀及其他元素的来源、搬运和沉淀取得更好的了解。
The Amblesia Lake area northwest of New Mexico is the most important uranium mining and smelting area in the United States. It and the nearby Laguna region together account for more than 50% of state reserves. Most of the ore produced in the late Jurassic Morrison formation (Morrison formation), mainly in the West Watertanken poplar sandstone and close to the bottom of the Poison Kenyan sandstone tongue, ore body was Extended shape, plate-shaped and steamed bun stubborn. Each deposit is distributed along two east-extended ore zones that are 2 to 3 miles apart. The orebody is 3,000 feet long, hundreds of feet wide and 100 feet thick. Mineralization depth varies from 0 to 2,200 feet. Some of the ore was collected from the late Jurassic Todilto limestone in the early and late Cretaceous Dakota sandstones. There are two recognized types of unoxidized ore: Prefault ore is considered native, whereas Pastfault ore may be redistributed. Pre-fault ore shows no obvious relationship with the tectonics, but is controlled by a sedimentary structure. After the fault ore by the sedimentary structure and integrated control of the earth structure. Scattered carbonaceous material shows the most powerful control over uranium enrichment, and we think it evolves from plants. Ore mineralogy is relatively simple, the largest amount of ore minerals are uranium. In the minerals that are oxidized and not oxidized in the deposit, molybdenum, selenium, vanadium and iron all reach anomalous contents. The u / eu ratio and the distribution of radioisotopes show almost normal imbalances, with the most modern radioisotope migration in all sampled deposits. Further study of organic carbonaceous matter, sandstone alteration, age determination and sulfur isotopic composition is needed to gain a better understanding of the source, transport and precipitation of uranium and other elements in this deposit.