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不列颠哥伦比亚中南部基底型铀矿床产于奥卡纳甘高原侵入杂岩内主断裂带之上的晚中新世古河道沉积岩中。在矿化未形成之前,赋存含矿沉积岩的古洼地被上新世高原玄武岩覆盖。到目前为止已圈出五个铀矿床。其中的布里泽德(4,020吨铀)和泰伊(650吨铀)矿床是最大的。对杂岩的构造分析表明,这是一个由断层和裂隙系统相互贯通的结构松散体,它能够维持发育良好的中等性和区域性的地下水流系统的畅通。赋存矿化的沉积岩由砾岩、长石砂岩和泥岩组成。在许多矿化层(但不是整个)中有机质很丰富。铀矿化是以亚铀(人形石)或铀酰(镁磷铀云母、钙铀云母)磷酸盐形式出现,呈薄膜包裹碎屑颗粒或充填孔隙。人形石是泰伊矿床唯一的铀矿物,而布里泽德矿床则具有一个更复杂的矿物组合(镁磷铀云母、钙铀云母、人形石)。布里泽德矿床中有少量的Zn、Ni、Co和Mo,而在泰伊矿床中,只富集非成矿元素Mo。在这两个矿床中,Mn是唯一的贫化元素。矿化形成时期的古气候特点是温和的气候,并伴随有中等程度均匀分布的降雨。对成矿元素(U、Ca、Mg、PO_4)来源的研究得出的结论是:这些元素是由于地下水淋滤奥卡纳甘高原侵入杂岩而得来的。通过研究表明,含矿的地下水是冷的、弱重碳酸盐化的(150—400 ppm)、富铀的(10—50 ppb),并且是弱氧化的(溶解氧2—4 ppm)。此外,含矿的地下水具有足够数量的Ca、Mg和PO_4。当地下水进入含矿沉积岩时,由于有机酸的形成和铁硫化物的氧化而被迅速地酸化。矿化形成在拉张构造时期(晚中新世至早上新世)之后,造陆运动时期(晚上新世至更新世隆起)之前。矿化形成于4至1百万年期间。
Central-southern British Columbia basement uranium deposits are produced in late-Miocene sedimentary rocks above the main fault in the intrusive complex of the Okanagan Plateau. Prior to mineralization, paleo-depressions containing ore-bearing sedimentary rocks were covered by Upper Pleistocene basalts. To date, five uranium deposits have been circled. Among them, Brideside (4,020 tonnes of uranium) and Tai (650 tonnes of uranium) deposits are the largest. Tectonic analysis of the complex shows that it is a structurally loose body interpenetrated by fault and fracture systems that maintains the well-developed flow of moderate and regional groundwater flow systems. The mineralized sedimentary rocks consist of conglomerates, feldspathic sandstones and mudstones. Organic matter is abundant in many (but not all) layers of mineralization. Uranium mineralization takes the form of uranium (chevron) or uranyl phosphate (mica, uranium mica) in the form of phosphates, wrapping detrital particles or filling pores in thin films. The pebble is the only uranium mineral in the Tyu deposit, while the Brzezter deposit has a more complex mineral assemblage (Mg-U-mica, Ca-U-mica, man-made stone). The Brizzled deposit contains a small amount of Zn, Ni, Co and Mo, whereas in the Taiy deposit, only the non-metallogenic element Mo is enriched. In both deposits, Mn is the only element depleted. Paleoclimate during mineralization was characterized by a mild climate accompanied by moderately uniform rainfall. The study of the origin of metallogenic elements (U, Ca, Mg, PO_4) concluded that these elements were derived from intrusion of Okanagan plateaus into the porphyry by groundwater leaching. Research shows that ore-bearing groundwater is cold, weakly carbonated (150-400 ppm), uranium-rich (10-50 ppb), and weakly oxidized (2-4 ppm dissolved oxygen). In addition, mine-bearing groundwater has a sufficient amount of Ca, Mg and PO 4. As the local water enters the ore-bearing sedimentary rocks, it is rapidly acidified due to the formation of organic acids and the oxidation of iron sulphides. Mineralization occurred during the extensional tectonic period (Late Miocene to Early Pliocene) and before the land-making movement (Late Pliocene to Pleistocene uplift). Mineralization is formed between 4 and 1 million years.