摘要
一七九岩体接触带产有铀矿床。该矿床矿石组合为沥青铀矿-金属硫化物-方解石。赋矿岩石为晚元古代浅变质岩、晚古生代碳硅泥岩及印支期花岗岩等围岩中的碎裂岩。该矿体既具花岗岩型铀矿的一般特征(如受岩体和断裂构造控制,与该岩体内的微晶石英型铀矿床,有着密切的时空和成因联系),也有自身的某些特点(如沥青铀矿主要沉淀于碳酸盐热液期,在成因上具多源性和复成性,属混合热液型);在成矿地质背景方面,具铀源条件较差、碳酸盐岩与水云母化发育等再要特色。矿床属花岗岩型铀矿中的一个特殊类型。
The No. 179 rock body is an Indo-Siuian complex granite body. Along its contact zone occurs a carbonate type uranium deposit which has the characteristic association of pitchblende-metallic sulfides-calcite. Pitchbler de-calcite veins occur in cataclasite zones within such wall rocks as late Proterozoic epimetamorphic rocks, late Paleozoic carbonaceous siliceous mudstone and Indo-Sinian granite.Uranium mineralization in this ore deposit is mainly controlled by granite body and fracture structures; uranium mineralization is chiefly in the form of colloidal filling and possesses obvious poly-stage characters; the rock-forming temperatures are 130—200℃, belonging to mesothermal-epithermal type; ura(?)ium mineralization age is 60Ma, indicating a rather great time difference between the ore and the rock; this ore deposit has a quite close temporal-spatial and genetic connection frith the microcrystalline quartz type uranium deposit in the granite body. All these phenomena suggest that this ore deposit possesses the common characteristics of the granite type uranium deposits.The ore deposit also shows lots of its own features: the apparent difference in sulfur, oxygen and carbon isotope determinations between mineralization veins of the two stages suggests that their ore-forming substances came from the depth and the near-svface places respectively; uranium was extracted (?)interruptedly through different means from different solid rocks with different depths; uranium mineralization belongs to acid siliceous stage and carbonate hydrothermal stage (corresponding to calcium deposition stage of granite type uranium deposits); the ore deposit is genetically of mixed hydrothermal type and is fundamentally different from the microcrystalliue quartz type uranium deposit. This ore deposit, herefore, is of a special type in granite type uranium deposits.
出处
《矿床地质》
CAS
CSCD
北大核心
1990年第1期56-62,共7页
Mineral Deposits
