论文部分内容阅读
我国沉积变质型铀矿床主要产在华北地台的太古界、元古界的变质岩系中,都在古老基底剥蚀面之上,有花岗岩侵入或混合岩化。古地理环境为滨海-浅海相中近古海岸线的基底洼地。矿化特点因地段不同而异:远离花岗岩地段,矿体呈似层状,与地层产状基本一致,受层位、岩性控制,铀矿物是沥青铀矿,粒度小,沿层理定向排列;近花岗岩外接触带或混合岩化地段为巢状矿体,铀矿物是晶质铀矿,粒度大,呈脉状、网脉状产出。与国外澳北区铀矿床相比,两者基本相似,但我国铀矿化分布空间大,形成时间长,无盖层。矿床形成过程为:沉积阶段形成了富铀
Sedimentary metamorphic uranium deposits in China are mainly produced in Archean and Proterozoic metamorphic rocks in North China, all of which are on the surface of ancient basement denudation with intrusive or mixed granitization of granite. Paleogeographic environment is the basal depression in the coastal-shallow marine facies of the ancient coastline. Mineralization characteristics vary with the location: away from the granite area, the ore body was stratified, consistent with the formation of stratum, controlled by the horizon, lithology, uranium minerals are uranium ore, small size, along the bedding orientation ; Near granite outer contact zone or mixed rock area for the nested ore body, uranium mineral is crystalline uranium ore, granularity, vein, reticular output. Compared with the uranium deposit in Obei area, the two are basically similar, but the space for uranium mineralization in our country is large and formed for a long time without caprock. The formation process of the deposit is as follows: enriched uranium is formed in the depositional stage