准噶尔盆地东北部侏罗系砂岩型铀矿成矿环境与找矿方向探讨

文章从蚀源区铀源条件、中新生代构造演化条件、侏罗系沉积建造特征及后生蚀变特征等角度分析了准噶尔盆地东北部砂岩型铀矿的区域成矿条件,认为卡拉麦里山的富铀花岗岩体为该区砂岩型铀成矿提供了丰富的铀源,中侏罗统含煤碎屑岩建造为砂岩型铀成矿提供了良好的容矿空间,侏罗纪以来多期次不整合面的发育为含铀含氧水的渗入改造提供了通道及时间,为大规模层间氧化带的发育提供了物质基础。研究结果显示,卡拉麦里山北坡为最有利的砂岩型铀矿找矿部位,其主要找矿目标层位为中侏罗统头屯河组,找矿类型为层间氧化带型。

A study of metallogenic environments and prospecting direction of Jurassic sandstone-type uranium deposit in northeastern Junggar Basin

From various aspects such as uranium source, Mesozoic-Cenozoic tectonic evolution, Jurassic sedimentary characteristics and features of epigenetic alteration, this paper analyzes the metallogenic conditions of the sandstone-type uranium deposit in the northeast of Junggar basin. The authors propose that the U-rich granitiod intrusives provided abundant uranium sources, and the Middle Jurassic coal-bearing clastic sedimentary formation possessed favourable stratigraphic combinations for the development of sandstone-type uranium deposit. The unconformity formed in the Jurassic period showed that it had a channel and a time span for the reformation process of interlayer water with oxygen and uranium, which provided a material basis for the large-scale development of interlayer oxidation zone. It is thus held that the northern slope of Kalamali Mountain is the most favorable area for uranium prospecting, the main target horizon is Middle Jurassic Toutunhe Formation, and the prospecting type is interlayer oxidation zone type sandstone uranium deposit.