The "potential uranium reservoirs" refer to as the sandstone and conglomerate horizons with the natural gamma-ray values of more than 50 γ( or 3. 5 PA/kg, or 150 api, or 12. 6 ( n-C)/kg-h) in well logs from the coalfield data, which reflects, more or less, special uranium mineralization information in the deeper parts of basins. The present paper focuses on tectonic setting, palaeoclimatology, uranium sources, hydrogeology, lithology, sedimentary facies and uranium potential in the Husa Basin, western Yunnan. Although the Husa Basin is not located in the best favourable exploration area, the dual inversion of tectonics and climates in the Neogene and Quaternary, and the presence of higher natural gamma-ray values and greater thickness may facilitate to the uranium mineralization in the Basin. According to the statistical analysis of the radioactive anomalies and sedimentary characteristics of the"potential uranium reservoirs", referenced to the previous results, the exploration targets are delineated in the first and second members of the Mangbang Formation in the steep slope fan delta facies and ramp alluvial fan facies.%"潜在储铀层"指煤田等勘探钻孔测井资料中自然伽马值显示高于50γ(或3.5PA/kg或150api或12.6纳库(n·C)/kg·小时)所对应的砂岩、砾岩层,其在一定程度上反映了盆地深部特殊的铀矿化信息.据此,为探讨滇西首个"煤铀兼探"优选靶区即户撒盆地砂岩型铀矿的成矿条件与找矿方向,本文从煤田"潜在储铀层"提供的深部铀矿化信息入手,在系统分析盆地构造、古气候、铀源、水文地质、岩性岩相五项成矿要素后,结合前人区域研究成果,认为户撒盆地具有一定的成矿条件与找矿潜力."潜在储铀层"放射性特征与沉积学特征统计分析指示盆地找矿主攻层位应为芒棒组一、二段,找矿主攻相带应为陡坡带扇三角洲相和缓坡带冲积扇相.上述认识已得到钻探成果的初步证实.
展开▼
