砂岩型铀矿地浸开发的地质保障—— 含矿含水层微观非均质性研究

随着当前国内砂岩型铀矿床的大规模开发，含矿含水层的非均质性对地浸采铀的影响逐步显现。针对砂岩型铀矿的矿层非均质性，应用岩心CT扫描、铸体薄片、SEM等分析手段，以国内两大典型砂岩型铀矿层为例，从定性和定量两个方面剖析了含矿层的矿物成分非均质性及对地浸采铀的影响。研究表明，二连盆地赛汉组下段含矿层适合酸法地浸，地层胶结弱，孔隙性、渗透性好，有利于地浸液在矿层充分运移。鄂尔多斯盆地直罗组矿层的空间主要以连通性较好的粒间孔隙为主，由于埋藏较深，矿层较赛汉组致密，地层渗透性差于赛汉组。最后，总结了微观实验方法带来的非均质性分析局限性，对宏观非均质性分析手段进行了展望。

Geological Guarantee for In-situ Leaching Development of Sandstone-type Uranium: Study on Microscopic Heterogeneity of Ore-bearing Aquifer

With the large-scale development of sandstone-type uranium deposits in China, influence of ore-bearing aquifer heterogeneity on in-situ leaching uranium mining gradually appears. In view of ore-bearing aquifer heterogeneity of sandstone-type uranium deposit, the experiment results of core CT scanning, thin section, SEM, and other microscopic analysis were summarized and analyzed. Applying two typical sandstone-type uranium deposits in China as examples, the mineral composition heterogeneity of sandstone-type uranium deposit and its influence on in-situ leaching uranium mining were analyzed from qualitative and quantitative aspects. The results show that Saihan Formation in Erlian Basin is suitable for acid in-situ leaching, the formation cementation is weak, the porosity and permeability are good, which is conducive to full migration of in-situ leaching solution in ore bed. The space of Zhiluo Formation in Ordos Basin is mainly intergranular pores with good connectivity. Due to deep burial, Zhiluo Formation is denser than that of Saihan Formation, and the permeability is worse than that of Saihan Formation. Finally, the limitations of heterogeneity analysis brought from microscopic experimental methods were summarized, and the macroscopic heterogeneity analysis methods were prospected.