基准面旋回在砂岩型铀矿勘查中的应用--以东胜铀矿床为例

近年来以基准面旋回为参照面的高分辨率层序地层学迅速发展,其最大的优势在于能够适用于受多重因素控制的陆相沉积盆地,并有效提高层序地层分析的准确度和分辨率。基准面旋回原理也同样适用于砂岩型铀矿的勘探开发研究和实践,它控制了砂岩、泥岩的空间分布和岩石孔渗、封闭性能,决定了地层结构的叠加样式。文章以东胜铀矿床为例,分析了基准面旋回在砂岩型铀矿勘探开发中的应用。认为:基准面升降旋回中形成的砂、泥岩地层结构配置良好;长期基准面上升早期形成的辫状河河道砂岩具连通性好、粒度粗、碎屑含量高、杂基含量低及孔渗条件好等特点,是重要的含矿层。

Application of base-level cycles to sandstone-type uranium deposit: taking Dongsheng uranium deposits as an example

High-resolution sequence stratigraphy taking base-level cycles as interface of reference was developed rapidly in recent years.Its greatest predominance lies in that it can be applied to multi-controled continental sedimentary basins and can effectively improve accuracy and distinguishability of sequence stratigraphy analysis.Principles of base-level cycles can also be applied to the research and practice of the exploration and exploitation of sandstone-type uranium deposits as they control the spatial distribution,porosity,the permeability and the sealing ability of sandstone and mudstone,and stacking patterns of strata configuration.Taking Dongsheng uranium deposits as an example,the application of base-level cycles to exploration and exploitation of sandstone uranium deposits was analyzed.It is suggested that favorable strata framework of sandstone and mudstone was developed very well in the fluctuation of base-level cycles.Sand bodies were provided with good connectedness,coarse granularity,high debris content,low matrix content and good porosity-permeability becoming the most important uranium hosted strata.