广西十万大山盆地大廖地区铀储层砂体沉积特征及与铀矿化关系  

Sedimentary characteristics of uranium reservoir sand body and its relationship with uranium mineralization in Daliao area,Shiwandashan Basin,Guangxi

作　　者：李晓友 叶少剑 LI Xiaoyou;YE Shaojian(Guangxi Nuclear Geological Party No.305,Liuzhou 545000,Guangxi,China)

机构地区：[1]广西壮族自治区三○五核地质大队,广西柳州545000

出　　处：《矿产与地质》2023年第2期265-270,278,共7页Mineral Resources and Geology

基　　金：广西壮族自治区地质矿产勘查开发局“广西十万大山盆地砂岩型铀成矿规律与找矿预测研究”资助。

摘　　要：广西十万大山盆地铀矿化层位多,不同矿化层位铀储层砂体沉积特征不同,在后期富集成矿过程中所起作用不同。在综合前人研究成果的基础上,通过野外地质调查、剖面对比、钻孔岩心观察,系统分析了大廖地区那荡组上段铀储层砂体岩性岩相、沉积构造以及砂体展布特征,认为大廖地区那荡组上段铀储层砂体为辫状河三角洲沉积体系,发育三角洲前缘亚相沉积,主要的控矿微相为水下分流河道;砂体呈厚薄相间透镜状形态,整体表现为“下粗上细”的特征;铀矿(化)体主要赋存在砂体中下部,且与砂体厚度呈明显的正相关关系。综合上述研究,初步预测大廖地区铀成矿的有利区块,为大廖地区铀资源勘查工作提供依据。There are many uranium mineralization rock layers in Shiwandashan Basin,Guangxi,and the sedimentary characteristics of uranium reservoir sand bodies in different mineralization rock layers are different from each other.They play the different roles in the later enrichment and mineralization process.On the basis of previous research result,through geological field survey,geological profile comparison and drilling hole core observation,the lithology,lithoface,sedimentary structure and distribution characteristics of uranium reservoir sand bodies at the upper section of Nadang Formation in Daliao area are systematically summarized and analyzed.It is considered that the uranium reservoir sandstone bodies at the upper section of Nadang Formation in Daliao area are the sedimentary system of braided river delta with delta front subface,and the main ore-controlling microfacies are underwater distributary channel.The sand body has a lenticular shape with thick and thin phase,and the overall performance is"coarse at the bottom and fine at the top".Uranium ore body(mineralized belt)mainly occurs in the middle and lower part of sand body,which has an obvious positive correlation with the thickness of sand body.Through the above research,the favorable target areas for uranium mineralization in Daliao region are preliminarily predicted.It can provide a basis for the uranium resources exploration in Daliao area.

关 键 词：铀储层砂体 沉积特征 控矿微相 水下分流河道 十万大山盆地 广西 

分 类 号：P619.14[天文地球—矿床学]