蒙其古尔铀矿床西山窑组下段砂岩型铀矿沉积环境

Sedimentary Environment of the Sandstone Type Uranium Deposit of the Lower Section of Xishanyao Formation of Mengqiguer Uranium Deposit

以蒙其古尔铀矿床西山窑组下段为例,在分析区域地质背景的基础上,首先基于综合测井资料,根据综合解译结果统计研究层位的砂体厚度,绘制研究层位砂体厚度等值线图,分析研究层位的砂体平面展布特征;然后统计研究层位的视电阻率均值,绘制研究层位的视电阻率均值(砂体粒度)等值线图,分析研究层位的砂体粒度平面展布特征,进而分析研究层位的沉积环境。在上述分析的基础上,讨论了蒙其古尔铀矿床西山窑组下段沉积相与铀成矿的关系,认为在扇三角洲平原分流河道砂体中,砂岩型铀矿体的展布明显受沉积微相尤其是辫流岛发育部位、大小和形态的控制。分析结果对于该区进一步开展砂岩型铀矿找矿勘探工作有一定的借鉴价值。

Taking the lower section of Xishanyao formation of Mengqiguer uranium deposit as the study example,the regional geological background is analyzed,firstly,based on the comprehensive interpretation results of the comprehensive logging data of the study area,the sandbody thickness data of the study position is obtained,and the contour map of sandbody thickness is made to analyze the plane distribution characteristics of sandbody; then,according to the average value of apparent resistivity of the study position,the contour map of the average values of apparent resistivity（ sandbody size） of the study position is obtained to discuss the plane distribution characteristics of the sandbody size of the study position to conduct further analysis on the sedimentary environment of the study position. Based on the above analysis results,the relationship between sedimentary facies and uranium metallogenic of the lower section of Xishanyao formation of Mengqiguer uranium deposit is studied,the results show that the sandstone type uranium deposit is significantly controlled by the sedimentary microfacies especially for the position,size and shape of the development of braided stream island. The above analysis related to the sedimentary environment of the sandstone type uranium deposit of the lower section of Xishanyao formation of Mengqiguer uranium deposit can provide some reference for the further prospecting and exploration work of the uranium deposit in the area.