鄂尔多斯盆地北部下白垩统砂岩型铀成矿机理与找矿成果  

Metallogenic Mechanism and Exploration Achievements of Sandstone-type Uranium in the Lower Cretaceous Strata of the Northern Ordos Basin

作　　者：剡鹏兵 王龙辉 李华明 胡立飞 郭涛 平智伟 刘斌 YAN Pengbing;WANG Longhui;LI Huaming;HU Lifei;GUO Tao;PING Zhiwei;LIU Bin(Geologic Party No.208,CNNC,Baotou 014010,China)

机构地区：[1]核工业二〇八大队,内蒙古包头014010

出　　处：《东华理工大学学报（自然科学版）》2024年第5期409-420,共12页Journal of East China University of Technology(Natural Science)

基　　金：中国核工业地质局地勘费项目“鄂尔多斯盆地北部鄂托克前旗-东胜地区铀矿资源调查评价与勘查”(202201)。

摘　　要：为进一步扩大鄂尔多斯盆地北部的找矿成果,通过盆地北部下白垩统施工的铀地质孔,结合区域构造资料、区内剖面对比、岩芯识别和化学测试等,构建了下白垩统的地层格架,分析了其砂岩型铀成矿机理。结合已有的找矿成果,总结了下白垩统的地球化学特征和矿化特征,认为含矿层环河组主要划分为冲积扇、辫状河、辫状河三角洲和湖泊沉积体系,矿体主要分布于相变部位。矿体在平面上富集于未完全氧化带内,且靠近还原带一侧,垂向上矿体位于氧化带向还原带过渡的未完全氧化带中。进一步完善了下白垩统的成矿模式,预测了鄂尔多斯盆地北部下白垩统各层位的找矿远景区,预测有一级远景区2处、二级远景区1处、三级远景区3处。In order to further expand the exploration achievements in the northern part of the Ordos basin,a stratigraphic framework of the Lower Cretaceous strata was constructed through uranium geological boreholes constructed in the northern part of the Ordos basin,combined with regional structural data,and comparison of regional profiles,core identification,chemical testing,etc.The sandstone type uranium mineralization mechanism was analyzed,and combined with existing exploration results,the geochemical and mineralization characteristics of the Lower Cretaceous strata were summarized.The main ore bearing layers of the Huanhe Formation are mainly divided into alluvial fans,braided rivers,braided river deltas,and lake sedimentary systems.The ore bodies are mainly distributed in the phase change areas.It is believed that the ore body is enriched in the incomplete oxidation zone on the plane,and is close to the side of the reduction zone.Vertically,the ore body is located in the incomplete oxidation zone that transitions from the oxidation zone to the reduction zone.The mineralization model of the Lower Cretaceous strata was further improved,and the prospective areas of each layer of the Lower Cretaceous strata in the northern part of the Ordos basin were predicted.It is predicted that there will be 2 first level prospective areas,1 second level prospective area,and 3 third level prospective areas.

关 键 词：铀成矿 下白垩统 找矿成果 鄂尔多斯盆地北部 

分 类 号：P619.14[天文地球—矿床学]