鄂尔多斯盆地北缘砂岩型铀矿综合地质背景分析  

Comprehensive analysis of geological background of sandstone-type uranium deposits in northern margin of Ordos Basin

作　　者：陈靖霖 张原庆[1] 程银行 CHEN Jinglin;ZHANG Yuanqing;CHENG Yinhang(Institute of Mineral Resources Prediction of Synthetic Information,Jilin University,Changchun 130026,China;Tianjin Center,China Geological Survey,Tianjin 300170,China)

机构地区：[1]吉林大学综合信息矿产预测研究所,长春130026 [2]中国地质调查局天津地质调查中心,天津300170

出　　处：《世界地质》2023年第3期472-478,共7页World Geology

基　　金：国家自然科学基金项目(92162212);973项目(2015CB453000)联合资助。

摘　　要：鄂尔多斯盆地北缘是中国砂岩型铀矿重要矿集区之一。通过盆地铀成矿地质、航磁、重力、放射性、遥感等数据研究,发现盆地北缘重磁异常存在明显的环带异常和东西向与北北东向局部异常叠加,古河流具有明显的遥感和重磁异常显示。笔者认为盆地北缘东西向构造叠加北北东向构造是控制古河流沉积的主要因素,间接控制氧化还原环境及铀矿床的形成。古河流自北向南流动由北东向构造控制,盆地东西向构造形成南北向台阶,在构造台阶控制下河流形态呈直流河-曲流河-辫状河-湖发展。沉积物粒度由粗至细变化,沉积环境由氧化-过渡-还原变化,铀矿沉积主要位于辫状河与湖盆交互位置。The northern margin of Ordos Basin is one of the important ore concentration areas of sandstone-type uranium deposits in China.[JP2]Based on the study of uranium metallogenic geology,aeromagnetic,gravity,[JP]radioactivity,remote sensing,it is found that there are obvious girdle anomalies in the gravity and magnetic anomalies and the superposition of local anomalies in the east-west and north-north-east directions in the northern margin of the basin.The ancient river has obvious in remote sensing and gravity and magnetic anomalies.The authors consider that the east-west structure superimposed on the NNE striking structure in the studying area is the main controlling factor for the deposition of ancient rivers,indirectly controlling the redox environment and the formation of uranium deposits.The north to south flow of ancient rivers is controlled by the northeast trending structure.The east-west structure of the basin results in[JP2]a south-north step.Under the control of the structural step,the river morphology develops in a straight stream-meandering stream-braided stream-lake.The grain size of the sediments changes from coarse to fine,and the sedimentary environment shows a change from oxidation to reduction with transition in between.The uranium deposits are mainly located in the interaction area between river and lake basin.[JP]

关 键 词：砂岩型铀矿 地质背景 鄂尔多斯盆地北缘 

分 类 号：P619.14[天文地球—矿床学]