铀矿地质2024，Vol.40Issue(4)：619-632,14.DOI:10.3969/j.issn.1000-0658.2024.40.056
松辽盆地开鲁坳陷上白垩统姚家组与青山口组地层发育特征及铀成矿条件
Development Characteristics and Uranium Metallogenic Condition of the Upper Cretaceous Yaojia Formation and Qingshankou Formation in Kailu Depression of Songliao Basin
摘要
Abstract
The uranium host layers in the southern part of Songliao Basin are mainly the Upper Cretaceous Yaojia Formation and Qingshankou Formation,both of which are red variegated and difficult to discriminate in the region.The unclear sequence framework restricts the expansion of exploration achievements.This paper conducted a comparative study on Yaojia Formation and Qingshankou Formation through core observation,seismic interface tracking,well logging,facies identification biological fossil assemblages,geochemical and heavy mineral analysis indicators,and preliminarily identified the stratigraphic division indicators of Yaojia Formation and Qingshankou Formation.The results show that the top of Qingshankou Formation is dominated by purple-red mudstone,and the lower part is purple-red,gray fine sandstone,argillaceous medium-coarse sandstone and thin-bedded purple-red mudstone.The seismic facies of Qingshankou Formation are characterized by poor continuity of reflection waves,small or medium amplitude,and the well logging curves are bell,finger,and box-shaped.CIA average is 57.16.And the petrochemical and heavy minerals are mainly ilmenite+garnet+barite+zircon.Yaojia Formation can be divided into two members,the lower member is dominated by brownish-red,brick-red,gray fine sandstone,medium sandstone and sandy conglomerate,and the upper member is composed of a set of gray-green,purple-red mudstone and gray-white siltstone,fine sandstone and medium sandstone.The seismic facies of Yaojia Formation are characterized by continuous reflection waves,high or high amplitude,low amplitude,and continuous reflection at the bottom,and the well logging curves are box,bell-shaped,and a small amount of finger-shaped,CIA average is 65.22,and the petrochemical and heavy minerals are the combination of weathering CIA mutation at the bottom,zircon+garnet+albite+anatase+ilmenite.On this basis,the uranium metallogenic conditions of Yaojia Formation and Qingshankou Formation are systematically analyzed and compared.The study shows that both have sufficient uranium source,which are mainly from the Middle and Cenozoic volcanic rocks and Hercynian and Yanshan granites in the southern margin of Songliao Basin.During Qingshankou-Yaojia period,the channel developed from south-west to north-east,and a typical sedimentary environment of alluvial fan-braided river-meandering river-delta-lake was formed from upstream to downstream.The ore-bearing gray sand bodies of Qingshankou Formation and Yaojia Formation are rich in reductant such as organic matter,carbonized plant detritum,pyrite,etc.,and their organic carbon content is 0.11%～0.56%,indicating that they all have good reducing properties.The oxidation zone of Yaojia Formation is mainly distributed in a planar manner.The mineralization potential of Yuliangbao-Qianjiadian and Jiamatu-Baokang is huge.The oxide zone of Qingshankou Formation is distributed in the form of a ring belt,and the mineralization potential of the Naiman,Tongliao-Qianjiadian and other sections is greater.关键词
松辽盆地/姚家组/青山口组/地层特征/铀成矿条件Key words
Songliao Basin/Yaojia Formation/Qingshankou Formation/stratigraphic characteristics/uranium mineralization conditions分类
天文与地球科学引用本文复制引用
王之晟,卢天军,郭恒飞,陈旭,贾立城,宁君..松辽盆地开鲁坳陷上白垩统姚家组与青山口组地层发育特征及铀成矿条件[J].铀矿地质,2024,40(4):619-632,14.基金项目
中核集团集中研发项目"砂岩型铀矿多重耦合地质成矿作用与时空定位"(编号:中核科发2021-143)和中国核工业地质局地勘费项目"松辽盆地通辽-大庆地区铀资源调查评价与勘查"(编号:202212)联合资助. （编号:中核科发2021-143）
