世界核地质科学2025，Vol.42Issue(5)：929-942,14.DOI:10.3969/j.issn.1672-0636.2025.05.003
银额盆地西部中-新生代沉积古环境和古气候特征及其对砂岩型铀矿成矿的影响
Characteristics of Mesozoic-Cenozoic sedimentary paleoenvironment and paleoclimate and their constraints on sandstone-type uranium mineralization in the western Yingen-Ejin basin
摘要
Abstract
In recent years,the Mesozoic-Cenozoic strata in the western Yingen-Ejin basin have shown high potential for sandstone-hosted uranium mineralization.However,the sedimentary environment and paleoclimatic characteristics remain poorly understood,which hinders a comprehensive understanding of the uranium mineralization mechanisms.This study focused on the Mesozoic-Cenozoic strata in the Juyanhai depression of the western Yingen-Ejin basin.Detailed geochemical analysis were conducted to quantitatively reconstruct the evolution of the paleosedimentary environment and paleoclimate in the study area.The results indicated that from the Early Cretaceous to the Neogene,the study area was generally characterized by an oxidative sedimentary background,with locally weak reducing conditions.The paleosalinity evolved from freshwater-brackish to brackish-saline,with the Suhongtu and Sikouzi formations exhibiting relatively high salinity.The paleoclimate was generally warm and humid to semi-humid/semi-arid,with the Bayingebi formation experiencing a humid climate and the Suhongtu formation showing significant alternations between dry and wet conditions.These environmental characteristics collectively controlled the migration,enrichment,and precipitation of uranium:oxidative conditions promoted uranium activation and migration,while local reducing environments facilitated uranium precipitation;moderate salinity enhanced the complexation and migration capacity of uranium;and climatic fluctuations drove fluid circulation and uranium source supply.Overall,the Suhongtu formation was considered to have the highest potential for uranium mineralization.This study provides a scientific basis for sandstone-type uranium exploration in the western Yingen-Ejin basin.关键词
银额盆地/中-新生界/沉积环境/古气候/砂岩型铀矿Key words
Yingen-Ejin basin/Mesozoic-Cenozoic strata/paleoenvironment/paleoclimate sandstone-type uranium mineralization分类
天文与地球科学引用本文复制引用
杨喆,刘武生,牛霆,贾立城,李伟涛,纪宏伟..银额盆地西部中-新生代沉积古环境和古气候特征及其对砂岩型铀矿成矿的影响[J].世界核地质科学,2025,42(5):929-942,14.基金项目
核技术研发项目(编号:地H2401)资助 Supported by Nuclear Technology R&D Program(No.地H2401). （编号:地H2401）
