世界核地质科学2024，Vol.41Issue(6)：1089-1105,17.DOI:10.3969/j.issn.1672-0636.2024.06.003
鄂尔多斯盆地西南部下白垩统赋矿砂岩成矿流体特征及其地质意义
Characteristics and geological implications of ore-forming fluids of the Lower Cretaceous U-bearing sandstones in the southwestern Ordos basin
摘要
Abstract
Sandstone-type uranium deposit is currently the most significant mining type of uranium deposit in the world.In recent years,significant breakthroughs have been made in the exploration of sandstone-type uranium deposits in the Lower Cretaceous of the southwestern Ordos basin.New uranium mineralization has been discovered in the Lower Cretaceous Huanhe and Luohe formations in areas such as Zhenyuan,Xinzhuang and Pengyang.However,the evolution of ore-forming fluids and the metallogenic process are still unclear.To determine the characteristics and the evolution process of ore-forming fluids in the U-bearing sandstones,as well as to investigate their impact on the uranium mineralization process,studies were conducted in petrography,fluid inclusions,and geochemistry of typical samples from key regions.The research indicated that the U-bearing sandstones had undergone complex diagenetic processes,including limonitization,hematitization,early carbonatization,chloritization,sulfuration,and so on.Among these,sulfuration and the associated carbonate and barite filling were closely related to uranium mineralization.The ore-forming fluids were low in salinity and temperatures ranging from 130 to 180℃,which was higher than the maximum burial temperature of the Cretaceous strata.This may be due to the influence of early Cretaceous thermal events or fluids from deep sources.The ore-forming fluids were rich in organic matter and ore-forming elements such as U,Fe,Mo,Re,CuandZn,likely originating from the"Chang 7"hydrocarbon source rocks,consistent with the characteristics of"exhalative"uranium mineralization.关键词
成矿流体/成矿过程/下白垩统/砂岩型铀矿/鄂尔多斯盆地Key words
ore-forming fluids/metallogenic process/Lower Cretaceous/sandstone-type uranium deposit/Ordos basin分类
天文与地球科学引用本文复制引用
王婷婷,邱林飞,贺锋,武正乾,刘坤鹏,张良,韩美芝..鄂尔多斯盆地西南部下白垩统赋矿砂岩成矿流体特征及其地质意义[J].世界核地质科学,2024,41(6):1089-1105,17.基金项目
国家自然科学基金(编号:42302180)、中核集团青年英才项目(编号:地QNYC2402)和中核集团集中研发项目(编号:中核科发2021-143号)资助 Supported by National Natural Science Foundation of China(No.42302180),China National Nuclear Corporation Young Talent Project(No.地QNYC2402)and Centralized R & D Project of CNNC(No.中核科发2021-143号). （编号:42302180）
