摘要
为研究砂岩型铀矿与古层间氧化带之间的关系,本文通过对鄂尔多斯盆地苏台庙地区直罗组下段上亚段砂岩的地球化学环境和常量元素进行规律总结与讨论。将古层间氧化带进一步细分为古氧化残留带、二次还原带、叠置带和原生带等4个亚带,总结了各亚带地球化学环境指标特征,揭示了各亚带常量元素的演化规律,其中Si、Al、Fe和Ca活动性较强,Na、Mg和Ti活动性其次,而K、Mn和P较稳定。研究认为,该地区砂岩依次经历了成岩作用、古氧化作用、主成矿期铀成矿作用、二次还原作用和叠加铀成矿作用等,且未曾经历大幅沉降和显著构造热事件。研究区铀成矿作用与还原介质和Ca含量关系最密切,其次是Si、Fe、Ti,铀矿勘查应以叠置亚带为重点,兼顾二次还原亚带。
This paper focuses on the relationship between sandstone type uranium and paleo interlayer oxidation zones.We examine the geochemical environment and major elements of sandstone in the upper sub-member of the lower member of Zhiluo Formation in the Sutaimiao area of Ordos Basin.The paleo interlayer oxidation zone is further subdivided into four subzones:paleo oxidation residual zone,secondary reduction zone,superimposed zone and primary zone.The geochemical environment index characteristics of each subzone are summarized,and the evolution law of major elements in each subzone is revealed.Research suggests that the activity of Si,Al,Fe and Ca is stronger,Na,Mg and Ti are the second,while K,Mn and P are relatively stable.It is considered that the sandstone has experienced diagenesis,paleo oxidation,and uranium mineralization in the main metallogenic period,secondary reduction and superimposed uranium mineralization in turn,and has not experienced large-amplitude subsidence and significant tectonic thermal events.Uranium mineralization in the study area is closely related to reduction media and Ca content,followed by Si,Fe,and Ti.Uranium exploration should focus on the superimposed subzone and give consideration to the secondary reduction subzone.
作者
涂颖
蒋孝君
任志勇
秦培鹿
TU Ying;JIANG Xiaojun;REN Zhiyong;QIN Peilu(Geological Survey No.208,China National Nuclear Corporation,Baotou,Inner Mongolia 014000)
出处
《地质与勘探》
CAS
CSCD
北大核心
2022年第1期61-72,共12页
Geology and Exploration
基金
中国核工业地质局项目(编号:201902-4、201812-1)资助。
