华南地质2026，Vol.42Issue(4)：664-680,17.DOI:10.3969/j.issn.2097-0013.2026.04.008
内蒙古二连盆地哈达图铀矿床赛汉组上段沉积控矿机理及其勘探意义
Sedimentary Controls on Uranium Mineralization and Their Exploration Significance in the Upper Member of the Saihan Formation,Hadatu Uranium Deposit,Erlian Basin,Inner Mongolia
摘要
Abstract
[Objective]The upper member of the Saihan Formation in the Hadatu area of the Erlian Basin is an important ore-hosting horizon for sandstone-hosted uranium deposits.This study investigates the sedimentary facies characteristics of this formation and their relationship with uranium mineralization,aiming to clarify the ore-forming mechanism of the Hadatu uranium deposit and to provide guidance for subsequent uranium exploration in the area.Therefore,it is necessary to define the sedimentary system of the upper member of the Saihan Formation and further discuss its control on uranium mineralization.[Methods]Taking drill cores from the ore-hosting strata in the Hadatu area as the main research object,this study,based on field geological investigation and core logging,established detailed single-well sedimentary columns and inter-well correlation profiles.Comparative analysis was then carried out to discuss the relationships among sedimentary facies types,sandbody architecture,and uranium mineralization in the study area.[Results]The upper member of the Saihan Formation is generally characterized by fluvial deposits,dominated by a braided river system.Several microfacies are developed,including braided channels,mid-channel bars,abandoned channels,and floodplains.Composite channel sand bodies are the most developed,showing large thickness,good lateral connectivity,and multi-stage channel superimposition.Uranium mineralization is mainly controlled by the combined effects of sedimentary facies distribution,sandbody architecture,and redox zonation.Oxygenated uranium-bearing fluids mainly migrated along the main channels from southwest to northeast,with local diffusion from the main channels toward both sides.When the fluids entered abandoned channels and sand-mud transition zones,oxygen was gradually consumed,leading to the formation of redox interfaces,where uranium was reduced from U6+to U4+and subsequently precipitated and enriched.[Conclusions]This study establishes a metallogenic model for the Hadatu uranium deposit,which provides a basis for prospecting prediction of similar sandstone-hosted uranium deposits in the study area and adjacent regions.关键词
哈达图铀矿床/赛汉组上段/沉积相/氧化还原界面/成矿作用/二连盆地Key words
Hadatu uranium deposit/upper member of the Saihan Formation/sedimentary facies/redox interface/mineralization/Erlian Basin分类
天文与地球科学引用本文复制引用
田润宇,聂逢君,吕永华,彭瑞强,张鑫..内蒙古二连盆地哈达图铀矿床赛汉组上段沉积控矿机理及其勘探意义[J].华南地质,2026,42(4):664-680,17.基金项目
国家自然科学基金项目(U2244205) （U2244205）
