松辽盆地南部陆家堡凹陷四方台组沉积特征及铀成矿条件分析  

Sedimentary Characteristics and Uranium Metallogenic Condition of Sifangtai Formation in Lujiapu Depression,Southern Songliao Basin

作　　者：佟术敏 TONG Shumin(Geologic Party No.243,CNNC,Chifeng,Inner Mongolia 024006,China)

机构地区：[1]核工业二四三大队,内蒙古赤峰024006

出　　处：《铀矿地质》2025年第2期197-214,共18页Uranium Geology

基　　金：中国核工业地质局项目“松辽盆地通辽-大安地区铀矿资源调查评价与勘查”(编号:202210)和“内蒙古奈曼旗八仙筒-开鲁县建华地区铀矿资源调查评价”(编号:202210-2)联合资助。

摘　　要：松辽盆地南部陆家堡凹陷四方台组砂岩型铀矿勘查程度低,铀成矿潜力不明。文章通过对陆家堡凹陷铀矿带特征、岩心镜下观察、砂岩粒度分析、钻孔岩性-测孔相特征、沉积相在垂向和平面的分布特征等方面进行系统研究分析,认为四方台组砂岩类型主要为长石质岩屑砂岩和长石砂岩,沉积相类型为冲积扇相,基本覆盖整个研究区,包括扇根、扇中及扇端亚相,并进一步识别出9种沉积微相。文章从赋矿砂体微观矿物对铀成矿的制约、垂向和平面沉积相对铀矿带的控制及砂体、含砂率的空间耦合关系对成矿的影响3个方面,归纳总结了铀成矿的规律和制约因素,最终在绍根地区、建华北西地区、开鲁西部和东部地区预测4片找矿远景区,为陆家堡凹陷乃至松辽盆地铀矿找矿工作提供重要的指示作用。Due to the low exploration level of Sifangtai Formation in the Lujiabu depression,the potential for sandstonetype uranium deposit is still undetermined.Through a comprehensive study and analysis of the characteristics of the uranium deposit belt in Lujiabu depression,the microscopic observation of rock cores,the analysis of grain size of sandstone,the characteristics of lithology-logging facies and the distribution of sedimentary facies in the vertical and horizontal directions,it was concluded that Sifangtai Formation sandstone type was predominantly quartzose feldspathic sandstone and quartz sandstone.The primary sedimentary facies was alluvial fan,which extended across the entire study area and encompassed sub-facies corresponding to the fan root,middle section,and terminus.Furthermore,nine distinct microfacies were identified.This paper elucidated the pattern and constraining factors of uranium mineralization from three perspectives:The microscopic mineral constraints on uranium mineralization within uranium-bearing sand bodies;The influence of sedimentary facies on the vertical and horizontal distribution of uranium mineralization belts;The spatial coupling relationship between sand bodies and sand content in relation to uranium mineralization.Finally,four prospective exploration areas had been identified:the Jiaogeng area,the northwestern sector of Jianhua,and both the western and eastern sectors of Kailu,which is of significant reference for uranium exploration activities in the Lujiabu depression and the Songliao Basin.

关 键 词：四方台组 沉积特征 砂岩型铀成矿 成矿预测 陆家堡凹陷 

分 类 号：P619.14[天文地球—矿床学]