摘要
大富岭铀矿床隶属于湘东明月峰矿田,为该矿集区新探明的花岗岩外带型铀矿床。近年来找矿勘探的实践表明,该矿床具有较大的铀矿化规模和找矿前景。然而,由于对该矿床铀矿物特征的分析及其铀成矿时代约束较为薄弱,在一定程度上制约了对矿床成因的理解。鉴于此,本文在详细的野外地质调查基础上,采集了典型的铀矿石样品,通过室内岩矿鉴定、扫描电镜、电子探针和LA-ICP-MS等测试方法,首次解译了该矿床铀矿物特征及其成矿时代。结果表明,该矿床出露铀矿物主要为沥青铀矿,铀成矿年龄约为70 Ma,成矿时代属白垩纪晚期。结合大地构造背景,初步认为其成矿作用与华南中生代(75~70 Ma)岩石圈伸展减薄事件密切相关,间接指示大富岭铀矿床可能形成于岩石圈伸展减薄的构造动力学背景。
The Dafuling Uranium Deposit is part of the Mingyuefeng Ore Field in eastern Hunan,and it represents a newly proven perigranitic uranium deposit within this ore concentration area.Recent prospecting and exploration practices have shown that the deposit exhibits significant uranium mineralization scale and considerable prospecting potential.However,due to the insufficient analysis of the characteristics of uranium minerals in this deposit and the weak constraints on the timing of uranium mineralization,the understanding of the ore deposit’s genesis has been somewhat hindered.Against this backdrop,this study conducted detailed field geological surveys,collected representative uranium ore samples,and employed laboratory ore-mineral identification,scanning electron microscopy(SEM),electron probe microanalysis(EPMA),and LA-ICP-MS,among other analytical techniques.For the first time,it deciphered the characteristics of uranium minerals in the deposit and constrained their metallogenic age.The results indicate that the exposed uranium mineral in the deposit is mainly uraninite,with a uranium metallogenic age of approximately 70 Ma,corresponding to the late Cretaceous.Combined with the tectonic setting,it is preliminarily considered that the mineralization is closely related to the Mesozoic(75-70 Ma)lithospheric extension and thinning event in South China,indirectly indicating that the Dafuling Uranium Deposit might have formed in a tectonodynamic setting of lithospheric extension and thinning.
作者
范鹏飞
申锡坤
黄广文
李满根
谷勇
王珂
刘涛
郭业达
FAN Pengfei;SHEN Xikun;HUANG Guangwen;LI Mangen;GU Yong;WANG Ke;LIU Tao;GUO Yeda(Yichun University,Yichun,Jiangxi 336000,China;East China University of Technology,Nanchang,Jiangxi 330013,China;Hunan Engineering Technology Research Center for Evaluation and Comprehensive Utilization of Associated Radioactive Mineral Resources,Changsha,Hunan 410007,China;Hunan Branch of China National Geological Exploration Center of Building Materials Industry,Zhuzhou,Hunan 412001,China;School of Emergency and Disaster Reduction,Qinghai Normal University,Xining,Qinghai 810008,China)
出处
《现代地质》
北大核心
2025年第4期920-930,共11页
Geoscience
基金
中国核工业地质局基金项目(202124-1,202324-3)。
