326铀矿床矿石成分、围岩蚀变及成因探讨

详细信息    查看官网全文

• 英文论文题名：Research on ore composition,wallrock alteration and genesis of 326 uranium deposit
• 论文作者：叶庆森
• 英文论文作者：YE Qing-sen ; Research Institute No.230 ; CNNC
• 年：2015
• 作者机构：核工业二三〇研究所;
• 论文关键词：326铀矿床 ; 矿石 ; 矿物成分 ; 围岩蚀变 ; 成因
• 英文论文关键词：326 uranium deposit ; ore ; mineral composition ; wallrock alteration feature ; genesis
• 会议召开时间：2015-09-21
• 会议录名称：中国核科学技术进展报告（第四卷）——中国核学会2015年学术年会论文集第1册（铀矿地质分卷、铀矿冶分卷）
• 语种：中文
• 分类号：P619.14
• 学会代码：EGVD
• 会议名称：中国核学会2015年学术年会
• 会议地点：中国四川绵阳
• 主办单位：中国核学会
• 学会名称：中国核学会
• 页数：6
• 文件大小：551k
• 原文格式：O
• 会议级别：全国

摘要

326铀矿床是我国重要的四大类型铀矿床之一花岗岩型铀矿床,位于南华活动带华夏褶皱带西侧。通过测定该矿床岩矿石矿物成分、研究围岩蚀变及其与铀矿化的关系,确认碱交代、赤铁矿化、绿泥石化、硅化和黏土化(高岭土化、伊利石化)与铀矿化关系密切。矿石中赋存的铀矿物主要有沥青铀矿、硅钙铀矿、硅铀矿、硅铅铀矿、铀黑、铜铀云母;伴生的金属矿物有闪锌矿、黄铁矿、白铁矿等,脉石矿物主要为石英、钾长石、斜长石、白云母、黑云母、白云石、方解石、磷灰石。在此基础上,探讨了该矿床成因机制:矿源岩为富铀黑云母二长花岗岩,岩浆、构造作用及围岩蚀变提供了热源并使铀活化、迁移、富集;由于成矿期围岩蚀变特别是碱交代和赤铁矿化,使储矿空间pH、Eh下降;同时,构造交汇开放空间发生减压降温作用,当富铀的氧化热液运移至该空间时使铀矿还原沉淀,从而形成铀矿床。
326 uranium deposit,which is a granite type uranium deposit,is located in the west side of Huaxia Fold Zone in Nanhua Mobile Zone,and is one of four important uranium deposit types in our country.Wallrock alteration and its relation to uranium mineralization are discussed on the basis of determination of mineral composition in rocks and ores,and analysis of geological and geochemical conditions.The results of determination and analysis of rocks and ores show that uranium minerals are mainly pitchblende,uranophane,soddyite,kasolite,uranium black,chalcolite;other metalliferous minerals are sphalerite,pyrite and marcasite,and gangue minerals are quarts,potassium feldspar,plagioclase,muscovite,biotite,dolomite,calcite and apatite in uranium ores,in which uranium content is between 0.05% and 0.34%.Alkalic metasomatism,hematitization,chloritization,silicification and clayization(e.g.,kaolinization) are main wallrock alterations relative to uranium mineralization Uranium metallogenic model of 326 deposit is approached:Uranium-rich biotitemonzonitic granite provided uranium source.Magmatism,tectonization and wallrock alterations provided heat sources,and remobiled,migrated and enriched uranium.The values of pH and Eh decreased in the space for uranium ore storage because of wallrock alterations such as alkalic metasomatism and hematitization during metallogenic stage.Uranium was reduced and precipitated,and then uranium ore-bodies formed because of decrease of P and T within the open space of tectonic intersection when uranium-rich hydrothermal solution of oxidation was migrated to the space.

引文

[1]杜乐天,王文广,刘正义.中国铀矿床研究评价(第一卷,花岗岩型铀矿床)[M].北京:中国核工业地质局,2011.
    [2]Ye Q S,Yamana S.Research on mineralogical and geochemical features and genesis of GX uranium deposit in China[R].TokyosPNC,1995.
    [3]中南306大队.中南铀矿床汇编[R].衡阳:中南306大队,1992.
    [4]核工业二三○研究所.鹿井地区碎裂蚀变花岗岩型铀矿资源的地质评估及寻找[R].长沙:核工业二三○研究所,1998.
    [5]Jones P M.Applied mineralogy-(a quantitative approach)[M],London:Graham&Trotman,1987.
    [6]Reed S J B.Electron microprode analysis[M].Cambridge:Cambridge University Press,1993.
    [7]Barnes H L.Geochemistry of hydrothermal ore deposits[M].New York:Wiley,1979:173-227.