福建李坊重晶石矿床硅质岩地球化学特征及其构造背景  

Geochemical characteristics of the siliceous rocks in the Lifang barite deposit, Fujian Province, and its implications for tectonic settings

作　　者：罗坤 黎敦朋[1] 肖爱芳[1] 孔令添 LUO Kun;LI Dun-peng;XIAO Ai-fang;KONG Ling-tian(Zijin Mining College,Fuzhou University,Fuzhou 351018,China)

机构地区：[1]福州大学紫金矿业学院

出　　处：《华东地质》2019年第3期216-225,共10页East China Geology

基　　金：福建省自然科学基金“闽西南寒武纪中低温热水沉积作用与成矿效应研究:以李坊特大型重晶石为例(编号:2017J01467)”项目资助

摘　　要：为研究福建李坊重晶石矿床硅质岩的成因和构造背景,对该矿床9件硅质岩样品进行了主量元素、稀土元素和微量元素地球化学分析。结果显示:重晶石化硅质岩富Al、Ti、Fe、Mn和Mg,顶板硅质岩富Al、Fe,贫Mn、Ti、Mg;重晶石化硅质岩和顶板硅质岩稀土元素含量均较低,且富集轻稀土元素,Eu呈弱负异常-正异常,Ce呈负异常-弱正异常;Ba、Sr、Rb和Th相对富集,Ta、Hf和Y相对亏损。李坊重晶石矿床中硅质岩为热水沉积成因,硅质岩在沉积过程中受陆源物质输入影响,形成于酸性氧化的大陆边缘构造环境。In order to understand the genesis and tectonic settings of the Lifang barite deposit,this study carried out major elements,rare earth elements and trace elements analysis for nine siliceous rocks samples from the deposit.The results show that baritized siliceous rocks are rich in Al,Ti,Fe,Mn,Mg,and roof siliceous rocks are rich in Al,Fe and poor in Mn,Ti and Mg.Both siliceous rocks are characterzied by relatively lowΣREEs(but rich LREEs),weak negative to positive Eu anomalies and negative to weak positive Ce anomalies,and enrichment of Ba,Sr,Rb and Th,and depletion of Ta,Hf and Y.The siliceous rocks in the Lifang barite deposit was hydrothermal in origin,and deposited in the tectonic settings of continental margin and affected by addition of continental material during sedimentation.

关 键 词：硅质岩 地球化学特征 重晶石矿床 热水沉积 构造背景 福建李坊 

分 类 号：P578.71[天文地球—矿物学]