摘要
通过对江西赣县峰山重稀土矿床的地质和地球化学特征进行研究,进一步探讨重稀土元素的富集规律及地质意义。赣县峰山花岗岩体风化壳离子吸附型高钇低铕型重稀土矿床位于大埠岩体西部,是大埠花岗岩体高度分异演化的产物,成矿母岩以黑云母二长花岗岩为主。地球化学特征显示:花岗岩SiO2含量较高(70.42%~75.85%),Al2O3>(CaO+K2O+Na2O),属于铝过饱和系列岩石;CaO、MgO含量偏低,属于高硅、富碱、贫钙镁过铝质高分异花岗岩。花岗岩ΣCe/ΣY平均值为0.90,属于重稀土富集型。Eu呈明显负异常,多数样品Ce呈弱负异常,表明稀土元素发生了不同程度的分异和富集,成岩作用和风化作用共同导致了微量元素和稀土元素发生不同程度的分异和富集。
By studying the geological and geochemical characteristics of Fengshan heavy rare earth element(HREE)deposit in Ganxian of Jiangxi Province,the paper further discusses the enrichment rule and geological implication of HREEs.The ion-adsorption high Y low Eu HREE deposit of Fengshan granite weathering crust is located in the west of Dabu rock mass,with biotite monzogranite as the main metallogenic parent rock.The geochemical characteristics show that the SiO2 content(70.42%~75.85%)in granite is high,Al2O3>(CaO+K2O+Na2O),belonging to the aluminum supersaturation series,with low CaO and MgO content,belonging to high silicon,rich alkali,poor calcium-magnesium peraluminous highly differentiated granite.The averageΣCe/ΣY of granite is 0.90,belonging to HREE enrichment type.The obvious negative Eu anomaly,and weak negative Ce anomaly in most samples show different degrees of differentiation and enrichment of REEs,which are caused by both the diagenesis and weathering process.
作者
张青
陈斌锋
张兴文
ZHANG Qing;CHEN Bin-feng;ZHANG Xing-wen(Gannan Geological Survey Party, Bureau of Geology and Exploration and Development of Mineral Researches of Jiangxi Province, Ganzhou 341000, China)
出处
《华东地质》
2020年第4期359-367,共9页
East China Geology
基金
江西省地质勘查基金管理中心“江西省赣县—定南县稀土矿调查评价(编号:20090211)”
国土资源部、工业与信息化部、财政部“赣州市稀土资源远景评价(编号:财建[2013]559号、赣财建[2013]121号)”项目联合资助。
关键词
离子吸附型重稀土矿床
重稀土元素
高分异花岗岩
地球化学特征
ion-adsorption HREE deposit
heavy rare earth element
highly differentiated granite
geochemical characteristics
