江苏省海州式磷矿岩石地球化学特征及成矿背景  

Geochemical Characteristics and Metallogenic Setting of Haizhou-Type Phosphorite Deposit in Jiangsu Province

作　　者：李双喜 宋玉明 王肖 洪连明 王超 LI Shuangxi;SONG Yuming;WANG Xiao;HONG Lianming;WANG Chao(The 6 th Geological Institute of Jiangsu Province,Lianyungang,Jiangsu 222000;Chaohu Emergency ManagementBureau,Chaohu,Anhui 238006)

机构地区：[1]江苏省地质矿产局第六地质大队,江苏连云港222000 [2]巢湖市应急管理局,安徽巢湖238006

出　　处：《地质与勘探》2022年第6期1196-1208,共13页Geology and Exploration

基　　金：江苏省地质矿产勘查局科研项目“江苏省海州式磷矿成矿模式及找矿模型研究”(编号:2018KY06)资助。

摘　　要：本文对苏北地区锦屏组磷矿石及地层样品进行了岩相学及地球化学分析,研究了磷矿初始沉积环境和源区特征。磷矿类微量元素富集Ba、Pb、U、Sr,贫Th、Ta、Nb、Ti;REE配分曲线为LREE富集型,Ce负异常,表明成矿环境为陆缘海,且成矿过程受深海热水沉积和生物作用影响。Sr、Nd同位素初始值判断磷灰岩物质来源为年轻的地壳物质。绿片岩类微量元素富集Rb、Th、K,贫Th、U、Ta、Nb、Sr、Ti;REE配分曲线为LREE富集型,判断其原岩为陆源碎屑岩。(混合)片麻岩类微量元素富集Pb、Th、K,亏损Ba、Ta、Nb、Sr、Ti;REE配分曲线为LREE富集型,具地幔源区特征。The initial sedimentary environment and source characteristics of phosphorite deposition were studied by geochemical analysis of samples from the Jinping Formation in northern Jiangsu Province.The trace element characteristics of phosphorite deposit display enrichment of Ba,Pb,U,Sr,and depletion of Th,Ta,Nb and Ti;REE distribution pattern is rich in LREE,indicating that the metallogenic environment of phosphorite is characterized by hot water deposition and biological effects in continental margin sea.Initial values of Sr and Nd isotopes indicate that the source of phosphorite is young crustal material.The trace element characteristics of green schist show enrichment of Rb,Th,K,and depletion of Th,U,Ta,Nb,Sr,Ti;REE distribution pattern is rich in LREE,implying that the origin is terrigenous clastic sediment.The trace element characteristic of(migmatitic)gneiss shows enrichment of Pb,Th,K,relatively depletion of Ba,Ta,Nb,Sr,Ti;REE distribution pattern is rich in LREE,which shows characteristics of mantle source region.

关 键 词：“海州式”磷矿 苏北磷矿带 沉积变质磷矿 磷矿地球化学 

分 类 号：P629[天文地球—地质矿产勘探]