河南桐柏地区铜锌多金属矿床的微量元素和稀土元素特征及成因意义  

Trace element and REE geochemistry and its metallogenic significance for Cu-Zn deposits in the Tongbai area,Henan

作　　者：李立兴[1] 李厚民[1] 王登红[1] 张长青[1] 

机构地区：[1]中国地质科学院矿产资源研究所,国土资源部成矿作用与资源评价重点实验室,北京100037

出　　处：《地学前缘》2009年第6期325-336,共12页Earth Science Frontiers

基　　金：国家自然科学基金项目"滇东北峨眉山玄武岩铜矿中有机质对铜富集成矿的作用"(40572060);中国地质调查局地质大调查项目"我国西部重要成矿区带矿产资源潜力评估"(1212010535804);中国地质调查局地质大调查项目"中国成矿体系综合研究"(1212010634002);中国地质调查局地质大调查项目"我国重要矿产和区域成矿规律研究"(1212010633903)

摘　　要：为了探讨河南桐柏地区铜锌多金属矿的成因,采用ICPMS对刘山岩铜锌矿床、大栗树-方老庄铜锌矿床、羊圈铜矿化点的矿石和矿化岩石的微量元素和稀土元素进行测试。根据研究区铜锌矿石的微量元素和稀土元素特征将其分为4种类型:第一类REE配分曲线右倾,Eu异常不明显,Ce弱负异常,HFSE相对MORB弱亏损,Zr、Ti弱负异常;第二类REE配分曲线右倾,Eu负异常,Ce弱负异常;第三类REE配分曲线右倾,Eu明显正异常,Ce负异常,HFSE相对MORB强烈亏损,Zr、Ti强负异常;第四类REE配分曲线平坦,Eu明显正异常,Ce弱负异常,HFSE相对MORB亏损,无Zr、Ti异常。研究表明:桐柏地区铜锌多金属矿床为海底火山成因块状硫化物矿床,矿石和矿化岩石与矿区火山岩的微量元素和稀土元素地球化学特征相似,第一类与矿区基性火山岩类似,第二类与矿区酸性火山岩类似,第三类指示高温热液流体与海水发生了对流混合且残留相有较多难溶矿物,第四类指示源区为亏损地幔。这些特征表明成岩与成矿的物质来源具有一致性,同为经历早期多次熔融事件的地幔源区的部分熔融的产物。There are some Cu-Zn poly-metallic ore deposits of volcanic hosted massive sulfide（VHMS）type located in the Tongbai Region,Henan Province,China.The trace element and rare earth element（REEs）abundance of ores of Liushanyan Cu-Zn deposit,Dalishu-Fanglaozhuang Cu-Zn deposit and Yangjuan Cu-mineralizing spot were analyzed by using ICPMS method in order to discuss the genesis of these deposits.Four types have been identified on the basis of study on trace elements and REEs geochemistry：ores of the first type show LREE-enriched REE patterns,without Eu anomalies and weak negative Ce anomalies,but with a weak depleted HFSE and smaller anomalies at Zr and Ti relative to N-MORB;ores of the second type show LREE-enriched REE patterns having negative Eu anomalies and weak negative Ce anomalies;ores of the third type show LREE-enriched REE patterns,having positive Eu anomalies and negative Ce anomalies,with a depleted HFSE and small negative anomalies at Zr and Ti relative to N-MORB;ores of the fourth type show horizontal REE distribution patterns,having positive Eu anomalies and weak negative Ce anomalies,with a depleted HFSE and no anomalies at Zr and Ti relative to N-MORB.The first type and the second type have similar characteristics to the basic volcanic rocks and acid volcanic rocks respectively.Characteristics of the third type indicate that the convective mixing of a small amount of sea water with high temperature hydrothermal fluids had happened with a lot of minerals which are insoluble in the solvents in the residual phase.The fourth type has a depleted mantle source.These characteristics indicate that the mineralization material has the same source with its wall rocks of the Liushanyan Formation,which are the products of mantle partial melting that had undergone multiple earlier melting events.

关 键 词：铜锌矿床 微量元素 稀土元素 刘山岩 桐柏 河南 

分 类 号：P618.6[天文地球—矿床学] P618.7[天文地球—地质学]