【作者】 王彦博；

【导师】 顾雪祥；

【作者基本信息】 中国地质大学(北京) ， 矿产普查与勘探， 2012， 硕士

【摘要】 湖北铜绿山铜铁矿床处于长江中下游铁铜成矿带西部鄂东成矿区内，是鄂东南地区典型的矽卡岩型铜铁矿床。矿体呈透镜状产于下三叠统大冶群第三至第七岩性段大理岩与铜绿山岩体的接触带。本文通过对铜绿山矿床硫、氢、氧、碳、铅同位素地球化学及稀土、微量元素地球化学研究，探讨了成矿热液中水、碳、硫、铅的来源以及成矿热液的演化，为了解热液和成矿物质来源进而为研究矿床成因提供依据。研究表明铜绿山石英二长闪长（玢）岩具有高硅、低镁、富碱（以钠为主）的特征。稀土配分曲线呈右倾斜型，即轻稀土富集，重稀土相对亏损。岩体富集大离子亲石元素Rb、Ba、Th、U、K、Sr，强烈亏损高场强元素Nb、Ta、Ti。矿床岩浆岩、矽卡岩、矿石、稀土元素配分曲线存在一定的相似性，均富集轻稀土，轻稀土部分较陡，重稀土部分趋于平缓，显示了铜绿山矿床与岩浆岩的密切联系。矿床成矿早期阶段流体主要来源于岩浆，后期大气降水比重加大；热液中的碳主要为深源岩浆来源，少量来自海相碳酸盐岩的溶解作用；矿石中硫化物的硫同位素组成特征反应了硫来自深源岩浆；矿石铅同位素组成稳定，为正常铅，主要来源于上侵过程中受地壳物质混染的幔源岩浆。通过LA-ICP-MS测得的铜绿山石英二长闪长玢岩的U-Th-Pb同位素等时线年龄为141±1.1Ma，与前人测得的矿床的成矿年龄137～140Ma，在误差范围内基本一致，存在较短的成岩成矿时差。铜绿山矿床与铜绿山岩体在时间、空间和成因上具有密切的联系。更多还原

【Abstract】 Located in the southeastern Hubei metallographic province of the Middle-LowerYangtze River Fe-Cu metallogenic belt,the Tonglushan Cu-Fe deposit is a typicalskarn Cu-Fe deposit in the southeastern Hubei province. The ore bodies,in thelenticular forms, occur in the contact zone between the marble of4th-7th M embersof the Lower Triassic Daye Group. This paper mainly studied S,H,O,C,Pb isotopiccompositions, geochemistry of rare earth elements and trace elements, analyzed theindicative meaning of these isotopes to the ore fluids and the sources of theore-forming materials and intrusions to to provide basis for study of deposit genesis.The results show that Tonglushan rock body has the characteristics of highsilicon, low magnesium, rich alkali (mainly sodium). The REE distribution curves areof right inclination which indicates they are relative enrichment of LREE, relativedepletion of HREE. The rocks are highly enriched in the large ion lithophile elements(LILE) such as Rb, Ba, Th, U, K, Sr but strongly depleted in the high field strengthelements(HFSE)such as Nb,Ta and Ti.The magmatic rock,skarn,ore have similar REE distribution curves that they areall relative enrichment of LREE and the LREE part of the curves is steeper，whilethe HREE part is flatter shows that deposit has a close relation with the magma.Ore fluids were most likely composed of magmatic water at the earlyore-forming stage and mixed with much meteoric water at the late ore-forming stage;Sulfur and carbon isotopic data suggest that the ore forming materials were mainlyderived from the deep magma and the carbon derived subordinately from thedissolution of wall rocks or the mantle. The Pb isotopic composition of ore sulfidesare stable and they are ordinary common lead. Ore lead derived from mantle magmawhich was subjected to the hybridization of crust materials in the course of intrudedupward.The U-Th-Pb harmonic age of the rock body is141±1.1Ma,measured byLA-ICP-MS.The data indicate that the age of Tonglushan rock body are almostidentical to the mineralization age （137～140Ma） from previous researches. Tonglushan deposit has a close relation with the rock body in space time and genesis.更多还原