紫金山铜金矿明矾石交代蚀变岩的岩石地球化学特征  

Lithogeochemical Characteristics of the Alunite Metasomatic Alterated Rock of the Zijinshan Gold-Copper Deposit

作　　者：王翠芝[1] 

机构地区：[1]福州大学紫金矿业学院,福建福州350108

出　　处：《地球科学进展》2013年第8期897-912,共16页Advances in Earth Science

基　　金：国家自然科学基金项目"紫金山铜金矿硫酸盐对成矿的指示作用"(编号:41072067);国家科技支撑计划项目"浅成热液-斑岩型铜;金矿深部成矿模式与勘查技术示范研究"(编号:2009BAB43B04)资助

摘　　要：在野外地质调查和岩(矿)相学的基础上,通过对比分析紫金山铜金矿各种交代蚀变岩的岩石地球化学特征,对本矿高硫化型浅成低温热液成矿体系有了进一步认识。相比其他种类的交代蚀变岩,明矾石交代蚀变岩的岩石地球化学特征主要表现为:①主量元素中Al2O3,K2O明显增加,而SiO2明显降低,其他造岩元素也都有降低的趋势;②成矿元素Cu与运矿元素S,F相关性密切;Cu与Au,Ag等成矿元素呈一定的正相关性,而与Pb,Zn,Sn等矿化相关性较差;③微量元素均显示出大离子亲石元素较高,明显富集Rb,Ba,Tb,U,Pb,而低P,Ti;④稀土元素普遍具有较高的轻稀土、较低的重稀土,负Eu异常较小或不明显。明矾石交代蚀变岩的这些岩石地球化学特征显示出紫金山铜金矿高硫化型浅成低温热液是富含Cu,Au,Ag等多种成矿元素和S,F等运矿元素的成矿流体,其形成是与燕山晚期中酸性的火山—侵入杂岩有关的岩浆热液与燕山早期的花岗岩类长期广泛水—岩反应的结果。On the basis of geological survey and petrographic （ore microscopy） and through the comparison and analysis of geochemical characteristics of the metasomatic aherated rocks of the Zijinshan gold-copper deposit, we have turther understanding on the high sulfidation epithermal hydrothermal metallogenic system of the Zijinshan gold-copper deposit. Compared with other kinds of mctasomatic alterated rocks, geochemical characteristics of alunite metasomatic alterated rock are mainly reflected in： （1）Al2O3 and K2O in the main elements increase significantly, and SiO2 reduces significantly, and the other rock-forming elements also have a reduced trend; （2）The analysis of the metallogenic elements shows that there is a close correlation between copper, sulfur and fluorine. The metalh〉genic element has a weak positive correlation with Au and Ag, and has poor correlation with Pb, Zn, Sn, etc. ; （3）Trace elements show the contents of large ion lithophile elements are higher in the fluid, which is significantly rich in Rb, Ba, Th, U and Pb significantly and poor in P, Ti; （4）Rare earth elements generally have high light rare earths, low heavy rare earths and a slight negative gu anomaly or without obvious negative Eu anomaly. Geochemical characteristics of alunite metasomatic alterated rock show that the high sulfidation epithermal hydrothermal oretorming solution of the Zijinshan gold-copper deposit is a kind of fluids rich in multiple ore elements of copper, gold, silver, etc. , and ore-forming elements of sulfur, fluorine, etc. , which formed from the long-term water-rock interaction of the magmatic hydrothermal solution related to the intermediate-acid volcanic-ntrusive complex of late Yanshan period and the granitoids of early Yanshan Period.

关 键 词：紫金山铜金矿 明矾石化 明矾石交代蚀变岩 岩石地球化学 指示作用 

分 类 号：P614[天文地球—矿床学]