德兴铜厂斑岩铜矿成矿流体演化特征  

Evolution of Ore-forming Fluids in the Tongchang Porphyry Copper Deposit, Dexing,Northeast Jiangxi Province

作　　者：姚静[1,2] 倪培[2] 赵葵东[2] 王洪涛[1] 

机构地区：[1]南京大学表生地球化学研究所,地球科学与工程学院,南京210093 [2]南京大学内生金属矿床成矿机制研究国家重点实验室,地质流体研究所,地球科学与工程学院,南京210093

出　　处：《矿物岩石地球化学通报》2012年第2期97-104,共8页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：全国危机矿山接替资源找矿成矿规律总结项目(20089935)

摘　　要：为探讨成矿流体的特征和演化过程,对德兴铜厂斑岩铜矿床不同蚀变-矿化带石英细脉中的流体包裹体进行详细的岩相学观察、显微测温、显微激光喇曼探针工作。结果显示,德兴铜厂斑岩铜矿主要有三类流体包裹体:富液相包裹体(Ⅰ型),富气相包裹体(Ⅱ型)、多相包裹体(Ⅲ型);成矿早期的Ⅰ型包裹体,主成矿期的Ⅱ型和III型包裹体,以及成矿晚期的I型包裹体的平均均一温度和平均盐度分别为:481℃,8.1%;410℃,1.2%;389℃,56%和215℃,3.1%;主成矿期的II型和III型包裹体的平均均一温度相近,但盐度相差很大,指示了沸腾作用的发生;从早期到晚期,成矿流体呈现温度降低,挥发分逸出的趋势。This paper discusses the characteristics and the evolution of the ore-forming fluids in the Tongchang porphyry copper deposit of Dexing on the basis of the analyses of petrography,microthermometry and raman on fluid inclusions in the quartz veins of different alteration-mineralizaiton belts.The results show that： There are three types fluid inclusions： Liquid（H2O）-rich fluid inclusions（I）,gas-rich fluid inclusions（II）,multiphasic fluid inclusions（III）.The homogenization temperature and salinity of the I type fluid inclusion in the early stage is 481℃ and 8.1%,respectively;the homogenization temperatures and salinities of II,III types fluid inclusions in the ore-forming stage are 410℃,389℃ and 1.2%,56%,respectively;the homogenization temperature and salinity of the I type fluid inclusion in the late stage is 215℃and 3.1%,respectively.Fluid inclusions of II and III types have similar homogenization temperature and very different salinity,which implies that the ore-forming fluids have been boiled in this stage.When boiling,CO2 and water are immiscible,most CO2 get into the II type inclusions.Boiling and immiscibility of fluid are very important for the mineralization;from the early stage to the late stage,the temperature and the content of CO2 of the ore-forming fluids decreased.

关 键 词：流体包裹体 石英细脉 成矿流体 斑岩铜矿 德兴 

分 类 号：P618.41[天文地球—矿床学]