江西德兴朱砂红斑岩铜矿流体包裹体特征及其成矿意义  

Fluid Inclusion Characteristic of the Zhushahong Porphyry Copper Deposit in Dexing, Jiangxi Province, and Its Metallogenic Significance

作　　者：吴德新[1] 赵元艺[2] 吕立娜[2] 许虹[1] 郭硕[1] 刘妍[2] 朱小云[3] 王增科[3] 水新芳[1] 

机构地区：[1]中国地质大学(北京),北京100083 [2]中国地质科学院矿产资源研究所国土资源部成矿作用与矿产资源评价重点实验室,北京100037 [3]江铜集团德兴铜矿,江西德兴334200

出　　处：《地质学报》2013年第5期677-690,共14页Acta Geologica Sinica

基　　金：国土资源部公益性行业科研专项(编号200911007-01;201111020-05;201311072);中国地质调查局地质矿产调查项目(编号1212011085408)资助的成果

摘　　要：朱砂红斑岩铜矿位于德兴斑岩铜矿矿集区的西北方向,紧邻铜厂铜矿。本文在前人有关德兴铜矿研究基础上,以铜矿流体包裹体为研究内容,通过野外详细的岩芯采样,室内石英斑晶、石英脉和方解石脉中包裹体测试及数据整理分析后初步发现:朱砂红斑岩铜矿流体包裹体大致可以分成五大类型(富液型包裹体、富气型包裹体、含CO2气液两相型包裹体、含子矿物多相型和固液两相型);相比铜厂整体成矿温度略低,盐度略高;由成矿流体压力47.27～184.47MPa,推导出成矿深度达2～4km,以及激光拉曼测试结果——流体中含有CO2、H2S和CH4等挥成份气体,它们可能与Au等元素的运移成矿有关。因此,从包裹体性质推测朱砂红铜矿不只是斑岩铜矿,可能是浅成热液斑岩型铜金矿床。此外,朱砂红矿区成矿流体来源至少有两种:高温岩浆流体和大气降水。伴随流体演化期次大致可以划分出3个成矿阶段:硅酸盐硫化物阶段、石英-硫化物阶段(即主成矿阶段,温度:200～340℃,盐度:2.0%～15%NaCl)、碳酸盐-硫酸盐硫化物阶段。同时,均一温度、盐度及压力等暗示在流体演化和成矿过程中岩浆流体发生过沸腾或不混溶作用。The Zhushahong porphyry copper deposit is located in northwest of the Dexing Ore-intensive area, and is close to the Tongchang copper deposit. Based on previous work, this paper focuses on fluid inclusions studies of the Zhushahong deposit. Through field sampling, optical observations, this study analyzed fluid inclusions from quartz phenocryst, quartz vein and calcite vein and testing data. The fluid inclusions in the deposit can be classified into five types： liquid~ vapor, liquid-rich inclusions; liquid＋ vapor, vapor-rich inclusions; CO2-bearing inclusions; halite-bearing multiphase inclusions; melt-bearing inclusions. Compare with the Tongchang copper deposit, this deposit has low metallogenic temperature but high salinity. Pressure of ore-forming fluid was 47.27～184.47 MPa, from which a metallogenic depth ranging from 2 to 4 km can be inferred. The result of Laser Raman spectroscopic analyses shows that ore forming fluids contain CO2, H2 S and CH4 gas, which may associate with the migration of element Au. It can be inferred from the characteristic of the fluid inclusions that the Zhushahong copper deposit is not only the porphyry copper deposit but also sub-volcanic epithermal Cu-Au porphyry deposit. In addition, there are at least two sources of ore-forming fluids in the Zhushahong mining area, high-temperature magmatic fluid and meteoric water. In response to fluid evolution times, mineralization process can be roughly divided into three metallogenic stages： silicate-sulfide, quartz-sulfide vein （main metallogenic stage, ore forming temperature is 200～340℃, and salinity is 2. 0% ～ 15% NaC1）, and carbonate sulfate-sulfide stages. Meanwhile, homogeneous temperature, salinity, and pressure imply that magmatic hydrothermal fluid has experienced boiling or unmixing processes during the fluid evolution and ore formation.

关 键 词：德兴 朱砂红 斑岩铜矿 流体包裹体 

分 类 号：P618.41[天文地球—矿床学]