通过流体包裹体岩相学、显微测温学和包裹体稀土元素分析,研究青海德合龙洼铜金矿床成矿流体性质和演化。研究结果表明:流体包裹体主要为气液两相包裹体,另有少量液相包裹体;包裹体气相成分主要以H2O和CO2为主。流体包裹体的均一温度为327~367℃,流体盐度为3.4%~6.4%,流体密度为0.55~0.88 g/cm3,为中高温、低盐度、中等密度和中等压力的成矿流体;石英和黄铁矿包裹体中,轻稀土富集,重稀土亏损,具有负铕异常。
Based on the study of the fluid inclusion,micro-thermometry and rare earth element analyses,the characteristics of ore-forming fluid,fluid evolution and the origin of the Dehelongwa copper-gold deposit were discussed and systematically studied.The results show that these inclusions consist of phases of gas and liquid,with minor inclusions of liquid,and the compositions of gas in the inclusions are H2O and CO2.The homogenization temperature,salinity and density of fluid for the major mineralization phase range from 327 ℃ to 367 ℃,3.4% to 6.4% and 0.55 g/cm3 to 0.88 g/cm3,respectively.In fluid inclusions of quartz and pyrite,LREE(light rare earth element) is enriched,HREE(heavy rare earth element) is loss,and negative Eu is abnormal.