延边浅成高硫化热液金矿床的成矿流体起源与演化:以杜荒岭和九三沟矿床为例

发布时间：2018-06-09 23:30

  本文选题：流体包裹体 + 稀有气体同位素　； 参考：《吉林大学学报(地球科学版)》2017年05期

【摘要】：杜荒岭和九三沟矿床是延边地区两个典型的浅成热液高硫化型金矿床,两者距离不足10km。本文运用显微测温、激光拉曼成分测试和稀有气体同位素对这两个矿床的蚀变岩和矿石中的石英内流体包裹体进行研究,以便揭示成矿流体的起源和演化过程。测温及拉曼测试结果表明:蚀变早期矿化阶段主要气体成分为CO_2、N_2的两相流体包裹体,发育少量高盐度(33.4%~48.1%)高温(410~470℃)的流体包裹体,其为深部斑岩成矿系统与后期浅成矿化流体叠加的产物;主成矿阶段均一温度为90~330℃,盐度为0.4%~44.9%,成分以H2O为主,含少量的CO_2;富气相、富液相及含石盐子晶多相的流体包裹体共存,表明流体发生了沸腾作用,这些流体包裹体被捕获的深度为100~500 m,代表浅成矿化的主要流体。稀有气体同位素结果表明:3 He/4 He值为0.009 6~0.020 6Ra,20 Ne/22 Ne、21 Ne/22 Ne值分别为9.734~9.987和0.030 9~0.040 6,40 Ar/36 Ar为1 302.4~4 433.6。上述研究结果表明,延边地区杜荒岭和九三沟金矿早期成矿流体为携带Au、Ag、Cu等成矿元素的高温、高氧化的岩浆气,主成矿阶段地壳流体的混入导致沸腾作用,晚期转以低温低盐度的大气水为主。
[Abstract]:Duhuangling and Jiusangou deposits are two typical epithermal high sulphide gold deposits in Yanbian area with a distance of less than 10km. In this paper, the fluid inclusions in alteration rocks and ores of these two deposits are studied by means of microthermometry, laser Raman spectroscopy and rare gas isotopes in order to reveal the origin and evolution of ore-forming fluids. The results of temperature measurement and Raman measurement show that the main gas composition in the early mineralization stage of the alteration is the two-phase fluid inclusions of CO _ 2O _ 2N _ T _ 2, and a small amount of fluid inclusions with high salinity of 33.4% and 48.1 鈩，

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