摘要
Fluid inclusions in the leucosomes of Wadi Feiran migmatites showed that CO2, H2O and (H2O-CO2) fluids were likely to have been present when partial melting began in these rocks. Low salinity, aqueous fluid, to a lesser extent, CO2-rich fluids are the most abundant fluids. The present study suggests that high-density CO2 inclusions were formed at the earliest stage, while H2O inclusions were formed at the late stage. In an intermediate stage, low-density CO2 and H2O, CO2 inclusions were formed. At the early stage of uplift and during melt crystallization, the CO2-bearing vapour was trapped at grain boundaries. At the late stage of uplift, H2O released at the time of crystallization of the melt was trapped as inclusions.
Fluid inclusions in the leucosomes of Wadi Feiran migmatites showed that CO2, H2O and (H2O-CO2) fluids were likely to have been present when partial melting began in these rocks. Low salinity, aqueous fluid, to a lesser extent, CO2-rich fluids are the most abundant fluids. The present study suggests that high-density CO2 inclusions were formed at the earliest stage, while H2O inclusions were formed at the late stage. In an intermediate stage, low-density CO2 and H2O, CO2 inclusions were formed. At the early stage of uplift and during melt crystallization, the CO2-bearing vapour was trapped at grain boundaries. At the late stage of uplift, H2O released at the time of crystallization of the melt was trapped as inclusions.