摘要
By means of microscopy and laser Raman spectroscopy, the authors studied the fluid inclusions in petrography. The results show that there exist three-phase CO2-bearing and two-phase aqueous inclusions in gold ore; the fluid of NaC1-H2O-CO2 system went through immiscibility in ore-forming process. Ore-forming fluids were of low salinity (0. 82%- 5.40% NaCleqv), low density (0. 54-0.93 g/cm3 ) ; mineralization temperature were concentrated in 320℃-340℃ , with ore-forming pressure in 62-126 MPa and mineralization depth in 6.34-9.35 kin. The fluid inclusions in quartz are generally characterized by a small amount of CO2 and Na. Combined with recent results of the isotopic analysis for fluid inclusions and dating data, it was indicated that the main ore-forming fluids derived mainly from source of mantle-derived fluids with a small amount of magmatic fluid and meteoric water. The genetic type was mesothermal gold deposits involved by mantle-derived fluids.
By means of microscopy and laser Raman spectroscopy,the authors studied the fluid inclusions in petrography.The results show that there exist three-phase CO2 -bearing and two-phase aqueous inclusions in gold ore;the fluid of NaCl-H2O--CO2 system went through immiscibility in ore-forming process.Ore-forming fluids were of low salinity(0.82%-5.40%NaCleqv),low density(0.54-0.93 g/cm3);mineralization tempera-ture were concentrated in 320℃--340℃,with ore-forming pressure in 62-126 MPa and mineralization depth in 6.34-9.35 km.The fluid inclusions in quartz are generally characterized by a small amount of CO2 and N2.Combined with recent results of the isotopic analysis for fluid inclusions and dating data,it was indicated that the main ore-forming fluids derived mainly from source of mantle-derived fluids with a small amount of magmatic fluid and meteoric water.The genetic type was mesothermal gold deposits involved by mantle-derived fluids.