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The Wadi Sharis orogenic gold deposit in northwestern Yemen is related to the fault and shear zones vein at medium depth in the crust in the Neoproterozoic meta-sedimentary and meta-volcanosedimentary succession of greenschist to amphibolite facies metamorphism.Three distinct fluid inclusion types have been identified in the gold-bearing quartz sulphide veins of the deposit:(1) type I:vapour-liquid two-phase(VH2O-LH2O),(2) type II:three-phase CO2(VCO2-LH2O-LCO2) and(3) type III:vapour-rich(LCO2-VCO2) inclusions.Six analysis of individual fluid inclusion indicate the fluid inclusions comprise mainly of H2O and CO2.Formation P-T conditions recorded by fluid inclusions in quartz crystals correspond to 180℃-380℃ and up to 130 MPa,as indicated by high-density CO2 bubbles(up to 0.98 g/cm3) observed in some inclusions.The estimated crystallization pressures correspond to approximately 4-10 km of overburden,assuming a lithostatic load.The salinity ranges from 0 to 22 wt%.The deposit holds at 0.2-5 g/t Au and contains low-moderate salinity.
The Wadi Sharis orogenic gold deposit in northwestern Yemen is related to the fault and shear zones vein at medium depth in the crust in the Neoproterozoic meta-sedimentary and meta-volcanosedimentary succession of greenschist to amphibolite facies metamorphism. Unique distinct fluid inclusion types have been identified (2) type II: three-phase CO2 (VCO2-LH2O-LCO2) and (3) in the gold-bearing quartz sulphide veins of the deposit: ) type III: vapor-rich (LCO2-VCO2) inclusions.Six analysis of individual fluid inclusions the fluid inclusions include mainly H2O and CO2. Formation PT conditions recorded by fluid inclusions in quartz crystals correspond to 180 ° C-380 ° C and up to 130 MPa, as indicated by high-density CO2 bubbles (up to 0.98 g / cm3). Observed values correspond to approximately 4-10 km of overburden, assuming a lithostatic load. The salinity ranges from 0 to 22 wt%. The deposit holds at 0.2-5 g / t Au and contains low-moderate salinity.