Component,ore-forming fluids and material sources in the xiajiadian gold deposit of shanyang county,shaanxi

Main ore-bearing rocks in the Xiajiadian gold deposit are breccias which are composed of mud-iron-carbon siliceous slate,siliceous rock and silicated fragment.Silicifacation are close wallrock alteration with gold mineralization.Gold occurs mainly as fissure fillings,subordinately as intergranular grains,and seldom as inclusions.Gold exists as natural gold.There are abundant of fluid inclusions.Ore-forming temperature decreases along with mineralization.Ore-forming fluids change from KCl-CO2-NaCl system to H2O-CO2-NaCl system.Ore-forming condition is weakly reductive,and gold is derived from carbon siliceous slate.