湖南洪江市石榴寨金矿流体包裹体特征及地质意义

Characteristics of fluid inclusions and geological implication of Shiliuzhai gold deposit in Hongjiang City,Hunan

为深入了解石榴寨金矿床的成矿机制,在矿床地质特征研究的基础上,对该矿床主成矿阶段流体包裹体进行了系统研究,结果表明该矿床内流体包裹体主要为气液两相,少量为纯液相包裹体。成矿流体主要为中低温(180℃~320℃)、低盐度[w(NaCleq):6%~16%]、低密度(0.84 g/cm^(3)~1.02 g/cm^(3))的NaCl-H2O体系,成矿环境为低压(8.82 MPa~39.56 MPa)、浅成(0.9~4.0 km)环境。成矿流体表现出岩浆热液和大气降水的混合流体特征,结合矿区矿体地质特征,认为石榴寨金矿为中低温岩浆热液型矿床。该研究对区内进一步开展找矿工作有一定的指导价值。

In order to understand the mineralization mechanism of Shiliuzhai gold deposit,based on the study of the geological characteristics of the deposit,this article systematically studies the fluid inclusions in the main ore-forming stage of Shiliuzhai gold deposit.The result shows that the fluid inclusions in the deposit are mainly two phases of gas and liquid,with a small amount of pure liquid inclusions.The ore-forming fluid is mainly a NaCl-H2O system with medium and low temperature(180℃-320℃),low salinity(6%-16%)and low density(0.84 g/cm^(3)-1.02 g/cm^(3)).The ore-forming environment is a low pressure(8.82 MPa-39.56 MPa),shallow depth(0.9-4.0 km)environment.The ore-forming fluid exhibits the characteristics of a mixed fluid of magmatic hydrothermal fluid and atmospheric precipitation.Based on the general geological characteristics of the mining area,Shiliuzhai gold deposit is considered to be a medium-low temperature magmatic hydrothermal deposit.It has a certain guiding value for the further development of prospecting work in the research area.