Characteristics of Fluid Inclusion and Metalogenic Mechanism of Liuli Tungsten Deposit of Damingshan Region,Guangxi
The Liuli tungsten deposit in Guangxi Province shows great prospecting potential,and this paper studies the mineralization mechanism based on the characteristics of ore body,ore rocks and fluid inclusions.The tungsten ore body is controlled by fractures,and the ore type is mainly quartz vein tungsten ore with occasionally greisen tungsten ore.The ore-forming process could be roughly divided into two stages.The early stage is the molybdenite-greisen stage,and the late stage is the scheelite-quartz stage.The fluid inclusions in quartz mainly consist of aqueous solution(W type),very little CO2-H2O(C type)and pure gas(PC type).The homogenization temperatures of the fluid are within the range of 140~382℃,with an average of 263℃,and the salinities are within the range of 0.18~12.68wt.%NaCl,with an average of 4.83wt.%NaCl,and the densities are within the range of 0.62~0.98 g/cm3,and the main components of gases are CO2 and H2O with low peak values.Fluid inclusion data combined with the phase separation temperature of sphalerite-chalcopyrite solid solution show that the mineralizing fluid should be characterized by low-salinity,medium-high temperature and CO2-depletion,and could be defined as H2O-CO2-NaCl system.The scheelite-quartz stage(late stage)is the main mineralizing stage of this deposit and the average homogenization temperatures from the early stage to and the late stages of the Liuli tungsten deposit shows a decreasing trend,hence this decrease in homogenization temperature could be the main mineralizing mechanism.
quartz-vein type tungsten depositfluid inclusionhomogenization temperature decreaseore-forming mechanismLiuli tungsten depositDamingshan,Guangxi Province