The magmatic-hydrothermal metallogenic system may show similar evolution characteristics of the ore-forming fluids, which closely accompanied with the early magmatic evolution and with involvement of meteoric water in the late stage. However, the distinct mineralization associated with the same magmatic processes may also show difference in the characteristics, components and evolution of the ore-forming fluid, and precipitation mechanism of the ore-forming materials. In this paper, we studies the Shedong quartz-vein type W-Mo deposit and the Baoshan porphyry Cu deposit, which both hosted in the Sheshan composite pluton. The W-Mo ore bodies occurred in the Caledonian Sheshan biotite granodiorite with quartz veinlets while the Cu ore bodies show disseminated distributed in the Late Yanshanian concealed Baoshan porphyry granite. The fluid inclusion data of the Shedong W-Mo deposit show that the homogenization temperatures range from 180 ℃ to 320 ℃ and from 340 ℃ to 440 ℃. The main peak varies from 180 ℃ to 320 ℃. The peak salinity range from 0 to 10%, from 16% to 20%, and from 30% to 34% respectively, and centralizes in the range of 0 to 10% NaClequiv.（n = 177）, which indicates that the ore-forming fluid of the Shedong W-Mo deposit belongs to the H2O-NaCl±CO2 system with moderate-high temperature and moderate-low salinity. The homogenization temperatures fluid inclusions data in the Baoshan porphyry Cu deposit range from 136.6 ℃ to 440.0 ℃ and the peak is 240 ℃ to 360 ℃. The salinity centralizes in the range of 0.18% to 34.83% NaClequiv.（n = 154）, which indicates that the ore-forming fluid of the Baoshan Cu deposit belongs to the NaCl-H2O-KCl±CO2 system with mid-high to high temperature and high salinity. Thus, we can conclude that the evolution of the ore-forming fluid of the Shedong lode W-Mo deposit experienced the process of the gradual mixing of the early magmatic fluid and involvement of meteoric water in the late stage. The fluid mixing may be play an important role in the ore precipitation. The evolution of the ore-forming fluid of the Baoshan porphyry Cu deposit experienced the mid-high temperature initial fluid of early magma crystallization differentiation differs to high temperature, low salinity fluid and high temperature, high salinity fluid. Fluid boiling and phase separation play an important role in the migration and precipitation of metal elements.
Wang Xinyu Yang Zhen Zhang Qizuan Li Hailong Liu Xijun Fu Wei Wang Youchen. Characteristics of ore-forming fluids associated with magmatic-hydrothermal mineralization system： A case study from the Shedong quartz-type W-Mo deposit and the Baoshan porphyry Cu deposit[J]. Chinese Journal of Geology, 2019, 54(4): 1399-1415.