The Qianhe gold mine is one of the most representative gold deposits in the Xiong'ershan region, which is located in the southern margin of North China Craton and is also an important gold producing region in China. The deposit of Qianhe is a medium-low temperature altered catallactic rock type Au deposit. The ore-forming fluid is mainly magmatic hydrothermal fluid, and the ore-forming material source is mainly from deep mantle source. In this research, we take the Qianhe gold deposit as an example to simulate the dynamic mineralization process. Through establishing a two-dimensional geological model, the steady-state and transient numerical simulations are carried out, respectively. Simulation results show that high-temperature ore-forming fluid from magma flows along the fault zone, and it heats the fault and surrounding rock achieving the temperature and pressure condition of mineralization. Moreover, total heat transferred by fluid is related to fault width, fluid temperature and pressure at the source of hydrothermal fluid, and the fault permeability. The higher the permeability of faults and the greater the pressure and temperature at the source are, the higher the hydrothermal velocity and advection heat flow density in faults are. Under the same heat flow density, the wider the faults and the greater the total heat transferred are, the more favorable the formation of gold deposits is in a relatively short period time to reach the temperature favorable to the formation of gold deposits under a specific pressure. We find that the fault permeability which varies several orders of magnitude has the most significant effect among these influencing factors. When the fault permeability is low, the hydrothermal metallogenic system in Qianhe area would need about 1 Ma to reach a stable and suitable metallogenic condition, while it needs only a millennium to reach a long and stable temperature and pressure metallogenic condition when the fault permeability is high.
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