Analysis of the formation conditions of slag debris flow and the study of its main provenance characteristics: taking Kangshan Gold Mine in Luanchuan County as an example

Luanchuan County has experienced many flash floods and debris flow disasters, and the potential development of slag debris flow is very typical. The biggest difference between slag debris flow and natural debris flow is the difference in provenance. Takes Kangshan Gold Mining Area in Luanchuan County as the research object, the formation conditions of the slag debris flow in the area are summarized and analyzed by investigating the topography, geomorphology, meteorology, hydrology, and debris flow provenance. Research on the macroscopic characteristics, particle size distribution, and permeability characteristics of major debris flow sources such as waste rock and slag, tailings sand, and residual slope soil in the area shows that the waste rock slag field belongs to gravel soil, and its uneven coefficient C_u=35.87, curvature coefficient C_c=1.5, with obvious particle size stratification law and good gradation. The average content of particles d≥2 mm in the waste rock and slag yard in the study area is 76.68%, belonging to the narrow debris flow type. The average permeability coefficient of waste rock and slag yard is 0.069 600 cm/s, which is 3.2 times of the permeability coefficient of natural debris flow（0.021 800 cm/s）, 4 times of the permeability coefficient of eluvial soil（0.017 320 cm/s）, and 37 times of the permeability coefficient of tailings sand（0.001 869 cm/s）. The permeability coefficient is positively correlated with coarse particle content of different debris flow sources.