Geological risk evaluation of open-pit mines of Xujiagou in Anyang based on UAV survey and analytic hierarchy process

Mineral resources are an important foundation for social and economic development, and in the context of integrating social development and ecological construction, prevention, control and ecological environment restoration of mine geological risks have become the focus of mining research. The classification and quantification of mine geological risk is the basis of prevention and restoration, which is conducive to the development of management measures according to local conditions. This paper evaluates the geological risk of open-pit mines group of Xujiagou in Anyang based on UAV survey and analytic hierarchy process, and summarizes three main geological risks of slope failure, pit collapse and soil erosion according to the survey results, and selects four factors for each risk layer, with a total of 12 evaluation indexes, and utilizes ArcGIS raster computation module to superimpose and analyze the 12 evaluation factors selected in this study. The results show that the areas of high risk zone, significant risk zone, general risk zone and slight risk zone are 13 500 m², 39 000 m², 26 750 m² and 45 750 m² respectively, accounting for 10.8%, 31.2%, 21.4% and 36.6% of the total area of the study area; the comprehensive mine geological risk is ranked as Hexi Shengli Zone II<Yulong Zone I<Yu’an Zone III. From Yulong Zone I to Yu’an Zone III, as the area of the study sub-area decreases, the contribution rate of slope failure risk gradually decreases, and the risk of pit collapse and soil erosion gradually increases. The results show that the slope failure score and mine geology score show a bimodal trend, while the pit collapse and soil erosion risks show a single peak. This paper proposes management measures such as dangerous rock removal, slag backfilling, slope trimming, guest soil restoration of forested and cultivated land, and conservation management, so as to reduce the mine geological risk and repair the mine ecology.