Hydrogeological characteristics and water hazard prevention and control techniques of the lower segment aquifer of Zhiluo Formation in Shuanglong Coal Mine of Huangling Mining Area

In view of the previous issues in the research on the Zhiluo Formation aquifer in Shuanglong Coal Mine, such as insufficiently detailed exploration data, incomplete analysis of water hazard influential factors, and lack of targeted prevention and control measures, a special study on the hydrogeological characteristics and prevention and control measures of this aquifer is conducted to provide a precise basis for water hazard prevention and control during the mining of the NO.2 coal seam in the mine. CG5 and CG6 hydrological long-term observation holes were established, and methods such as core drilling, geophysical logging, and pumping tests were employed. The height of the water-conducting fracture zone was predicted by coupling empirical formulas with the measured fracture-extraction ratio method. The characteristics of the aquifer were analyzed from multiple dimensions, including spatial distribution and water-rich property, and the influential factors of water disasters were analyzed. It is confirmed that the lower segment of the Zhiluo Formation is a confined aquifer developed throughout the entire area, with an average thickness of 59.55 m and low water-rich property. The permeability coefficients of CG5 and CG6 are 0.002493 m/d and 0.0108 m/d, respectively, and both have a hydrochemical type of HCO₃-Na. The maximum height of the water-conducting fracture zone in NO.2 coal seam is 36.99 m, which has not breached the top of the Yan'an Formation. The water hazard threat is mainly concentrated near the skylight, and two types of water hazard threat zones have been identified. By establishing a comprehensive lifecycle water hazard prevention and control system encompassing "comprehensive exploration, engineering prevention and control, and dynamic monitoring", precise prevention and control of water hazards in the lower segment of the Zhiluo Formation aquifer can be achieved, ensuring safe production in coal mines.