Simulation of Water Level Changes and Leakage Prediction in the Burnt Rock Aquifer: A Case Study of Arid Coal Mining Regions in Western China
摘要
Determining the sources and quantities of mine water recharge is critical for ensuring the safety of mining operations and protecting aquifers. This study focused on simulating and predicting water level changes, leakage locations, and leakage quantities in the burnt rock aquifer of the Yushuquan coal mine using the unstructured grid (UGrid) module and the MODFLOW model within the groundwater modeling system (GMS). The results indicate that the burnt rock aquifer serves as a direct source of replenishment for the coal-bearing strata of the Lower Taliqike Formation, with an estimated leakage quantity of ≈ 5200 m3/d. Leakage points are primarily located around boreholes G11 (-3600 m3/d) and G20 (-1000 m3/d) in the central syncline axis region, and borehole G18 (-600 m3/d) in the western syncline axis region. Water level changes in the aquifer exhibit a convergence trend toward the syncline axis from all directions, with the overall flow direction moving from the east and west toward the central region. Notably, the water level in the western region declines rapidly, whereas the decrease in the eastern region is more gradual. Currently, groundwater in the central and western regions is almost completely drained, whereas the groundwater level in the eastern region remains between 1772 and 1778 m, and the southern region maintains a relatively constant water level of ≈ 1792 m. These findings serve as a theoretical basis for predicting mine water inflow and identifying grouting locations in the water-conducting fracture zone during subsequent mining operations.