Study on the mechanism of repeated mining multi-aquifer water outburst in deep extremely close coal seams
Zhou Jinyan1, 2, 3
1. Hebei Coal Research Institute Co., Ltd., Xingtai 054000, China; 2. Key Laboratory of Mine Water Disaster Detection and Prevention and Control, National Mine Safety Administration, Xingtai 054000, China; 3. Hebei Key Laboratory of Mine Microseismicity, Xingtai 054000, China
The geological conditions of deep coal resources are complex. The occurrence characteristics of extremely close coal seams in Pingmei coal mine area are obvious. The extremely close coal seam group is repeatedly mined. The influence mechanism and manifestation law of mine pressure superposition are complex, and the difficulty of water prevention and control is increased. The purpose of this study was to explore the mechanism of water outburst in the process of repeated mining in deep extremely close coal seams. By means of theoretical analysis, field measurement and attribute classification, the spatial and temporal evolution law and water outburst mode of microseismic events in No.Ji17-33200 Face of Pingdingshan No.10 Coal Mine were analyzed. The results showed that the distribution of deep microseismic events in extremely close repeated mining was concentrated, and the microseismic response characteristics were different at location of the upper layer water outburst point, the increase of water volume and the pressure of the lower layer. Based on the temporal and spatial evolution of microseismic events and the analysis of microseismic attributes of each aquifer, a tree model of ' deep Cambrian limestone as the root, central Taiyuan Formation limestone as the trunk, and shallow water outburst as the crown ' was constructed. The Cambrian limestone was the main channel of the water diversion channel. The thin limestone aquifer presented the characteristics of ' huff and puff '. With the change of water volume, the shallow water outburst points were dispersed, which were controlled by the original rock fracture zone and the floor mining failure zone, mainly at the broken rock stratum, the concentrated mine pressure or the low-lying section. The tensile and shear properties of microseismic source changed with the change of channel and the increase and decrease of water volume. When the channel expanded, the tensile fracture was dominant. When the channel was closed, the tensile rupture was reduced. The study proposed a deep repeated mining ' tree model ' water outburst mechanism, which could improve the forewarning ability of repeated mining water disaster in close-distance coal seams, and provide a reference for the study of water prevention and control mechanism under similar conditions.
周金艳1, 2, 3. 深部极近距离煤层重复采动多含水层出水机理研究[J]. 煤炭与化工, 2025, 48(3): 1-7.
Zhou Jinyan1, 2, 3. Study on the mechanism of repeated mining multi-aquifer water outburst in deep extremely close coal seams. CCI, 2025, 48(3): 1-7.