Analysis of Mining Earthquake Patterns and Research on Control Measures in Yanzhou Mining Area

The occurrence of mining tremor significantly impacts the safety of mine production. Taking three rockburst-prone areas in the Yanzhou mining district as the research background, this study analyzes the correlation between geology, mining, surface subsidence, and rockburst magnitude and frequency, while verifying the effectiveness of in-situ floor blasting for fault control. The findings indicate: high-magnitude rockburst frequency is strongly correlated with red bed thickness and the degree of variation in the distance between red beds and coal seams. Within a certain range, greater red bed thickness and closer proximity to coal seams result in higher high-magnitude rockburst frequency. The frequency is closely related to the size of the goaf area and the advancing speed of the working face, with peak frequency occurring during the goaf formation period. Mining depth has a certain influence on rockbursts, while cessation duration shows no significant correlation. High-energy rockbursts are more likely to occur at points of rapid change or peaks in the surface subsidence rate curve. Field monitoring data reveal that floor blasting to break the fault in the 93-21 working face of Nantun Coal Mine significantly reduces impact effects, effectively lowering rockburst risks in the working face.