Research on correlation between regional seismic characteristics and coal mine rockburst in Hegang

Natural earthquakes and coal mine rockbursts are both transient fracturing processes of stress release in crustal rock mass. Current research primarily investigates the correlation between earthquakes and rockbursts from either the geodynamic environment or focal mechanism solutions separately. However, examining their relationship in terms of geodynamic environments, spatiotemporal characteristics, and focal mechanism solutions can provide new parameters for dynamic risk assessment in mining areas, thereby improving accuracy of early warning. Taking natural earthquakes and coal mine rockbursts in Hegang as the research backgrounds, and based on seismic data from multiple platforms of seismic stations and mobile seismic monitoring stations, this study analyzed the geodynamic environment and spatiotemporal correlation between regional seismic characteristics and coal mine rockbursts. The results showed that: ① the southern Hegang mining area exhibited significant seismic activities, displaying a NNE-trending linear distribution, while coal mine rockbursts showed an NE-trending distribution. The two exhibited a parallel conjugate relationship, consistent with the NE-trending distribution pattern of seismic activities in the regional large-scale geological structure, the Yilan-Yitong fault zone. This indicated that crustal activities in the southern Hegang mining area were controlled by the regional geodynamic environments. ② Correlation analysis of the timing, location, and frequency of earthquakes and coal mine rockbursts during the same period demonstrated strong spatiotemporal consistency. In the Junde coal mine field, earthquake magnitudes typically ranged between 1.2 and 1.6, with frequencies of 2-5 events. Coal mine rockbursts predominantly occurred near the magnitude contour line of 1.4 and the frequency contour line of 5 events. The frequent occurrence of small earthquakes reflected that the energy of the regional crust was in a stage of gradual release, creating favorable conditions for coal mine rockburst development. ③ Focal mechanism solution analysis revealed that the compressive stress axis orientation of earthquakes was consistent with that of high-energy microseismic events in coal mines, indicating a unified tectonic stress field and energy conditions. This further manifested that earthquakes and coal mine rockbursts in Hegang shared the same geodynamic environments.