Seismic Impact of Industrial Blasts in Western Siberia and Induced Seismicity

Resumo

Based on data from regional seismic networks and experiments employing temporary networks, the degree of seismic impact of industrial blasts in southwestern Siberia is studied. Since the blasts at all mining enterprises were ripple-fired shots, magnitudes are studied proceeding from the total explosive charge and the dependence of magnitudes on the delay stage. On average, there is a slight increase in magnitudes with increase in total charge and the charge of a stage, but strong scatter of data from the averaged straight line is observed. It is quite common that large magnitudes are recorded for blasts with smaller charges of stages. The noted experimental features are explained by the coincidence of triggering time for wells in different rows: this intensifies the interference of seismic impact of incorrectly detonated blasts (the technology of ripple-fired shots is not rigorously implemented). The monitoring system made it possible to study the seismic impact of mining enterprises recovering mineral resources in the regional subsurface. Comparison with the recorded induced seismicity shows that open pit mines with the strongest industrial blasts do not demonstrate the strongest induced seismicity. The absence of technogenic earthquakes near excavations with high explosive energy has been established and, on the contrary, the existence of induced seismicity has been revealed in places where there is no direct blast impact on the activated zone.