GeoEngSoft Technologies

Deep mining in the Sudbury Basin can trigger seismic events termed rockbursts by miners. There are two fundamantal types of damaging events; 1) Strainbursts at excavation faces that are rock ejections due to excess stress conditions, and 2) Fault or shear-slips that have earthquake characteristics due to the physical slip or movement of the earth. These mining-induced tremors or rockbursts are much smaller in magnitude than global (e.g. Pacific ring-of-fire) earthquakes due to their limited slip surface.

Why the term "mining-induced"? Sudbury is located in the stable part of the Canadian Shield and basically; no mining, no seismicty in the basin. The prime example is the Vale strike in 2009 and the lack of Sudbury Basin underground seismic activity that year, apart from small magnitude surface blasting for road construction, e.g., Highway 400 south of Sudbury.

Despite the relatively small rockburst magnitudes (compared to tectonic earthquakes), it is due to the close proximity of mine personnel to the event hypocenters (location in the earth where rock rupture starts), that both types of rockburts can cause extensive damage and and have caused fatalities.

The 20 largest mining-induced fault-slip events (> 3.4 MN) in the Sudbury Basin, and two rock fall events that have resulted in fatalities, are mapped below.

This page is under development, so if you want to contribute additional information, let me know to add it. About 230 smaller (2.7 to 3.4 MN) rockbursts are plotted as small blue diamonds - looks less due to overlapping event locations, also note the source location errors (~kms).