High accuracy microseismic monitoring (2-4 m location error) offers a reliable evaluation of the position of the caving front associated with cave mining operations at Ridgeway Gold Mine. These estimates are employed to validate the results derived from direct geotechnical measurements.

The distribution of microseismic event locations defines the transition between unfractured and completely broken rockmass. The analysis of event mechanisms confirms the presence of both pure-shear and volumetric failure components, as expected by rock mechanics criteria. The changes in the pattern of microseismicity appear to be controlled by the material properties (e.g., stiffness, fracturation) of the geological domains through which the caving progressed.

Cezar I. Trifu1, Vladimir Shumila1, and Nat Burgio2
1 ESG, Kingston, Ontario, Canada
2 Stratavision, Orange, NSW, Australia