Dynamic Modelling of a Fault and Dyke in the Vicinity of Mining
In order to gain an understanding of fault and dyke behaviour, a series of numerical models have been investigated. The dynamic finite difference program WAVE (Hildyard et al. 1995) is used for the modelling of a stope in a deep mine. The slip along a vertical discontinuity, situated within the positive excess shear stress lobe of the stope, initiates seismic waves. The stope-discontinuity geometry is modelled in both two and three dimensions. The fault is modelled by reducing the fault cohesion instantaneously to zero, or by applying a slip-weakening law to the fault interface. Peak particle velocity values at the stope were stored in WAVE to compare the different mining scenarios. Results from using WAVE in three dimensions show that if the angle between the face direction and the strike of the fault or dyke is kept at more than 35°, then it decreases the possible seismic event due to slip on the discontinuity.