Initiation of Tectonic Earthquakes during Underground Mining

Abstract

The influence of underground mine workings arranged nearby faults on the initiation of large seismic event is considered. Numerical modeling proves that amount of underground mine workings affects actual stiffness of rocks and initiates dynamic movements accompanied by intensive seismic radiation. As rock mass quality worsens, the effective shear modulus drops. The calculations show that the effective shear modulus lowers by 20% for the stopes on the same level, decreases 1.5 times in case of the stopes arranged on two levels and nearly halves for three levels. Such reduction in the actual shear stiffness of rock mass may be critical in terms of initiation of dynamic shift along a fault.