Characteristics of seismic hazard in mines: Keynote Lecture
Aleksander J. Mendecki
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Abstract
Despite its limitations the power law size distribution hazard estimates offers obvious benefits. It provides a useful association between its parameters and seismic hazard related factors. The �-value correlates positively with the stiffness of the system, with rock mass and mine layout heterogeneities, with the predictability of larger events and with the influence of small events on stress transfer in the rock mass. It also gives an insight into the fundamental scaling relation between seismic potency and radiated seismic energy, logE = (�P =�E)log P + (1=�E)log (�E=�P ), where �P , �P , �E, �E are parameters of the potency, P, and the energy, E, power laws respectively. Importantly, it is simple and reasonably well understood by mine seismologists and geotechnical practitioners. Because seismic events in mines follow production it is useful to distinguish between the observed hazard, estimated in the time domain, and seismic hazard potential which, due to the intermittent nature...
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