Bewick, RP, Kaiser, PK & Bawden, WF 2014, 'Shear rupture – two case studies from a deep mine', in M Hudyma & Y Potvin (eds), Proceedings of the Seventh International Conference on Deep and High Stress Mining
, Australian Centre for Geomechanics, Perth, pp. 641-658, https://doi.org/10.36487/ACG_rep/1410_45_Bewick
When a fault-slip event mechanism is determined, it is easy to assume that there must be a fault present to generate the event. A pre-existing fault is not needed to create a fault-slip event. Fault rupture (the failure process in brittle rocks which occurs under confined conditions) also generates a fault-slip focal mechanism. Fault ruptures will commonly occur far from mining, in abutments, wide pillars, and sills. First the rupture process is overviewed. Then two mining fault rupture case examples are summarised to show the fault rupture process, final rupture geometry, and energy release potential observed in the field conform to theoretical understanding. In this article it is shown that the fault rupture process and energy release depends on the boundary condition (system stiffness) surrounding the failure process. While seemingly theoretical, the findings have practical significance with respect to rock mass characterisation, microseismic monitoring, rock mass behaviour back analysis, and mining strategy.
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