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experimentally from studies of earthquakes and rock bursts at high stress levels. The behaviour is caused by
the intrinsic nature of the fault structure, which is an echelon of blocks operating as hinges, essentially
eliminating friction at high confining pressure of a certain displacement range. The paper demonstrates that,
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current fracture and in the opposite direction. This mechanism triples the fault propagation speed. Junctions
formed at the meeting of the approaching segments help to accommodate the fault displacement and can
significantly decrease the fault strength - thus contradicting the general belief that junctions represent
strength barriers impeding the fault motion. The improved understanding of the fracture process is important
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Paradoxical Features of Primary Shear Fractures and General Faults B.G. Tarasov, M.F. Randolph
182 Deep Mining 07, Perth, Australia