Stick-slip shear failure along bimaterial interfaces: An experimental study on granite and basalt

Characteristics of stick-slip shear failure under mode II conditions are experimentally investigated using a bimaterial system (consisting of granite and basalt) with a simulated fault. This experimental study is concerned with the effects of normal stress, shear rate, and fault roughness on the stick-slip behaviors along the heterogeneous faults. Highly non-uniform stress distribution along the simulated fault dictates the initiation of stick-slip failure. The nucleation starts at a firstly yielded material point, and as the energy accumulates in the heterogeneous fault, the nucleation zone is progressively formed and transited into unstable rupture. This experimental study aims at gaining scientific insights regarding earthquake source processes.