Susceptibility of Microseismic Triggering to Small Sinusoidal Stress Perturbations at the Laboratory Scale

Small transient stress perturbations are prone to trigger (micro)seismicity. In the Earth’s crust, these can be caused by various sources such as passage of seismic waves, forcing tides, or hydrological seasonal loads. A better understanding dynamic earthquake triggering is essential improve our physics and consideration hazard. Here, we study an experimental sandstone-gouge-filled fault system undergoing combined far field loading periodic (of variable amplitude frequency) at crustal pressure conditions. Microseismicity — in form acoustic emissions (AE) strains, stresses, continuously recorded order response microseismicity a function rate, amplitude, frequency perturbation. The observed AE distributions do not follow predictions either Coulomb failure model, taking into account both constant oscillation-induced strain rates, rate state model. susceptibility system’s confinement perturbation estimated, which highlights linear relation between observations agree with recent higher results on triggering. magnitude-frequency distribution AEs also computed. Gutenberg-Richter b-value oscillates oscillations. Our experiments may help complement influence low inertia phenomena seismicity, seismicity modulation tides loading.