title: Common dependence on stress for the statistics of granular avalanches and earthquakes.
abstract: Both earthquake size-distributions and aftershock decay rates obey power laws. Recent studies have demonstrated the sensibility of their parameters to faulting properties such as focal mechanism, rupture speed or fault complexity. The faulting style dependence may be related to the magnitude of the differential stress, but no model so far has been able to reproduce this behaviour. Here we investigate the statistical properties of avalanches in a dissipative, bimodal particulate system under slow shear. We find that the event size-distribution obeys a power law only in the proximity of a critical volume fraction, whereas power-law aftershock decay rates are observed at all volume fractions accessible in the model. Then, we show that both the exponent of the event size-distribution and the time delay before the onset of the power-law aftershock decay rate are decreasing functions of the shear stress. These results are consistent with recent seismological observations of earthquake size-distribution and aftershock statistics.
authors.affiliation: Earthquake Research Institute, University of Tokyo, 113-0032 Tokyo, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Hatano
authors.affiliation: Institut de Physique du Globe de Paris, Sorbonne Paris Cité, Univ Paris Diderot, UMR 7154 CNRS, 1 rue Jussieu, 75238 Paris, Cedex 05, France.
authors.forename: Clément
authors.initials: C
authors.lastname: Narteau
authors.affiliation: Institute of Earthquake Prediction Theory and Mathematical Geophysics, Profsoyuznaya str., 84/32, Moscow 117997, Russia.
authors.forename: Peter
authors.initials: P
authors.lastname: Shebalin