Frictional relaxation in avalanches

Snow Avalanches, Ice Avalanches and Glacier Surges

Granular avalanches in fluids.

Three regimes of granular avalanches in fluids are put in light depending on the Stokes number St which prescribes the relative importance of grain inertia and fluid viscous effects and on the grain/fluid density ratio r. In gas (r>>1 and St>1, e.g., the dry case), the amplitude and time duration of avalanches do not depend on any fluid effect. In liquids (r approximately 1), for decreasing St,...

Avalanches in Wood Compression.

Wood is a multiscale material exhibiting a complex viscoplastic response. We study avalanches in small wood samples in compression. "Woodquakes" measured by acoustic emission are surprisingly similar to earthquakes and crackling noise in rocks and laboratory tests on brittle materials. Both the distributions of event energies and of waiting (silent) times follow power laws. The stress-strain re...

Avalanches in Fractional Cascading

This paper studies the distribution of avalanches in fractional cascading, linking the behavior to studies on self-organized criticality, in particular, the power law behavior of the Bak-Tang-Wiesenfeld sandpile model. Unlike the sandpile model, however, we prove that fractional cascading does not exhibit abelian properties. While fractional cascading has maximum gap size as a system parameter ...

Neuronal Avalanches

It has recently been suggested that, in order to provide the richness of behavior which is seen empirically, the brain must operate in a critical regime between a phase of order and disorder [1]. In particular, such critical behavior is exhibited in what is termed neuronal avalanches. These cascades of synaptic activity have been seen both in vitro and in vivo [6]. Several models have been put ...