Avalanche Statistics of Driven Granular Slides in a Miniature Mound

TL;DR

This study investigates avalanche size and timing statistics in miniature granular mounds under rain and vibration, revealing a transition from power-law to non-power-law behavior with increased driving rate.

Contribution

It demonstrates a generic crossover in avalanche statistics from power-law to non-power-law as the driving rate increases in miniature granular slides.

Findings

Avalanche size distribution follows a power-law with exponent ~-1.97 at slow driving rates.

Interevent times also follow a power-law with exponent ~-2.67 in slow-driven conditions.

Transition from power-law to non-power-law statistics occurs as driving rate increases.

Abstract

We examine avalanche statistics of rain- and vibration-driven granular slides in miniature sand mounds. A crossover from power-law to non power-law avalanche-size statistics is demonstrated as a generic driving rate $\nu$ is increased. For slowly-driven mounds, the tail of the avalanche-size distribution is a power-law with exponent $-1.97\pm 0.31$, reasonably close to the value previously reported for landslide volumes. The interevent occurrence times are also analyzed for slowly-driven mounds; its distribution exhibits a power-law with exponent $-2.670\pm 0.001$.