Self-Affine Asperity Model for Earthquakes

Abstract

A model for fault dynamics consisting of two rough and rigid Brownian profiles that slide one over the other is introduced. An earthquake occurs when there is an intersection between the two profiles. The energy released is proportional to the overlap interval. Our model exhibits some specific features which follow from the fractal geometry of the fault: (1) nonuniversality of the exponent of the Gutenberg-Richter law for the magnitude distribution, (2) presence of local stress accumulation before a large seismic event, and (3) nontrivial space-time clustering of the epicenters.