Self-affine Asperity Model for earthquakes

TL;DR

This paper introduces a fault dynamics model based on intersecting self-affine profiles, capturing key seismic features like magnitude distribution variability, stress buildup, and epicenter clustering, aligning well with observed earthquake behaviors.

Contribution

The model uniquely incorporates fractal fault geometry to explain non-universal earthquake magnitude distributions and clustering phenomena.

Findings

Non-universality of Gutenberg-Richter exponent

Presence of local stress accumulation before large earthquakes

Non-trivial space-time clustering of epicenters

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 release is proportional to the overlap interval. Our model exhibits some specific features which follow from the fractal geometry of the fault: (1) non-universality of the exponent of the Gutenberg-Richter law for the magnitude distribution; (2) presence of local stress accumulation before a large seismic event; (3) non-trivial space-time clustering of the epicenters. These properties are in good agreement with various observations and lead to specific predictions that can be experimentally tested.