Precursors, aftershocks, criticality and self-organized criticality

TL;DR

This paper introduces a hierarchical fault network model demonstrating self-organized criticality in earthquakes, reproducing key empirical laws and revealing precursors and aftershock patterns as signs of approaching large events.

Contribution

The study presents a simple hierarchical model that captures earthquake phenomenology, including precursors, aftershocks, and power-law distributions, highlighting the dynamical criticality of large seismic events.

Findings

Power law Gutenberg-Richter distribution of earthquake sizes

Precursor energy release follows a time-to-failure power law with log-periodic structures

Large earthquakes act as dynamical critical points with associated precursors and aftershocks

Abstract

We present a simple model of earthquakes on a pre-existing hierarchical fault network. The system self-organizes on long time scales in a stationary state with a power law Gutenberg-Richter distribution of earthquake sizes. The largest fault carries irregular great earthquakes preceded by precursors developing over long time scales and followed by aftershocks obeying an Omori's law. The cumulative energy released by precursors follows a time-to-failure power law with log-periodic structures, qualifying a large event as an effective dynamical (depinning) critical point. Down the hierarchy, smaller earthquakes exhibit the same phenomenology, albeit with increasing irregularities.