Qualitative study of a geodynamical rate-and-state model for elastoplastic shear flows in crustal faults

TL;DR

This study extends a geodynamical rate-and-state model for crustal faults by incorporating damage and aging effects, analyzing steady states, localization, and seismic cycle behaviors through computational experiments.

Contribution

It introduces a bulk variant of the Dieterich-Ruina model combining damage and aging, with analysis of steady states and fault localization.

Findings

Demonstrates stick-slip seismic cycles in damage-free variant

Shows stable slip at high velocities

Analyzes localization of the elastic response

Abstract

The Dieterich-Ruina rate-and-state friction model is transferred to a bulk variant and the state variable (aging) influencing the dissipation mechanism is here combined also with a damage influencing standardly the elastic response. As the aging has a separate dynamics, the overall model does not have a standard variational structure. A one-dimensional model is investigated as far as the steady-state existence, localization of the ataclastic core, and its time response, too. Computational experiments with a damage-free variant show stick-slip behavior (i.e. seismic cycles of tectonic faults) as well as stable slip under very large velocities.