Energetics of strain localization in a model of seismic slip

Ann M. Hermundstad, Eric G. Daub, & Jean M. Carlson

Published 2010, SCEC Contribution #1328

We quantify the energy dissipated to heat and to local disorder in a sheared layer of granular fault gouge. Local disorder is modeled using Shear Transformation Zone (STZ) Theory, a continuum model of non-affine deformation in amorphous solids that resolves spontaneous localization of strain. Strain localization decreases the total energy dissipated during slip. In addition, a fraction of this energy is dissipated to increasing local disorder as the material is sheared, thereby decreasing the amount of energy dissipated as thermal heat. We quantify the heat dissipated per unit area as a function of total slip in the presence and absence of strain localization and test the parameter dependence of these calculations. We find that less heat is dissipated per unit area compared to results obtained using a traditional heuristic energy partition.

Key Words
strain, amorphous materials, friction, slip rates, deformation, layered materials, temperature, solid phase, rupture, granular materials, gouge, quantitative analysis, shear, seismic energy, earthquakes, faults, energy

Hermundstad, A. M., Daub, E. G., & Carlson, J. M. (2010). Energetics of strain localization in a model of seismic slip. Journal of Geophysical Research: Solid Earth,.