Pulse-like, crack-like, and supershear earthquake ruptures with shear strain localization

Eric G. Daub, Jean M. Carlson, Mary Elizabeth Manning

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

We incorporate shear strain localization into spontaneous elastodynamic rupture simulations using a shear transformation zone (STZ) friction law. In the STZ model, plastic strain in the granular fault gouge occurs in local regions called STZs. The number density of STZs is governed by an effective disorder temperature, and regions with elevated effective temperature have an increased strain rate. STZ theory resolves the dynamic evolution of the effective temperature across the width of the fault zone. Shear bands spontaneously form in the model due to feedbacks amplifying heterogeneities in the initial effective temperature. In dynamic earthquake simulations, strain localization is a mechanism for dynamic fault weakening. A shear band dynamically forms, reduces the sliding stress, and decreases the frictional energy dissipation on the fault. We investigate the effect of the dynamic weakening due to localization in generating pulse-like, crack-like, and supershear rupture. Our results illustrate that the additional weakening and reduction of on-fault energy dissipation due to localization have a significant impact on the initial shear stress required for supershear or pulse-like rupture to propagate on a fault.

Original languageEnglish (US)
Article numberB05311
JournalJournal of Geophysical Research D: Atmospheres
Volume115
Issue number5
DOIs
StatePublished - 2010
Externally publishedYes

Fingerprint

earthquake rupture
shear strain
Shear strain
Earthquakes
crack
earthquakes
cracks
shear
Cracks
rupture
shear band
Shear bands
energy dissipation
pulses
Energy dissipation
temperature
elastodynamics
fault gouge
Temperature
strain rate

ASJC Scopus subject areas

  • Geochemistry and Petrology
  • Geophysics
  • Earth and Planetary Sciences (miscellaneous)
  • Space and Planetary Science

Cite this

Pulse-like, crack-like, and supershear earthquake ruptures with shear strain localization. / Daub, Eric G.; Carlson, Jean M.; Manning, Mary Elizabeth.

In: Journal of Geophysical Research D: Atmospheres, Vol. 115, No. 5, B05311, 2010.

Research output: Contribution to journalArticle

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