Source properties of dynamic rupture pulses with off-fault plasticity

Handle URI:
http://hdl.handle.net/10754/552165
Title:
Source properties of dynamic rupture pulses with off-fault plasticity
Authors:
Gabriel, A.-A.; Ampuero, J.-P.; Dalguer, L. A.; Mai, Paul Martin ( 0000-0002-9744-4964 )
Abstract:
Large dynamic stresses near earthquake rupture fronts may induce an inelastic response of the surrounding materials, leading to increased energy absorption that may affect dynamic rupture. We systematically investigate the effects of off-fault plastic energy dissipation in 2-D in-plane dynamic rupture simulations under velocity-and-state-dependent friction with severe weakening at high slip velocity. We find that plasticity does not alter the nature of the transitions between different rupture styles (decaying versus growing, pulse-like versus crack-like, and subshear versus supershear ruptures) but increases their required background stress and nucleation size. We systematically quantify the effect of amplitude and orientation of background shear stresses on the asymptotic properties of self-similar pulse-like ruptures: peak slip rate, rupture speed, healing front speed, slip gradient, and the relative contribution of plastic strain to seismic moment. Peak slip velocity and rupture speed remain bounded. From fracture mechanics arguments, we derive a nonlinear relation between their limiting values, appropriate also for crack-like and supershear ruptures. At low background stress, plasticity turns self-similar pulses into steady state pulses, for which plastic strain contributes significantly to the seismic moment. We find that the closeness to failure of the background stress state is an adequate predictor of rupture speed for relatively slow events. Our proposed relations between state of stress and earthquake source properties in the presence of off-fault plasticity may contribute to the improved interpretation of earthquake observations and to pseudodynamic source modeling for ground motion prediction.
KAUST Department:
Physical Sciences and Engineering (PSE) Division
Citation:
Source properties of dynamic rupture pulses with off-fault plasticity 2013, 118 (8):4117 Journal of Geophysical Research: Solid Earth
Publisher:
Wiley-Blackwell
Journal:
Journal of Geophysical Research: Solid Earth
Issue Date:
Aug-2013
DOI:
10.1002/jgrb.50213
Type:
Article
ISSN:
21699313
Additional Links:
http://doi.wiley.com/10.1002/jgrb.50213
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorGabriel, A.-A.en
dc.contributor.authorAmpuero, J.-P.en
dc.contributor.authorDalguer, L. A.en
dc.contributor.authorMai, Paul Martinen
dc.date.accessioned2015-05-04T16:27:26Zen
dc.date.available2015-05-04T16:27:26Zen
dc.date.issued2013-08en
dc.identifier.citationSource properties of dynamic rupture pulses with off-fault plasticity 2013, 118 (8):4117 Journal of Geophysical Research: Solid Earthen
dc.identifier.issn21699313en
dc.identifier.doi10.1002/jgrb.50213en
dc.identifier.urihttp://hdl.handle.net/10754/552165en
dc.description.abstractLarge dynamic stresses near earthquake rupture fronts may induce an inelastic response of the surrounding materials, leading to increased energy absorption that may affect dynamic rupture. We systematically investigate the effects of off-fault plastic energy dissipation in 2-D in-plane dynamic rupture simulations under velocity-and-state-dependent friction with severe weakening at high slip velocity. We find that plasticity does not alter the nature of the transitions between different rupture styles (decaying versus growing, pulse-like versus crack-like, and subshear versus supershear ruptures) but increases their required background stress and nucleation size. We systematically quantify the effect of amplitude and orientation of background shear stresses on the asymptotic properties of self-similar pulse-like ruptures: peak slip rate, rupture speed, healing front speed, slip gradient, and the relative contribution of plastic strain to seismic moment. Peak slip velocity and rupture speed remain bounded. From fracture mechanics arguments, we derive a nonlinear relation between their limiting values, appropriate also for crack-like and supershear ruptures. At low background stress, plasticity turns self-similar pulses into steady state pulses, for which plastic strain contributes significantly to the seismic moment. We find that the closeness to failure of the background stress state is an adequate predictor of rupture speed for relatively slow events. Our proposed relations between state of stress and earthquake source properties in the presence of off-fault plasticity may contribute to the improved interpretation of earthquake observations and to pseudodynamic source modeling for ground motion prediction.en
dc.publisherWiley-Blackwellen
dc.relation.urlhttp://doi.wiley.com/10.1002/jgrb.50213en
dc.rightsArchived with thanks to Journal of Geophysical Research: Solid Earthen
dc.titleSource properties of dynamic rupture pulses with off-fault plasticityen
dc.typeArticleen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.identifier.journalJournal of Geophysical Research: Solid Earthen
dc.eprint.versionPublisher's Version/PDFen
dc.contributor.institutionSeismological Laboratory; California Institute of Technology; Pasadena; California; USAen
dc.contributor.institutionSwiss Seismological Service; Swiss Federal Institute of Technology Zurich; Zurich; Switzerlanden
dc.contributor.institutionDepartment of Earth and Environmental Sciences, Ludwig- Maximilians-University, Munich, Germany.en
kaust.authorMai, Paul Martinen
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