The seismic cycle at subduction thrusts: 2. Dynamic implications of geodynamic simulations validated with laboratory models

Handle URI:
http://hdl.handle.net/10754/552151
Title:
The seismic cycle at subduction thrusts: 2. Dynamic implications of geodynamic simulations validated with laboratory models
Authors:
van Dinther, Y.; Gerya, T. V.; Dalguer, L. A.; Corbi, F.; Funiciello, F.; Mai, Paul Martin ( 0000-0002-9744-4964 )
Abstract:
The physics governing the seismic cycle at seismically active subduction zones remains poorly understood due to restricted direct observations in time and space. To investigate subduction zone dynamics and associated interplate seismicity, we validate a continuum, visco-elasto-plastic numerical model with a new laboratory approach (Paper 1). The analogous laboratory setup includes a visco-elastic gelatin wedge underthrusted by a rigid plate with defined velocity-weakening and -strengthening regions. Our geodynamic simulation approach includes velocity-weakening friction to spontaneously generate a series of fast frictional instabilities that correspond to analog earthquakes. A match between numerical and laboratory source parameters is obtained when velocity-strengthening is applied in the aseismic regions to stabilize the rupture. Spontaneous evolution of absolute stresses leads to nucleation by coalescence of neighboring patches, mainly occurring at evolving asperities near the seismogenic zone limits. Consequently, a crack-, or occasionally even pulse-like, rupture propagates toward the opposite side of the seismogenic zone by increasing stresses ahead of its rupture front, until it arrests on a barrier. The resulting surface displacements qualitatively agree with geodetic observations and show landward and, from near the downdip limit, upward interseismic motions. These are rebound and reversed coseismically. This slip increases adjacent stresses, which are relaxed postseismically by afterslip and thereby produce persistent seaward motions. The wide range of observed physical phenomena, including back-propagation and repeated slip, and the agreement with laboratory results demonstrate that visco-elasto-plastic geodynamic models with rate-dependent friction form a new tool that can greatly contribute to our understanding of the seismic cycle at subduction zones.
KAUST Department:
Physical Sciences and Engineering (PSE) Division
Citation:
The seismic cycle at subduction thrusts: 2. Dynamic implications of geodynamic simulations validated with laboratory models 2013, 118 (4):1502 Journal of Geophysical Research: Solid Earth
Publisher:
Wiley-Blackwell
Journal:
Journal of Geophysical Research: Solid Earth
Issue Date:
Apr-2013
DOI:
10.1029/2012JB009479
Type:
Article
ISSN:
21699313
Additional Links:
http://doi.wiley.com/10.1029/2012JB009479
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorvan Dinther, Y.en
dc.contributor.authorGerya, T. V.en
dc.contributor.authorDalguer, L. A.en
dc.contributor.authorCorbi, F.en
dc.contributor.authorFuniciello, F.en
dc.contributor.authorMai, Paul Martinen
dc.date.accessioned2015-05-04T16:26:13Zen
dc.date.available2015-05-04T16:26:13Zen
dc.date.issued2013-04en
dc.identifier.citationThe seismic cycle at subduction thrusts: 2. Dynamic implications of geodynamic simulations validated with laboratory models 2013, 118 (4):1502 Journal of Geophysical Research: Solid Earthen
dc.identifier.issn21699313en
dc.identifier.doi10.1029/2012JB009479en
dc.identifier.urihttp://hdl.handle.net/10754/552151en
dc.description.abstractThe physics governing the seismic cycle at seismically active subduction zones remains poorly understood due to restricted direct observations in time and space. To investigate subduction zone dynamics and associated interplate seismicity, we validate a continuum, visco-elasto-plastic numerical model with a new laboratory approach (Paper 1). The analogous laboratory setup includes a visco-elastic gelatin wedge underthrusted by a rigid plate with defined velocity-weakening and -strengthening regions. Our geodynamic simulation approach includes velocity-weakening friction to spontaneously generate a series of fast frictional instabilities that correspond to analog earthquakes. A match between numerical and laboratory source parameters is obtained when velocity-strengthening is applied in the aseismic regions to stabilize the rupture. Spontaneous evolution of absolute stresses leads to nucleation by coalescence of neighboring patches, mainly occurring at evolving asperities near the seismogenic zone limits. Consequently, a crack-, or occasionally even pulse-like, rupture propagates toward the opposite side of the seismogenic zone by increasing stresses ahead of its rupture front, until it arrests on a barrier. The resulting surface displacements qualitatively agree with geodetic observations and show landward and, from near the downdip limit, upward interseismic motions. These are rebound and reversed coseismically. This slip increases adjacent stresses, which are relaxed postseismically by afterslip and thereby produce persistent seaward motions. The wide range of observed physical phenomena, including back-propagation and repeated slip, and the agreement with laboratory results demonstrate that visco-elasto-plastic geodynamic models with rate-dependent friction form a new tool that can greatly contribute to our understanding of the seismic cycle at subduction zones.en
dc.publisherWiley-Blackwellen
dc.relation.urlhttp://doi.wiley.com/10.1029/2012JB009479en
dc.rightsArchived with thanks to Journal of Geophysical Research: Solid Earthen
dc.titleThe seismic cycle at subduction thrusts: 2. Dynamic implications of geodynamic simulations validated with laboratory modelsen
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.institutionInstitute of Geophysics; ETH Zürich; Zürich; Switzerlanden
dc.contributor.institutionSwiss Seismological Service; ETH Zürich; Zürich; Switzerlanden
dc.contributor.institutionLET-Laboratory of Experimental Tectonics, Univ. “Roma Tre”; Roma; Italyen
dc.contributor.institutionLET-Laboratory of Experimental Tectonics, Univ. “Roma Tre”; Roma; Italyen
kaust.authorMai, Paul Martinen
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