Deformation of Indian Ocean lithosphere: Evidence for a highly nonlinear rheological law

Simple item page
dc.citation.journalTitleJournal of Geophysical Research: Solid Earthen_US
dc.contributor.authorGordon, Richard G.en_US
dc.contributor.authorHouseman, Gregory A.en_US
dc.date.accessioned2015-07-09T15:30:04Zen_US
dc.date.available2015-07-09T15:30:04Zen_US
dc.date.issued2015en_US
dc.description.abstractThe width of diffuse oceanic plate boundaries is determined by the rheology of oceanic lithosphere. Here we apply thin viscous sheet models, which have been successfully applied to deformation in several continental deforming zones, to investigate the deformation of oceanic lithosphere in the diffuse oceanic plate boundaries between the India, Capricorn, and Australia Plates. We apply kinematic boundary conditions based on the current motion between these plates. We neglect buoyancy forces due to plate thinning or thickening and assume that the thin viscous sheet has the same depth-integrated nonlinear viscosity coefficient everywhere. Our initial models have only one adjustable parameter, n, the power-law exponent, with n = 1, 3, 10, 30, and 100. The predicted width of the deforming zone decreases with increasing n, with n ≥ 30 explaining the observations. This n value is higher than has been estimated for continental lithosphere and suggests that more of the strength of oceanic lithosphere lies in layers deforming by faulting or by dislocation glide than for continental lithosphere. To obtain a stress field that better fits the distribution and type of earthquake focal mechanisms in the diffuse oceanic plate boundary, we add a second adjustable parameter, representing the effect of slab pull stretching the oceanic plate near the Sumatra Trench. We show that an average velocity increment on this boundary segment of 5 mm a−1 (relative to the average velocity of the India and Australia Plates) fits the observed distribution of fault types better than velocities of 3.3 mm a−1 or 10 mm a−1.en_US
dc.identifier.citationGordon, Richard G. and Houseman, Gregory A.. "Deformation of Indian Ocean lithosphere: Evidence for a highly nonlinear rheological law." <i>Journal of Geophysical Research: Solid Earth,</i> (2015) Wiley: http://dx.doi.org/10.1002/2015JB011993.en_US
dc.identifier.doihttp://dx.doi.org/10.1002/2015JB011993en_US
dc.identifier.urihttps://hdl.handle.net/1911/80856en_US
dc.language.isoengen_US
dc.publisherWileyen_US
dc.rightsArticle is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.en_US
dc.subject.keywordrheologyen_US
dc.subject.keywordIndian Oceanen_US
dc.subject.keywordoceanic lithosphereen_US
dc.subject.keyworddiffuse plate boundariesen_US
dc.subject.keywordstrain fieldsen_US
dc.subject.keywordIndo-Australian Plateen_US
dc.titleDeformation of Indian Ocean lithosphere: Evidence for a highly nonlinear rheological lawen_US
dc.typeJournal articleen_US
dc.type.dcmiTexten_US
dc.type.publicationpublisher versionen_US
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
jgrb51134.pdf
Size:
4.73 MB
Format:
Adobe Portable Document Format
Description:
Download
Collections
Faculty Publications
Earth, Environmental and Planetary Sciences Publications