Upper-mantle seismic anisotropy from SKS splitting in the South American stable platform: A test of asthenospheric flow models beneath the lithosphere

Página do item simplificado
dc.contributor.authorAssumpcao, Marcelo
dc.contributor.authorGuarido, Marcelo
dc.contributor.authorvan der Lee, Suzan
dc.contributor.authorDourado, Joao Carlos [UNESP]
dc.contributor.institutionUniversidade de São Paulo (USP)
dc.contributor.institutionNorthwestern University (NU)
dc.contributor.institutionUniversidade Estadual Paulista (Unesp)
dc.date.accessioned2013-09-30T18:51:14Z
dc.date.accessioned2014-05-20T14:16:59Z
dc.date.available2013-09-30T18:51:14Z
dc.date.available2014-05-20T14:16:59Z
dc.date.issued2011-04-01
dc.description.abstractUpper-mantle seismic anisotropy has been extensively used to infer both present and past deformation processes at lithospheric and asthenospheric depths. Analysis of shear-wave splitting (mainly from core-refracted SKS phases) provides information regarding upper-mantle anisotropy. We present average measurements of fast-polarization directions at 21 new sites in poorly sampled regions of intra-plate South America, such as northern and northeastern Brazil. Despite sparse data coverage for the South American stable platform, consistent orientations are observed over hundreds of kilometers. Over most of the continent, the fast-polarization direction tends to be close to the absolute plate motion direction given by the hotspot reference model HS3-NUVEL-1A. A previous global comparison of the SKS fast-polarization directions with flow models of the upper mantle showed relatively poor correlation on the continents, which was interpreted as evidence for a large contribution of "frozen" anisotropy in the lithosphere. For the South American plate, our data indicate that one of the reasons for the poor correlation may have been the relatively coarse model of lithospheric thicknesses. We suggest that improved models of upper-mantle flow that are based on more detailed lithospheric thicknesses in South America may help to explain most of the observed anisotropy patterns.en
dc.description.affiliationUniv São Paulo, Inst Astron Geophys & Atmospher Sci, BR-05508090 São Paulo, Brazil
dc.description.affiliationNorthwestern Univ, Dept Earth & Planetary Sci, Evanston, IL 60208 USA
dc.description.affiliationState Univ São Paulo UNESP, Inst Geosci IGCE, BR-13506900 Rio Claro, SP, Brazil
dc.description.affiliationUnespState Univ São Paulo UNESP, Inst Geosci IGCE, BR-13506900 Rio Claro, SP, Brazil
dc.description.sponsorshipConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
dc.description.sponsorshipFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
dc.description.sponsorshipETH-Z (Federal Institute of Technology, Zurich, Switzerland), Switzerland
dc.description.sponsorshipIdCNPq: 308861/2006-0
dc.description.sponsorshipIdFAPESP: 01/06066-6
dc.description.sponsorshipIdFAPESP: 02/00244-2
dc.description.sponsorshipIdFAPESP: 05/51035-2
dc.description.sponsorshipIdETH-Z (Federal Institute of Technology, Zurich, Switzerland), Switzerland: 0-20990-02
dc.format.extent173-180
dc.identifierhttp://dx.doi.org/10.1130/L99.1
dc.identifier.citationLithosphere. Boulder: Geological Soc Amer, Inc, v. 3, n. 2, p. 173-180, 2011.
dc.identifier.doi10.1130/L99.1
dc.identifier.issn1941-8264
dc.identifier.urihttp://hdl.handle.net/11449/25095
dc.identifier.wosWOS:000288848000008
dc.language.isoeng
dc.publisherGeological Soc America
dc.relation.ispartofLithosphere
dc.relation.ispartofjcr2.766
dc.relation.ispartofsjr1,892
dc.rights.accessRightsAcesso restrito
dc.sourceWeb of Science
dc.titleUpper-mantle seismic anisotropy from SKS splitting in the South American stable platform: A test of asthenospheric flow models beneath the lithosphereen
dc.typeArtigo
dcterms.rightsHolderGeological Soc Amer, Inc
unesp.campusUniversidade Estadual Paulista (Unesp), Instituto de Geociências e Ciências Exatas, Rio Claropt

Arquivos

Licença do Pacote
Agora exibindo 1 - 2 de 2
Nenhuma Miniatura disponível
Nome:
license.txt
Tamanho:
1.71 KB
Formato:
Item-specific license agreed upon to submission
Descrição:
Nenhuma Miniatura disponível
Nome:
license.txt
Tamanho:
1.71 KB
Formato:
Item-specific license agreed upon to submission
Descrição:

Coleções

Artigos - Geologia Aplicada - IGCE