Tectonic setting and U/Pb zircon dating of the plutonic Socorro Complex in the Transpressive Rio Paraíba do Sul Shear Belt, SE Brazil

dc.contributor.authorEbert, H. D. [UNESP]
dc.contributor.authorChemale, F.
dc.contributor.authorBabinski, M.
dc.contributor.authorArtur, A. C. [UNESP]
dc.contributor.authorVan Schmus, W. R.
dc.contributor.institutionUniversidade Estadual Paulista (Unesp)
dc.contributor.institutionUniv. Federal do Rio Grande do Sul
dc.contributor.institutionUniversidade de São Paulo (USP)
dc.contributor.institutionUniversity of Kansas (KU)
dc.contributor.institutionUniv. Fed. do Rio Grande do Sul -RS
dc.date.accessioned2014-05-27T11:18:05Z
dc.date.available2014-05-27T11:18:05Z
dc.date.issued1996-06-01
dc.description.abstractThe Precambrian Rio Paraíba do Sul Shear Belt comprises a 200-km-wide anastomosing network of NE-SW trending ductile shear zones extending over 1000 km of the southeastern coast of Brazil. Granulitic, gneissic-migmatitic, and granitoid terrains as well as low- to medium-grade metavolcanosedimentary sequences are included within it. These rocks were affected by strong contractional, tangential tectonics, due to west-northwestward oblique convergence of continental blocks. Subsequent transpressional tectonics accomodated large dextral, orogen-parallel movements and shortening. The plutonic Socorro Complex is one of many deformed granites with a foliation subparallel to that of the shear belt and exposes crosscutting relationships between its tectonic, magmatic, and metamorphic structures. These relationships point to a continuous magmatic evolution related to regional thrusts and strike slip, ductile shear zones. The tectonic and magmatic structural features of the Serra do Lopo Granite provide a model of emplacement by sheeting along shear zones during coeval strike-slip and cross shortening of country rocks. Geochronological data indicate that the main igneous activity of Socorro Complex spanned at least 55 million years, from the late stage of the northwestward ductile thrusting (650 Ma), through right-lateral strike slip (595 Ma) deformation. The country rocks yield discordant age data, which reflect a strong imprint of the Transamazonian tectono-metamorphic event (1.9 to 2.0 Ma). We propose a model for the origin of calcalkaline granites of the Ribeira Belt by partial melting of the lower crust with small contributions of the lithospheric mantle during transpressional thickening of plate margins, which were bounded by deep shear zones. The transpressional regime also seems to have focused granite migration from deeper into higher crustal levels along these shear zones.en
dc.description.affiliationInst. de Geociencias e Cie. Exatas Universidade Estadual Paulista, Rio Claro-SP
dc.description.affiliationInstituto de Geociências Univ. Federal do Rio Grande do Sul, Porto Alegre-RS
dc.description.affiliationInstituto de Geociências Universidade de São Paulo, São Paulo-SP
dc.description.affiliationDepartment of Geology University of Kansas, Lawrence, KS
dc.description.affiliationInst. de Geociencias e Cie. Exatas Univ. Estadual Paulista, Rio C., PO Box 178, 13506-900 Rio Claro-SP
dc.description.affiliationInstituto de Geociências Universidade de São Paulo, Caixa Poslal 11348, 05422-970 São Paulo-SP
dc.description.affiliationInstitute de Geociências Univ. Fed. do Rio Grande do Sul -RS, PO Box 15006, 91501-970, Porto Alegre-RS
dc.description.affiliationDepartment of Geology Kansas Univ. Center for Research University of Kansas, Lawrence, KS 66045
dc.description.affiliationUnespInst. de Geociencias e Cie. Exatas Universidade Estadual Paulista, Rio Claro-SP
dc.format.extent688-699
dc.identifierhttp://dx.doi.org/10.1029/95TC03247
dc.identifier.citationTectonics, v. 15, n. 3, p. 688-699, 1996.
dc.identifier.doi10.1029/95TC03247
dc.identifier.issn0278-7407
dc.identifier.scopus2-s2.0-0030481198
dc.identifier.urihttp://hdl.handle.net/11449/64792
dc.identifier.wosWOS:A1996UU42800010
dc.language.isoeng
dc.relation.ispartofTectonics
dc.relation.ispartofjcr3.583
dc.relation.ispartofsjr2,544
dc.rights.accessRightsAcesso restrito
dc.sourceScopus
dc.subjectemplacement mechanism
dc.subjectgranite
dc.subjectmagmatism
dc.subjectPrecambrian
dc.subjectshear zone
dc.subjectsheeting
dc.subjecttectonics
dc.subjectBrazil, Rio Paraiba do Sul Shear Belt
dc.titleTectonic setting and U/Pb zircon dating of the plutonic Socorro Complex in the Transpressive Rio Paraíba do Sul Shear Belt, SE Brazilen
dc.typeArtigo
dcterms.licensehttp://olabout.wiley.com/WileyCDA/Section/id-406071.html
unesp.author.orcid0000-0003-2444-2404[3]

Arquivos

Coleções