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dc.contributor.authorCampos, Thomas Ferreira da Costapt_BR
dc.contributor.authorNeiva, Ana Margarida Ribeiropt_BR
dc.contributor.authorNardi, Lauro Valentim Stollpt_BR
dc.contributor.authorPereira, Luciano Schaeferpt_BR
dc.contributor.authorBonzanini, Leonardo Andre Fragapt_BR
dc.contributor.authorPetta, Reinaldo Antoniopt_BR
dc.contributor.authorMeyer, Franz Michaelpt_BR
dc.date.accessioned2010-05-20T04:16:23Zpt_BR
dc.date.issued2005pt_BR
dc.identifier.issn1518-2398pt_BR
dc.identifier.urihttp://hdl.handle.net/10183/22618pt_BR
dc.description.abstractThe petrography and chemistry of epidote and amphibole from the Rio Espinharas hybrid complex (REHC), northeastern Brazil are reported. The Rio Espinharas complex is composed of an intimate association of diorite to shoshonitic metaluminous quartzmonzonite to slightly peraluminous syenogranite. The epidote shows four textural relationships: three are primary and one is resulting from sub-solidus reaction. Euhedral epidote is dispersed and associated mainly with biotite and amphibole. In some cases euhedral crystals of the epidote contain allanite cores, which are subhedral to anhedral and constitute in average less than 20% of the whole grain. The contact between primary epidote and plagioclase is corroded, suggesting reaction with the host-magma. Secondary anhedral epidote is rare and results from plagioclase alteration. The preservation of magmatic epidote in granitic rocks emplaced in the upper crust is attributed to rapid magma ascent, which implies fast upward transport probably by dyking associated to shear zone. The REHC occurs between two transcurrent faults that impose an elongated shape, suggesting that magma filled fractures. The time of 14 years required for dissolution zones of 0.15 mm width of epidote on porphyritic quartz monzonite, corresponds to an average ascent rate of ≥ 700 m year-1 from 7.1 to 2.9 kbar.en
dc.format.mimetypeapplication/pdf
dc.language.isoporpt_BR
dc.relation.ispartofPesquisas em Geociências. Vol. 32, n.2 (2005), p.41-55pt_BR
dc.rightsOpen Accessen
dc.subjectMagmatic epidoteen
dc.subjectGranito : Neoproterozóicopt_BR
dc.subjectQuímica mineralpt_BR
dc.subjectAmphiboleen
dc.subjectNeoproterozoic graniteen
dc.subjectMineral chemistryen
dc.titleMagmatic epidote and amphibole from the Rio Espinharas hybrid complex, Northeastern Brazilpt_BR
dc.typeArtigo de periódicopt_BR
dc.identifier.nrb000545445pt_BR
dc.type.originNacionalpt_BR


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