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http://hdl.handle.net/10773/13021
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DC Field | Value | Language |
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dc.contributor.author | Costa, M. M. | pt |
dc.contributor.author | Neiva, A. M. R. | pt |
dc.contributor.author | Azevedo, M. R. | pt |
dc.contributor.author | Corfu, F. | pt |
dc.date.accessioned | 2014-12-17T10:24:28Z | - |
dc.date.issued | 2014 | - |
dc.identifier.issn | 0024-4937 | pt |
dc.identifier.uri | http://hdl.handle.net/10773/13021 | - |
dc.description.abstract | The Variscan syntectonic granitoid plutons from the Aguiar da Beira region (central Portugal) were emplaced into metasediments of Late Proterozoic-Early Cambrian age during the last Variscan ductile tectonic event (D3), which is related to dextral and sinistral shearing. The older intrusion, with a U-Pb ID-TIMS zircon age of 321.8±2.0Ma, consists of porphyritic biotite granodiorite-granite with transitional I-S type geochemical signature, relatively low 87Sr/86Sr322 ratios (0.7070-0.7074), εNd322 values of -3.9 to -4.6 and whole-rock and zircon δ18O values of 10.6‰ and 8.0‰, respectively. By contrast, the younger intrusion is an S-type muscovite-biotite leucogranite, emplaced at 317.0±1.1Ma, showing more radiogenic 87Sr/86Sr317=0.7104-0.7146, lower εNd317 values of -7.7 to -8.7 and higher δ18O-wr=11.3‰ and δ18O-zr=9.5‰. The combined isotopic and geochemical evidence supports a lower crustal origin for the biotite granodiorite-granite, involving the anatexis of lower crustal metaigneous protoliths, and possible hybridization with mantle-derived magmas. A shallower origin, at mid crustal levels, from pure crustal derivation, through moderate degrees of partial melting of Proterozoic-Cambrian metasediments is proposed instead for the muscovite-biotite leucogranite. © 2014 Elsevier B.V. | pt |
dc.language.iso | eng | pt |
dc.publisher | Elsevier | pt |
dc.relation | FCT - PTDC/CTE-GIX/112561/2009 | pt |
dc.relation | FCT - SFRH/BD/2005/21410 | pt |
dc.rights | restrictedAccess | por |
dc.subject | Aguiar da Beira | pt |
dc.subject | Geochemistry | pt |
dc.subject | Iberian Massif | pt |
dc.subject | Sr-Nd-O isotopes | pt |
dc.subject | Syntectonic granitoids | pt |
dc.subject | Granitoid | pt |
dc.subject | Hercynian orogeny | pt |
dc.subject | Neodymium isotope | pt |
dc.subject | Oxygen isotope | pt |
dc.subject | Petrogenesis | pt |
dc.subject | Strontium isotope | pt |
dc.subject | Uranium-lead dating | pt |
dc.subject | Zircon | pt |
dc.subject | Portugal | pt |
dc.title | Distinct sources for syntectonic Variscan granitoids: insights from the Aguiar da Beira region, Central Portugal | pt |
dc.type | article | pt |
dc.peerreviewed | yes | pt |
ua.distribution | international | pt |
ua.event.title | Lithos | |
degois.publication.firstPage | 83 | pt |
degois.publication.lastPage | 98 | pt |
degois.publication.title | Lithos | pt |
degois.publication.volume | 196-197 | pt |
dc.date.embargo | 10000-01-01 | - |
dc.identifier.doi | 10.1016/j.lithos.2014.02.023 | pt |
Appears in Collections: | DGeo - Artigos |
Files in This Item:
File | Description | Size | Format | |
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1-s2.0-S0024493714000802-main.pdf | Documento principal | 4.09 MB | Adobe PDF |
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