Utilize este identificador para referenciar este registo:
https://hdl.handle.net/1822/2060
Título: | Composição isotópica Sr-Nd de granitos subalcalinos ferro-potássicos: o maciço granítico de Peneda-Gerês (NW Península Ibérica) |
Autor(es): | Mendes, Anabela Carreira Dias, G. |
Palavras-chave: | Granite Isotope Variscan Geochemistry |
Data: | Jul-2003 |
Citação: | CONGRESSO IBÉRICO DE GEOQUÍMICA, 4, Coimbra, 2003 - Congresso Ibérico de Geoquímica : actas. [Coimbra : s.n., 2003?]. p. 93-95. |
Resumo(s): | The Peneda-Gerês granitic massif is a good example of a post-tectonic Variscan massif. The granites are dominantly of subalkaline Fe-K affinity. The integration of geological, mineralogical, chemical and isotopic data suggests that this massif is the result of the emplacement of at least three intrusive magmas (Gerês-Covas, Calvos and Paufito-Illa-Carris) that evolved independently. A comparative study with other late-Variscan subalkaline granites of Portugal and other regions reveals that the isotope composition is globally weakly evolved (Sri = 0.7030-0.7069; eNdi = -1.0 to -2.5). The origin of these magmas by partial fusion of lower crustal material or, instead, a mixture between a depleted mantle component and a crustal component is discussed. For the Calvos granite a lower crustal protolith seems most probable while, for the other granites, the interaction between mafic mantle-derived magmas and the continental crust is the scenario that best explains their characteristics. During the waning stages of the Variscan orogeny, mantle input was most probably considerable. |
Tipo: | Artigo em ata de conferência |
URI: | https://hdl.handle.net/1822/2060 |
Arbitragem científica: | yes |
Acesso: | Acesso aberto |
Aparece nas coleções: | CCT - Comunicações/Communications |
Ficheiros deste registo:
Ficheiro | Descrição | Tamanho | Formato | |
---|---|---|---|---|
CompIso.pdf | 39,78 kB | Adobe PDF | Ver/Abrir |