Evolución metamórfica de los esquistos de AP/BT de Ceán (Unidad de Malpica-Tui, NW del Macizo Ibérico)
Metapelitic schists from the upper structural levels of the Malpica-Tui Unit contain an initial blueschist facies mineral assemblage that appears mainly preserved as micro-inclusions in garnet, albite and chloritoid porphiroblasts defining a S1 foliation. The main foliation (S2) represents an evolut...
| Autores: | , , |
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| Tipo de documento: | artigo |
| Data de publicação: | 2007 |
| País: | España |
| Recursos: | Universidad de Huelva (UHU) |
| Repositório: | Arias Montano. Repositorio Institucional de la Universidad de Huelva |
| Idioma: | espanhol |
| OAI Identifier: | oai:ariasmontano.uhu.es:10272/8359 |
| Acesso em linha: | http://hdl.handle.net/10272/8359 |
| Access Level: | Acceso aberto |
| Palavra-chave: | Variscan Belt Allochthonous Complexes Malpica-Tui Unit Blueschists facies Thermobarometry |
| Resumo: | Metapelitic schists from the upper structural levels of the Malpica-Tui Unit contain an initial blueschist facies mineral assemblage that appears mainly preserved as micro-inclusions in garnet, albite and chloritoid porphiroblasts defining a S1 foliation. The main foliation (S2) represents an evolution of the S1 to slightly higher temperature and lower pressure, but it is still developed in blueschist facies conditions. Post-S2 deformations include restricted development of spaced C’ shear bands, tight and straight D3 folds and a later gentle subhorizontal crenulation formed in greenschists facies conditions. Garnet-phengite thermometry and GRIPS and GASP barometry calculations, using micro-inclusion compositions, indicate peak conditions around P=19-22 Kbar and T=430-500 ºC. The same calculations using the S2 fabric minerals yield approximate values of P=16-19 Kbar and T=440-515 ºC |
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