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Early Variscan HP metamorphism in the western Iberian Allochthon—A 390 Ma U–Pb age for the Bragança eclogite (NW Portugal)

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Abstract

HP rocks (eclogites and granulites) occur in the upper unit of the western Iberian allochthonous complexes in Spain and Portugal. This HP metamorphism was considered as Early Variscan or Ordovician in Spain and Precambrian in Portugal. We have dated eclogites retrogressed into granulites in the Bragança massif in NE Portugal by U–Pb on rutile and zircon. The upper intercept of the discordia gives 390±4 Ma that we consider as the age of the HP/HT metamorphism.

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Acknowledgements

Reviews by Ch. Pin, and an anonymous reviewer are gratefully acknowledged.

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  1. F. Roger

    Present address: Laboratoire de Dynamique de la Lithosphère, UMR 5573-CNRS—Université Montpellier 2, place Eugène Bataillon, 34095, Montpellier cedex, France

Authors and Affiliations

  1. Laboratoire de Géochronologie et Tectonique, UMR 7578-CNRS—Université Paris VII-IPG Paris, 75252, Paris, France

    F. Roger

  2. Laboratoire de Dynamique de la Lithosphère, UMR 5573-CNRS—Université Montpellier 2, place Eugène Bataillon, 34095, Montpellier cedex, France

    Ph. Matte

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Roger, F., Matte, P. Early Variscan HP metamorphism in the western Iberian Allochthon—A 390 Ma U–Pb age for the Bragança eclogite (NW Portugal). Int J Earth Sci (Geol Rundsch) 94, 173–179 (2005). https://doi.org/10.1007/s00531-005-0466-3

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