U-Pb Zircon geochronology of the Cambro-Ordovician metagranites and metavolcanic rocks of central and NW Iberia

New U-Pb zircon data from metagranites and metavolcanic rocks of the Schist-Graywacke Complex Domain and the Schistose Domain of Galicia Tras-os-Montes Zone from central and NW Iberia contribute to constrain the timing of the Cambro-Ordovician magmatism from Central Iberian and Galicia Tras-os-Montes Zones which occurred between 498 and 462 Ma. The crystallization ages of the metagranites and metavolcanic rocks from the northern Schist-Graywacke Complex Domain are as follows: (a) in west Salamanca, 489 +/- A 5 Ma for Vitigudino, 486 +/- A 6 Ma for Fermoselle and 471 +/- A 7 Ma for Ledesma; (b) in northern Gredos, 498 +/- A 4 Ma for Castellanos, 492 +/- A 4 Ma for San Pelayo and 488 +/- A 3 Ma for Bercimuelle; (c) in Guadarrama, 490 +/- A 5 Ma for La Estacin I, 489 +/- A 9 Ma for La Caada, 484 +/- A 6 Ma for Vegas de Matute (leucocratic), 483 +/- A 6 Ma for El Cardoso, 482 +/- A 8 Ma for La Morcuera, 481 +/- A 9 Ma for Buitrago de Lozoya, 478 +/- A 7 Ma for La Hoya, 476 +/- A 5 Ma for Vegas de Matute (melanocratic), 475 +/- A 5 Ma for Riaza, 473 +/- A 8 Ma for La Estacin II and 462 +/- A 11 Ma for La Berzosa; and (d) in Toledo, 489 +/- A 7 Ma for Mohares and 480 +/- A 8 Ma for Polan. The crystallization ages of the metagranites from the Schistose Domain of Galicia Tras-os-Montes Zone are 497 +/- A 6 Ma for Laxe, 486 +/- A 8 Ma for San Mamede, 482 +/- A 7 Ma for Bangueses, 481 +/- A 5 Ma for Noia, 480 +/- A 10 for Rial de Sabucedo, 476 +/- A 9 Ma for Vilanova, 475 +/- A 6 Ma for Pontevedra, 470 +/- A 6 Ma for Cherpa and 462 +/- A 8 Ma for Bande. This magmatism is characterized by an average isotopic composition of (Sr-87/Sr-86)(485Ma) a parts per thousand 0.712, (epsilon(Nd))(485Ma) a parts per thousand -4.1 and (T-DM) a parts per thousand 1.62 Ga, and a high zircon inheritance, composed of Ediacaran-Early Cambrian (65 %) and, to a lesser extent, Cryogenian, Tonian, Mesoproterozoic, Orosirian and Archean pre-magmatic cores. Combining our geochronological and isotopic data with others of similar rocks from the European Variscan Belt, it may be deduced that Cambro-Ordovician magmas from this belt were mainly generated by partial melting of Ediacaran-Early Cambrian igneous rocks.