Exhumation of high-pressure rocks in northern Gondwana during the Early Carboniferours (Coimbra–Cordoba shear zone, SW Iberian Massif): Tectonothermal analysis and U–Th–Pb SHRIMP in-situ zircon geochronology

North-Gondwana assembly, break-up and paleogeography: U–Pb isotope evidence from detrital and igneous zircons of Ediacaran and Cambrian rocks of SW Iberia

“…The defined age clusters set suggest provenance from sources near or at the North-Gondwana margin, comprising three main zircon-forming events related to a long-lived Neoproterozoic magmatism: 1) c. 850-700 Ma (PanAfrican suture); 2) c. 700-635 Ma (early Cadomian arc); and 3) c. 635-545 Ma (late Cadomian arc) (Pereira et al, 2012). The U-Pb ages obtained in the Estremoz Anticline agree with recently published data deriving from other regions of the Ossa-Morena Zone Pereira et al, 2008Pereira et al, , 2010aPereira et al, , 2010bPereira et al, , 2011 but, also surprisingly with the SW Central-Iberian Zone (Pereira et al, 2012) in SW Iberia, and overlap the time intervals assigned to Avalonia (c. 730-570 Ma;Murphy et al, 2008;Nance et al, 2008 and references therein), Cadomia (c. 850-550 Ma;755-745 Ma and c. 625-570 Ma;Fernández-Suárez et al, 2002;Nagy et al, 2002;Samson et al, 2003;and Nance et al, 2008 and references therein), Bohemia (c. 790-560 Ma;Linnemann et al, 2007Linnemann et al, , 2008 and AntiAtlas (c. 755-700 Ma and c. 640-560 Ma;D'Lemos et al, 2006;Ennih and Liégeois, 2008;Abati et al, 2010) zircon-forming events recorded in the West African Craton (Fig. 9).…”

“…These spectra of Proterozoic detrital zircon ages are similar to other peri-Gondwana correlatives with West African Craton provenance (Linnemann et al, 2007Nance et al, 2008 and references therein;Zeh and Gerdes, 2010;Pereira et al, 2008Pereira et al, , 2010aPereira et al, , 2010bPereira et al, , 2011Pereira et al, , 2012.…”

Evolution of the Corsica–Sardinia Batholith and late-orogenic shearing of the Variscides

“…9). A model of crustal-scale shearing is fit to explain the observed offsets of the orogenic structure, as well as most features of late Carboniferous paleo-geographic models for the south Variscan chain (Matte, 2001;Pereira et al, 2010). In contrast, lower Permian U2 and U3 plutons show a completely different architecture consistent with orogen-perpendicular extension (Gattacceca et al, 2004).…”

SHRIMP U–Pb zircon dating of the Valencia del Ventoso plutonic complex, Ossa-Morena Zone, SW Iberia: Early Carboniferous intra-orogenic extension-related ‘calc-alkaline’ magmatism

“…1B). The contact with the Central Iberian Zone, to the north, is marked by the Badajoz-Córdoba fault, interpreted as a major Variscan intra-continental shear zone (Burg et al, 1981;Azor et al, 1994;Gómez-Pugnaire et al, 2003;Simancas et al, 2005;Pereira et al, 2007Pereira et al, , 2009Pereira et al, , 2010aPereira et al, , 2010bPereira et al, , 2012a (Fig. 1).…”