RT Journal Article T1 U–Pb ages of detrital zircons from the Basal allochthonous units of NW Iberia:Provenance and paleoposition on the northern margin of Gondwana during theNeoproterozoic and Paleozoic A1 Díez Fernández, Rubén A1 Martínez Catalán, José Ramón A1 Gerdex, Axel A1 Abati Gómez, Jacobo A1 Arenas Martín, Ricardo A1 Fernández Suárez, Javier AB LA-ICP-MS U–Pb ages of detrital zircons from eight siliciclastic samples from the Basal units of the Variscanallochthonous complexes of NW Iberia are used to establish the maximum depositional age and provenance oftwo tectonically-stacked metasedimentary sequences deposited on the outermost margin of Gondwana, andsubsequently involved in the Rheic Ocean suture. Themaximumdepositional ages for the two sequences is latestNeoproterozoic and latest Cambrian, respectively. The age spectra are also used to discuss the paleoposition of theNWIberian basement on the continentalmargin of Gondwana prior to the opening of the Rheic Ocean, which istentatively placed in northern Africa, between the West African and Saharan cratons. Based on similarities anddifferenceswith age data fromtheNWIberian autochthon and other allochthonous terranes involved inthe Rheicsuture, the relative proportions of Mesoproterozoic zircons in both assemblages are proposed as markers ofproximity to the eastern part of the West African craton during late Neoproterozoic and late Cambrian. Thegeodynamic processes that took place along this part of Gondwana during the late Neoproterozoic, late Cambrianand Early Ordovician are discussed in the light of the LA-ICP-MS results, as well as the sedimentological record,magmatic evolution and plate tectonic setting ofNWIberia. These processes are linked to late Neoproterozoic andCambro-Ordovician subduction events beneath the northern Gondwanan margin. PB Elsevier Science B. V., Amsterdam SN 1342-937X YR 2010 FD 2010 LK https://hdl.handle.net/20.500.14352/42426 UL https://hdl.handle.net/20.500.14352/42426 LA eng DS Docta Complutense RD 3 may 2024