Detrital zircon ages and provenance of a Cambrian succession in the Sierra Albarrana Domain (SW Iberian Massif)

• Published in: Lithos 2022-01, Vol.408-409, p.106542, Article 106542
• Main Authors: Solís-Alulima, Byron, Abati, Jacobo, López-Carmona, Alicia, Gutiérrez-Alonso, Gabriel, Fernández-Suárez, Javier, Stockli, Daniel F.
• Format: Article
• Language: English
• Subjects: Cadomian orogen; Central-Iberian zone; Maximum depositational age (MDA); Sierra Albarrana domain; U-Pb geochronology
• ISSN: 0024-4937; 1872-6143
• DOI: 10.1016/j.lithos.2021.106542

This study presents the first U-Pb geochronological data on detrital zircon grains from the metasedimentary successions of the Sierra Albarrana Domain (SW Iberian Massif) obtained by SHRIMP and LA-ICP-MS. We provide new information on the Maximum Depositional Ages (MDA) during the middle Cambrian through a systematic study, together with age comparisons of the successions, using Kernel Density Estimates (KDE) diagrams, Cumulative Age Distributions (CADs) and the Kolmogorov–Smirnov (K-S) test. On the other hand, the U-Pb zircon data presented in this study have been compared with all the existing data from detrital zircon grains in Neoproterozoic and Cambrian rocks of the Iberian Massif (20 samples, 2706 U–Pb zircon ages). For the comparison, in addition to the KDEs, CADs and K-S test, we apply 3D multidimensional scaling techniques (3D-MDS). The results, together with the geochemical and isotopic characterisation from previous studies, suggest that this domain is likely to be part of the autochthonous section of the Central Iberian Zone (CIZ). Zircon age patterns indicate a probable sedimentary provenance from the Saharan Metacraton with, or without, minor input from the Tuareg Shield. The most important local detrital source corresponds to Cadomian magmatism developed during a magmatic event (535–515 Ma) followed by back-arc extension and early Paleozoic rifting (535–460 Ma). The remaining Mesoproterozoic, Paleoproterozoic and Archean zircon grains would have been provided by the Paleoproterozoic basement and/or the older continental crust recycled in the western sections of the Gondwana margin. [Display omitted]