RT Journal Article
T1 Detrital zircons from the Ordovician rocks of the Pyrenees: Geochronological constraints and provenance
A1 Margalef, Aina
A1 Castiñeiras García, Pedro
A1 Casas Tuset, Josep María
A1 Navidad Fernández De La Cruz, Marina
A1 Liesa Torre Marín, Montserrat
A1 Linnemann, Ulf
A1 Hofmann, Mandy
A1 Gärtner, Andreas
AB The first LA-ICP-MS U–Pb detrital zircon ages from quartzites located below (three samples) and above (one sample) the Upper Ordovician unconformity in the Central Pyrenees (the Rabassa Dome, Andorra) were investigated. The maximum depositional age for the Jújols Group, below the unconformity, based on the youngest detrital zircon population, is around 475 Ma (Early Ordovician), whereas for the Bar Quartzite Fm., above the unconformity, the presence of only two zircons of 442 and 443 Ma precludes obtaining a precise maximum sedimentation age. A time gap of ~20 million years for the Upper Ordovician unconformity in the Pyrenees can be proposed, similar to that of the Sardic unconformity in Sardinia. The similar age patterns obtained on both sides of the Upper Ordovician unconformity suggest that there was no change in the source area of these series, while the absence of aMiddle Ordovician age population may be due to a lack of sedimentation at that time. The four study samples present very similar U–Pb age patterns: the main age populations correspond to Neoproterozoic (Ediacarian–Cryogenian, ca. 550–750 Ma); Grenvillian (Tonian–Stenian, ca. 850–1100 Ma); Paleoproterozoic (Orosirian, ca.1900–2100 Ma) and Neoarchean (ca. 2500–2650 Ma). The similarity with the Sardinian age distribution suggests that these two terranes could share the same source area and that they were paleogeographically close in Ordovician times in front of the Arabian–Nubian Shield.
PB Elsevier
SN 0040-1951
YR 2016
FD 2016-03-16
LK https://hdl.handle.net/20.500.14352/23186
UL https://hdl.handle.net/20.500.14352/23186
LA eng
NO Ministerio de Economía y Competitividad (MINECO)
DS Docta Complutense
RD 7 abr 2025