Options
Gaete, R.
Loading...
Preferred name
Gaete, R.
2 results
Now showing 1 - 2 of 2
- PublicationOpen AccessChronostratigraphic synthesis of the latest Cretaceous dinosaur turnover in south-western Europe(2019)
; ; ; ; ; ; ; ; ; ; ; ; ;; ; ; ;In south-western Europe, the uppermost Cretaceous continental deposits in the different sedimentary basins of Iberia (Portugal and north and central Spain), the Pyrenees (Spain and France) as well as Languedoc and Provence (southern France) provide one of the few terrestrial records that allow a comprehensive study of the Campanian-Maastrichtian dinosaur assemblages. For the last years the southern Pyrenees has been the target of intense geological, palaeontological and geochronological research. Hundreds of fossil localities are now framed in high-resolution lithological sections. The succession of these sites, most of them located in the Tremp Syncline, is based on the physical correlation of rock bodies, as permitted by the general outcropping conditions. Outside this syncline, correlation is supported by geochronologic and biostratigraphic data (mainly magnetostratigraphy and planktic foraminifera biostratigraphy). The integration of the entire dataset sheds new light on the Maastrichtian dinosaur turnover, characterized by a shift from a sauropod-dominated to a hadrosauroid-dominated faunal assemblage. This turnover was progressive and involved immigrants from North America, Eurasia and Gondwana, which probably reached the study area after a sea level drop. This faunal change was mainly triggered by the arrival of lambeosaurine hadrosauroids, a group that rapidly displaced the rest of the herbivorous clades of the region. Some of the extinction events suffered by the “pre-turnover” faunas during the Maastrichtian coincide with marine isotopic and sea-level drop events, suggesting that faunal competition was not the only cause of the observed changes in dinosaur composition. Despite this faunal replacement, the resulting ecosystem after the turnover shows no major loss of biodiversity before the Cretaceous-Paleogene extinction event.160 288 - PublicationRestrictedThe diversity of sauropod dinosaurs and their first taxonomic succession from the latest Cretaceous of southwestern Europe: Clues to demise and extinction(2012-09-15)
; ; ; ; ; ; ; ; ; ;Vila, B.; Paleontología, Facultad de Ciencias, Universidad de Zaragoza, 50009 Zaragoza, Spain ;Galobart, À.; Institut Català de Paleontologia Miquel Crusafont, Carrer Escola Industrial, 23, 08201 Sabadell, Barcelona, Catalonia, Spain ;Canudo, J. I.; Paleontología, Facultad de Ciencias, Universidad de Zaragoza, 50009 Zaragoza, Spain ;Le Loeuff, J.; Musée des Dinosaures, 11260 Espéraza, France ;Dinarès-Turell, J.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Riera, V.; Departament de Geologia, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Catalonia, Spain ;Oms, O.; Departament de Geologia, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Catalonia, Spain ;Tortosa, T.; Muséum d'Histoire Naturelle d'Aix-en-Provence, 13100 Aix-en-Provence, France ;Gaete, R.; Museu de la Conca Dellà, C/ del Museu 4, 25650 Isona i Conca Dellà, Lleida, Catalonia, Spain; ; ; ; ; ; ; ; Southwestern Europe is a key setting to evaluate the diversity of non-avian dinosaurs before the end of the Cretaceous (below the K–Pg boundary). The ancient Ibero-Armorican Island, encompassing the current regions of North-East Iberia and South France, provides a substantial record of sauropod fossils. The study of multiple sauropod femora from localities where upper Campanian to uppermost Maastrichtian successions are both exposed, together with the integration of the information gathered from previously known localities has allowed the biodiversity of sauropods to be reassessed within a precise and clear chronostratigraphic framework. From the studied sample several titanosaur forms have been distinguished including a gracile and small-sized titanosaur (Lirainosaurus astibiae), a robust medium-sized titanosaur (Ampelosaurus atacis), a gracile medium-sized titanosaur (Atsinganosaurus velauciensis), and five other indeterminate but distinct titanosaurs, which span the late Campanian through the entire Maastrichtian. The youngest of these occurs in the uppermost part of palaeomagnetic chron C30n in the latest Maastrichtian (~0.4–1 Ma before the K–Pg boundary), representing the youngest sauropod yet documented in Eurasia. The pattern of diversity on the Ibero-Armorican Island rules out a decline in sauropod diversity at the very end of the Cretaceous. As with other regions during the late Cretaceous, the abundance and quality of the sauropod fossil record is probably influenced by multiple biases (sampling, ecological, and environmental).299 28