Portail de Conférences / Conference Portal, JK2018

Font Size: 
Tracking dinosaurs across the Jurassic-Cretaceous boundary
Christian Andreas Meyer, Matteo Belvedere

Building: Muséum d'Histoire Naturelle de Genève
Room: Amphithéâtre
Date: 2018-12-05 02:30 PM – 02:50 PM
Last modified: 2018-11-23

Abstract


In the late Jurassic (Kimmeridgian/Tithonian) dinosaur tracks occur in a variety of depositional environments from tidal flats to lacustrine as well as fluvial settings. These two stages include sites from Germany, Switzerland, France, Croatia, Spain and Portugal. They show tracks and trackways of sauropods (diplodocids, titanosaurs), theropods (megalosaurids), thyreophorans (stegosaurs) as well as those from ornithopods (camptosaurids), with a preference of sauropod/theropod assemblages (Brotnopodus Ichnofacies) in tidal flat environments.

In the early Cretaceous (?Berriasian/Valanginian) dinosaur tracksites are mostly found in fluvial and lacustrine settings (Wealden Facies), they seem to be almost absent in Tethysian tidal flat settings. It includes sites in England, Northern Germany as well as Spain, the latter region is the most prolific. They yield tracks and trackways of theropods (Megalosaurids, Dromaeosaurids), ornithopods (Iguandontids) and some rare sauropods.

Although a shift in more continental settings can be detected, there is no change in the diversity of dinosaurs groups represented by tracks. Whereas in the Late Jurassic there is a predominance of the Brontopodus Ichnofacies a change to a dominance of the Caririchnium Ichnofacies can be observed in the Early Cretaceous. This change is due to the appearance of new dinosaur groups as well as a change from more arid to more humid conditions and tectonics resulting in large deltaic settings in Northern Europe, Southern France and the Iberian Meseta.