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Saint-Sauveur-en-Rue, France

Allain R.,CNRS Center for Research on Palaeobiodiversity and Palaeoenvironments | Vullo R.,CNRS Geosciences Laboratory of Rennes | Le Loeuff J.,Musee des Dinosaures | Tournepiche J.-F.,Musee dAngouleme
Geologica Acta

Early Cretaceous ornithomimosaurian theropod dinosaurs have been reported from various localities in Asia, whereas they remain poorly represented and extremely rare in North America, Africa and Europe. So far, the only known European ornithomimosaur is Pelecanimimus from the Barremian of Spain. The recent discovery in southwestern France of the Angeac bone bed, which has yielded several hundred ornithomimosaur bones, sheds new light on the ornithomimosaurian fossil record. Based on this new material, we re-evaluate here the systematic position of various isolated theropod bones from the Wealden of England, including historical taxa of uncertain affinities. Based on a unique combination of derived characters, Thecocoelurus and Valdoraptor are linked to the Angeac taxon but are considered to be nomina dubia. Valdoraptor from the Valanginian of West Sussex appears to be the oldest known ornithomimosaur together with the contemporaneous Nqwebasaurus from South Africa. Ornithomimosaurs were a common component of the Early Cretaceous European dinosaur fauna. Their presence in Spain, France and England further strengthens the palaeobiogeographic affinities of the European fossil biota with that of Asia during this period. Source

Neraudeau D.,CNRS Geosciences Laboratory of Rennes | Allain R.,CNRS Center for Research on Palaeobiodiversity and Palaeoenvironments | Ballevre M.,CNRS Geosciences Laboratory of Rennes | Batten D.J.,University of Manchester | And 19 more authors.
Cretaceous Research

This paper provides the sedimentological, palaeontological and biostratigraphical characteristics of a newly discovered lignite-bearing sedimentary succession in western France. The lignitic bed, which is reminiscent of some Wealden facies in southern England, is located in Angeac in the Charentes region. The plant remains occur as three-dimensionally preserved mesofossils (cuticles, charred ferns and seeds, cones and twigs) and larger pieces of wood. The deposits contain variable amounts of such material and at one horizon in particular, an outstanding accumulation of dinosaur teeth and bones. Among the vertebrate remains are the longest sauropod femur (ca. 220. cm) yet found and bones representing an ornithomimosaur herd of at least eight individuals. The palynomorph content of the clay associated with the bones and lignitic material indicates a Hauterivian-Barremian age. The abundance in the fossil assemblage of freshwater unionoid bivalves, some preserved in life position, the presence of freshwater algae, and the scarcity of brackish or marine species indicate that the depositional environment was a swamp only very occasionally connected to the sea. The forest bordering the swamp was dominated by cheirolepidiaceous trees co-occurring with a diverse assemblage of ferns. © 2012 . Source

Puymerail L.,French National Center for Scientific Research | Puymerail L.,French Natural History Museum | Volpato V.,Senckenberg Institute | Debenath A.,French Natural History Museum | And 5 more authors.
Comptes Rendus - Palevol

We describe a human partial femoral shaft discovered during speleological exploration of the "grotte de la Tour", near the prehistoric site of La Chaise-de-Vouthon (Charente, France). The context of discovery is compatible with a hyena den deposit; the associated mammal assemblage suggests a preliminary chronological attribution to MIS 3. Combined information from its outer morphology, cross-sectional geometric properties, and from the high-resolution 3D imaging and quantitative analysis of its inner structural organization shows that this specimen (CDV-Tour 1) is from an adult Neanderthal individual, more likely a male. © 2012 Académie des sciences. Source

El Albani A.,University of Poitiers | Meunier A.,University of Poitiers | Macchiarelli R.,French Natural History Museum | Macchiarelli R.,University of Poitiers | And 2 more authors.
Quaternary International

The four stratigraphic units of the Late Pleistocene (MIS 3) clay-rich deposit of La Chauverie (Charente, SW France) have been characterized for mineral composition. The lower part of this 75 cm-thick karst deposit preserves a mammal fauna typical of temperate climate, followed by an assemblage pointing to a colder phase. The clay fraction of both horizons mostly results from mineral transformations of the clays contained in the sediments of the Paleogene formation surrounding the cave. Because clay mineral properties and changes intimately depend on the physico-chemical conditions and reaction kinetics prevailing at a given time in the soils, they are highly temperature-related. Notably, changes are rapid under temperate conditions, but slow in tundra-like cold contexts. As shown by the altered inherited mica-illite, as well as by the increase of crystallinity of kaolinite particles, at La Chauverie these transformations were marked in the stratigraphically lower part of the deposit formed under temperate conditions. Conversely, as reflected by the reduction of the kaolinite/smectite ratio characterizing the sediments of the upper horizon, the pedological evolution was limited during the subsequent cold phase. Here, both illite/smectite and kaolinite/smectite mixed layers become smectite-richer than their equivalent in the Paleogene. The parallelism between paleontological evidence and mineral signature in recording a relatively rapid (millennial-scale) shift towards colder conditions suggests that clay mineral assemblages from cave deposits can be used to assess paleoclimatic and paleoenvironmental dynamics at local scale. Nonetheless, future research should test this potential tool in more appropriate, thicker deposits investigated using other independent paleobiological and geochemical indicators. © 2010 Elsevier Ltd and INQUA. Source

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