Models of the Cretaceous–Tertiary impact at Chicxulub have suggested that the thermal radiation released by the impact would have been sufficient to ignite extensive wildfires. Eight non-marine K–T sequences stretching across North America have been studied in order to test this hypothesis. Multiple ...

The monophyletic Palaeozoic chelicerate order Eurypterida, contains around 65 genera and is the subject of the first large-scale phylogenetic analysis of the group (201 morphological characters for the entire Chelicerata). Many eurypterids are known from fragmentary remains, and the 40 best-known ...

A unique and spectacular Early Palaeozoic tropical archipelago is being unearthed near Churchill, Manitoba, Canada. Islands composed of Proterozoic quartzite are surrounded by shallow marine deposits of Late Ordovician and Early Silurian age. Field research since 1996 has revealed a total of 16 ...

In 1874, Charles Barrois reported a pterodactyl tibia, from the White Chalk (“Craie blanche”) which was then exploited in underground quarries at Lezennes (now in the suburbs of Lille). He referred it to Pterodactylus giganteus, a species from the English Chalk. Although no detailed description ...

Qu’entend t-on par territoire forestier ? Doit-on le réduire à l’influence et au travail des aménageurs et techniciens en liaison avec une approche marchande qui s’est développée surtout depuis le XXe siècle ? L’essor des activités récréatives, des politiques de protection, du maintien de certaines ...

Animals fractionate nitrogen and organic carbon isotopes during food digestion and preferentially excrete the lighter isotopes. New body tissues subsequently grown become about +3.4‰ more positive in d15N than their food and about +1‰ more enriched in d13C. This simple relationship between consumer ...

Exemple de l’invasion par une essence exotique, le cerisier tardif. Qu’entend t-on par territoire forestier ? Doit-on le réduire à l’influence et au travail des aménageurs et techniciens en liaison avec une approche marchande qui s’est développée surtout depuis le XXe siècle ? L’essor des activités ...

Clay-rich and siliceous sedimentary rocks of lowermost Cambrian age on the Yangtze Platform, China contain a large amount of siliceous microfossils. Based on their high content of siliceous hard parts, these rocks are in fact biosiliceous sediments. In more clay-rich lithologies, diagenetic dissolution ...