Thomas Munier, Jean-François Deconinck, Pierre Pellenard, Stephen P. Hesselbo, James B. Riding, Clemens V. Ullmann, Cédric Bougeault, Mathilde Mercuzot, Anne-Lise Santoni, Émilia Huret, and Philippe Landrein
Clay minerals are witnesses of alteration conditions in continental environments. Lacking high-resolution data on clay minerals, this work highlights wet and semi-arid cycles at mid-latitude in the upper Sinemurian. The higher proportion of kaolinite in the upper part of the obtusum zone and in the oxynotum zone indicates an increase in hydrolysis conditions in a warmer period confirmed by carbon isotopes.
Our micropaleontological analyses on three cores from New Jersey (USA) show that the late Maastrichtian warming event (66.4–66.1 Ma), characterized by a ~ 4.0 °C warming of sea waters on the New Jersey paleoshelf, resulted in a disruption of phytoplankton communities and a stressed benthic ecosystem. This increased ecosystem stress during the latest Maastrichtian potentially primed global ecosystems for the subsequent mass extinction following the Cretaceous–Paleogene boundary impact.
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