Skip to Main content Skip to Navigation
Journal articles

A Cenozoic-style scenario for the end-Ordovician glaciation

Abstract : The end-Ordovician was an enigmatic interval in the Phanerozoic, known for massive glaciation potentially at elevated CO 2 levels, biogeochemical cycle disruptions recorded as large isotope anomalies and a devastating extinction event. Ice-sheet volumes claimed to be twice those of the Last Glacial Maximum paradoxically coincided with oceans as warm as today. Here we argue that some of these remarkable claims arise from undersampling of incomplete geological sections that led to apparent temporal correlations within the relatively coarse resolution capability of Palaeozoic biochronostratigraphy. We examine exceptionally complete sedimentary records from two, low and high, palaeolatitude settings. Their correlation framework reveals a Cenozoic-style scenario including three main glacial cycles and higher-order phenomena. This necessitates revision of mechanisms for the end-Ordovician events, as the first extinction is tied to an early phase of melting, not to initial cooling, and the largest d 13 C excursion occurs during final deglaciation, not at the glacial apex.
Document type :
Journal articles
Complete list of metadata

Cited literature [60 references]  Display  Hide  Download
Contributor : Isabelle Dubigeon Connect in order to contact the contributor
Submitted on : Thursday, January 29, 2015 - 10:43:39 AM
Last modification on : Tuesday, October 19, 2021 - 10:52:54 PM
Long-term archiving on: : Saturday, April 15, 2017 - 10:27:39 PM


Publisher files allowed on an open archive




Jean-François Ghienne, André Desrochers, T.R.A. Vandenbroucke, Aïcha Achab, Esther Asselin, et al.. A Cenozoic-style scenario for the end-Ordovician glaciation. Nature Communications, Nature Publishing Group, 2014, 5, n°4485. ⟨10.1038/ncomms5485⟩. ⟨insu-01061400⟩



Record views


Files downloads