Articles | Volume 21, issue 2
https://doi.org/10.5194/bg-21-437-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-21-437-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
25 Jan 2024
Research article |
| 25 Jan 2024
| 25 Jan 2024
Stable oxygen isotopes of crocodilian tooth enamel allow tracking Plio-Pleistocene evolution of freshwater environments and climate in the Shungura Formation (Turkana Depression, Ethiopia)
Axelle Gardin
CORRESPONDING AUTHOR
Laboratoire Paléontologie Evolution Paléoécosystèmes Paléoprimatologie, UMR 7262 CNRS, Université de Poitiers, Poitiers, France
Emmanuelle Pucéat
Biogéosciences, UMR 5561 CNRS, Université de Bourgogne, Dijon, France
Géraldine Garcia
Laboratoire Paléontologie Evolution Paléoécosystèmes Paléoprimatologie, UMR 7262 CNRS, Université de Poitiers, Poitiers, France
Jean-Renaud Boisserie
Laboratoire Paléontologie Evolution Paléoécosystèmes Paléoprimatologie, UMR 7262 CNRS, Université de Poitiers, Poitiers, France
Centre Français des Études Éthiopiennes, USR 3137 CNRS & Ministère des Affaires Etrangères, Addis Ababa, Ethiopia
Adélaïde Euriat
Laboratoire Paléontologie Evolution Paléoécosystèmes Paléoprimatologie, UMR 7262 CNRS, Université de Poitiers, Poitiers, France
Michael M. Joachimski
GeoZentrum Nordbayern, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
Alexis Nutz
CEREGE, Aix-Marseille Université, CNRS, IRD, Collège de France, INRAE, Aix-en-Provence, France
Mathieu Schuster
Institut Terre & Environnement de Strasbourg, UMR 7063 CNRS, Université de Strasbourg, Strasbourg, France
Olga Otero
Laboratoire Paléontologie Evolution Paléoécosystèmes Paléoprimatologie, UMR 7262 CNRS, Université de Poitiers, Poitiers, France
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Short summary
Short summary
This study examines how weathering in the Southern Pyrenees responded to a significant global warming event that occurred 56 million years ago. We found that changes in rainfall and erosion significantly influenced how minerals break down, and that the weathering response evolved from the continental interior to the marine environment. These results highlight regional variations in Earth's surface response to climatic perturbations and the processes at play in response to global warming.
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Short summary
We introduce a novel approach using stable oxygen isotopes from crocodilian fossil teeth to unravel palaeohydrological changes in past continental contexts. Applying it to the Plio-Pleistocene Ethiopian Shungura Formation, we found a significant increase in δ18O in the last 3 million years, likely due to monsoonal shifts and reduced rainfall, and that the local diversity of waterbodies (lakes, rivers, ponds) became restricted.
We introduce a novel approach using stable oxygen isotopes from crocodilian fossil teeth to...
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