Water discharge variations control fluvial stratigraphic architecture in the Middle Eocene Escanilla formation, Spain

Article Article scientifique Article Water discharge variations control fluvial stratigraphic architecture in the Middle Eocene Escanilla formation, Spain eng 2023-04-26 author Sharma Nikhil 0000-0002-8256-0524 Department of Earth Sciences, University of Geneva, 13 Rue des Maraîchers, 1205, Geneva, Switzerland. nikhil.sharma@unige.ch. 865469 author Whittaker Alexander C Department of Earth Science and Engineering, Imperial College London, South Kensington, London, SW7 2AZ, UK. author Watkins Stephen Department of Earth Sciences, University of Geneva, 13 Rue des Maraîchers, 1205, Geneva, Switzerland. 919333 author Valero Montesa Luis Department of Earth Sciences, University of Geneva, 13 Rue des Maraîchers, 1205, Geneva, Switzerland.,Paleomagnetic Laboratory CCiTUB-Geo3Bcn, Geosciences Barcelona-CSIC, C/Lluis Solé I Sabarís S/N, 08028, Barcelona, Spain. 919271 author Vérité Jean LPG - Le Mans, UFR Sciences Et Techniques, Université du Maine, 72089, Le Mans Cedex 9, France. author Puigdefabregas Cai Department of Earth and Ocean Dynamics, Faculty of Earth Sciences, Universitat de Barcelona, C/ Martí I Franquès, S/N, 08028, Barcelona, Spain. author Adatte Thierry Institute of Earth Sciences (ISTE), University of Lausanne, Bâtiment Géopolis, 1015, Lausanne, Switzerland. author Garcés Miguel Department of Earth and Ocean Dynamics, Faculty of Earth Sciences, Universitat de Barcelona, C/ Martí I Franquès, S/N, 08028, Barcelona, Spain.,UB-Geomodels Research Institute, Universitat de Barcelona, 08028, Barcelona, Spain. author Guillocheau François Géosciences Rennes, Université de Rennes 1, Campus de Beaulieu, 35042, Rennes Cedex, France. author Castelltort Sébastien 0000-0002-6405-4038 Department of Earth Sciences, University of Geneva, 13 Rue des Maraîchers, 1205, Geneva, Switzerland. 761351 Rectorat et adjoints (REC) 6834 10.1038/s41598-023-33600-6 37100796 2045-2322 PMC10133228 https://www.nature.com/articles/s41598-023-33600-6 Ancient fluvial deposits typically display repetitive changes in their depositional architecture such as alternating intervals of coarse-grained highly amalgamated (HA), laterally-stacked, channel bodies, and finer-grained less amalgamated (LA), vertically-stacked, channels encased in floodplain deposits. Such patterns are usually ascribed to slower, respectively higher, rates of base level rise (accommodation). However, "upstream" factors such as water discharge and sediment flux also play a potential role in determining stratigraphic architecture, yet this possibility has never been tested despite the recent advances in the field of palaeohydraulic reconstructions from fluvial accumulations. Here, we chronicle riverbed gradient evolution within three Middle Eocene (~ 40 Ma) fluvial HA-LA sequences in the Escanilla Formation in the south-Pyrenean foreland basin. This work documents, for the first time in a fossil fluvial system, how the ancient riverbed systematically evolved from lower slopes in coarser-grained HA intervals, and higher slopes in finer-grained LA intervals, suggesting that bed slope changes were determined primarily by climate-controlled water discharge variations rather than base level changes as often hypothesized. This highlights the important connection between climate and landscape evolution and has fundamental implications for our ability to reconstruct ancient hydroclimates from the interpretation of fluvial sedimentary sequences. Dewey 550 Swiss National Science Foundation Earth Surface Signaling Systems: Upstream versus downstream propagation of climatic signals from source-to-sink, in nature and experiments 182017 CH 42 Département des sciences de la Terre 154 false 672 Earth Surface Dynamics Scientific reports 13 1 e47b92af-fe4d-46a8-be12-01211b3f986d Article (Published version) Public Article_scientifique_from_crossref.pdf 5996875 application/pdf CC BY-4.0 5c4431460f367ad534a597b6248ef4e2f7a876b9396943dc30152a8433ec0676 openAccess Faculté des sciences / Section des sciences de la Terre et de l'Environnement / Département des sciences de la Terre

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Water discharge variations control fluvial stratigraphic architecture in the Middle Eocene Escanilla formation, Spain	Scientific reports			2023	5	6

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