Search

Your search keyword '"Eynaud, Frédérique"' showing total 279 results
Start Over Author "Eynaud, Frédérique"
279 results on '"Eynaud, Frédérique"'

5. Modern relationships between microscopic charcoal in marine sediments and fire regimes on adjacent landmasses to refine the interpretation of marine paleofire records: An Iberian case study

Author

Genet, Marion, Daniau, Anne-Laure, Mouillot, Florent, Hanquiez, Vincent, Schmidt, Sabine, David, Valérie, Georget, Muriel, Abrantes, Fatima, Anschutz, Pierre, Bassinot, Franck, Bonnin, Jérome, Dennielou, Bernard, Eynaud, Frédérique, Hodell, David A., Mulder, Thierry, Naughton, Filipa, Rossignol, Linda, Tzedakis, Polychronis, and Sánchez-Goñi, Maria Fernanda

Published
2021
Full Text
View/download PDF

7. Stratigraphy in the Greenland/Iceland/Norwegian (GIN) seas: A multiproxy approach on Pleistocene sediments

Author

Sabine-Lamoureux, Marjolaine E.J., primary, Eynaud, Frédérique, additional, Zaragosi, Sébastien, additional, Giraudeau, Jacques, additional, Debret, Maxime, additional, Rossignol-Malaize, Linda, additional, Charlier, Karine, additional, Billy, Isabelle, additional, Malaize, Bruno, additional, Daynac, Jimmy, additional, Marches, Elodie, additional, and Garlan, Thierry, additional

Published
2022
Full Text
View/download PDF

8. Distribution of common modern dinoflagellate cyst taxa in surface sediments of the Northern Hemisphere in relation to environmental parameters: The new n=1968 database

Author

de Vernal, Anne, Radi, Taoufik, Zaragosi, Sebastien, Van Nieuwenhove, Nicolas, Rochon, André, Allan, Estelle, De Schepper, Stijn, Eynaud, Frédérique, Head, Martin J., Limoges, Audrey, Londeix, Laurent, Marret, Fabienne, Matthiessen, Jens, Penaud, Aurélie, Pospelova, Vera, Price, Andrea, and Richerol, Thomas

Published
2020
Full Text
View/download PDF

10. Atlantic circulation changes across a stadial-interstadial transition

Author

Research Council of Norway, Agencia Estatal de Investigación (España), Waelbroeck, Claire [0000-0002-7256-5727], Tjiputra, Jerry [0000-0002-4600-2453], Guo, Chuncheng [0000-0001-6276-6499], Nisancioglu, Kerim H. [0000-0002-5737-5765], Eynaud, Frédérique [0000-0003-1283-7425], Martín Lebreiro, Susana [0000-0003-1478-2448], Nave, Silvia [0000-0003-0845-1044], Waelbroeck, Claire, Tjiputra, Jerry, Guo, Chuncheng, Nisancioglu, Kerim H., Jansen, Eystein, Vázquez Riveiros, Natalia, Toucanne, Samuel, Eynaud, Frédérique, Rossignol, L., Dewilde, Fabien, Marchès, Elodie, Martín Lebreiro, Susana, Nave, Silvia, Research Council of Norway, Agencia Estatal de Investigación (España), Waelbroeck, Claire [0000-0002-7256-5727], Tjiputra, Jerry [0000-0002-4600-2453], Guo, Chuncheng [0000-0001-6276-6499], Nisancioglu, Kerim H. [0000-0002-5737-5765], Eynaud, Frédérique [0000-0003-1283-7425], Martín Lebreiro, Susana [0000-0003-1478-2448], Nave, Silvia [0000-0003-0845-1044], Waelbroeck, Claire, Tjiputra, Jerry, Guo, Chuncheng, Nisancioglu, Kerim H., Jansen, Eystein, Vázquez Riveiros, Natalia, Toucanne, Samuel, Eynaud, Frédérique, Rossignol, L., Dewilde, Fabien, Marchès, Elodie, Martín Lebreiro, Susana, and Nave, Silvia

Abstract

[EN] We combine consistently dated benthic carbon isotopic records distributed over the entire Atlantic Ocean with numerical simulations performed by a glacial configuration of the Norwegian Earth System Model with active ocean biogeochemistry in order to interpret the observed Cibicides 13C changes at the stadial-interstadial transition corresponding to the end of Heinrich Stadial 4 (HS4) in terms of ocean circulation and remineralization changes. We show that the marked increase in Cibicides 13C observed at the end of HS4 between g1/42000 and 4200gm in the Atlantic can be explained by changes in nutrient concentrations as simulated by the model in response to the halting of freshwater input in the high-latitude glacial North Atlantic. Our model results show that this Cibicides 13C signal is associated with changes in the ratio of southern-sourced (SSW) versus northern-sourced (NSW) water masses at the core sites, whereby SSW is replaced by NSW as a consequence of the resumption of deep-water formation in the northern North Atlantic and Nordic Seas after the freshwater input is halted. Our results further suggest that the contribution of ocean circulation changes to this signal increases from g1/440g% at 2000gm to g1/480g% at 4000gm. Below g1/44200gm, the model shows little ocean circulation change but an increase in remineralization across the transition marking the end of HS4. The simulated lower remineralization during stadials compared to during interstadials is particularly pronounced in deep subantarctic sites, in agreement with the decrease in the export production of carbon to the deep Southern Ocean during stadials found in previous studies.

Published
2023

19. A two-million-year-long hydroclimatic context for hominin evolution in southeastern Africa

Author

Caley, Thibaut, Extier, Thomas, Collins, James A., Schefuß, Enno, Dupont, Lydie, Malaizé, Bruno, Rossignol, Linda, Souron, Antoine, McClymont, Erin L., Jimenez-Espejo, Francisco J., García-Comas, Carmen, Eynaud, Frédérique, Martinez, Philippe, Roche, Didier M., Jorry, Stephan J., Charlier, Karine, Wary, Mélanie, Gourves, Pierre-Yves, Billy, Isabelle, and Giraudeau, Jacques

Published
2018
Full Text
View/download PDF

20. Atlantic circulation changes across a stadial–interstadial transition

Author

Waelbroeck, Claire, primary, Tjiputra, Jerry, additional, Guo, Chuncheng, additional, Nisancioglu, Kerim H., additional, Jansen, Eystein, additional, Vázquez Riveiros, Natalia, additional, Toucanne, Samuel, additional, Eynaud, Frédérique, additional, Rossignol, Linda, additional, Dewilde, Fabien, additional, Marchès, Elodie, additional, Lebreiro, Susana, additional, and Nave, Silvia, additional

Published
2023
Full Text
View/download PDF

21. Human settlement and landscape dynamics on the coastline south of the Gironde estuary (SW France): A multi-proxy approach

Author

Agence Nationale de la Recherche (France), Région Nouvelle-Aquitaine, López-Romero, Elías, Verdin, Florence, Eynaud, Frédérique, Culioli, Camile, Hoffmann, Alizé, Huchet, Jean-Bernard, Rollin, Jérémy, Stéphan, Pierre, Agence Nationale de la Recherche (France), Région Nouvelle-Aquitaine, López-Romero, Elías, Verdin, Florence, Eynaud, Frédérique, Culioli, Camile, Hoffmann, Alizé, Huchet, Jean-Bernard, Rollin, Jérémy, and Stéphan, Pierre

Abstract

The Gironde estuary in SW France is the largest in Western Europe and has attracted human populations since prehistoric times. From the 1970s to the 1990s, intense archaeological research was undertaken on the long and highly dynamic coastline just south of the estuary mouth. In recent years, the combined action of increased coastal erosion and human pressure has proved a serious threat to the integrity of archaeological sites in the area. As a consequence, a whole array of previously unrecorded archaeological remains across the intertidal zone and coastal strip is being exposed. In this context, innovative interdisciplinary research since 2014 is yielding new information about the settlement and landscape dynamics and about the long-term interaction between human societies and the environment. The sedimentary context and the exceptional preservation conditions of organic remains have made possible a multi-proxy approach combining archaeological, geomorphological, palaeobiological, and archaeoentomological methods. In this paper we discuss the different approaches and the way they jointly contribute to the project. The results obtained so far from this multi-proxy approach challenge the traditional view of the historic occupation and the landscape dynamics around the Gironde estuary from prehistoric times to antiquity. They show that the intense occupation of this area during certain periods of human history is related to the development of marshy environments, which can now be analyzed at higher temporal resolution owing to this approach.

Published
2023

24. Consistently dated Atlantic sediment cores over the last 40 thousand years

Author

Waelbroeck, Claire, Lougheed, Bryan C., Vazquez Riveiros, Natalia, Missiaen, Lise, Pedro, Joel, Dokken, Trond, Hajdas, Irka, Wacker, Lukas, Abbott, Peter, Dumoulin, Jean-Pascal, Thil, François, Eynaud, Frédérique, Rossignol, Linda, Fersi, Wiem, Albuquerque, Ana Luiza, Arz, Helge, Austin, William E. N., Came, Rosemarie, Carlson, Anders E., Collins, James A., Dennielou, Bernard, Desprat, Stéphanie, Dickson, Alex, Elliot, Mary, Farmer, Christa, Giraudeau, Jacques, Gottschalk, Julia, Henderiks, Jorijntje, Hughen, Konrad, Jung, Simon, Knutz, Paul, Lebreiro, Susana, Lund, David C., Lynch-Stieglitz, Jean, Malaizé, Bruno, Marchitto, Thomas, Martínez-Méndez, Gema, Mollenhauer, Gesine, Naughton, Filipa, Nave, Silvia, Nürnberg, Dirk, Oppo, Delia, Peck, Victoria, Peeters, Frank J. C., Penaud, Aurélie, Portilho-Ramos, Rodrigo da Costa, Repschläger, Janne, Roberts, Jenny, Rühlemann, Carsten, Salgueiro, Emilia, Sanchez Goni, Maria Fernanda, Schönfeld, Joachim, Scussolini, Paolo, Skinner, Luke C., Skonieczny, Charlotte, Thornalley, David, Toucanne, Samuel, Rooij, David Van, Vidal, Laurence, Voelker, Antje H. L., Wary, Mélanie, Weldeab, Syee, and Ziegler, Martin

Published
2019
Full Text
View/download PDF

26. Supplementary material to "Atlantic circulation changes across a stadial-interstadial transition"

Author

Waelbroeck, Claire, primary, Tjiputra, Jerry, additional, Guo, Chuncheng, additional, Nisancioglu, Kerim H., additional, Jansen, Eystein, additional, Vazquez Riveiros, Natalia, additional, Toucanne, Samuel, additional, Eynaud, Frédérique, additional, Rossignol, Linda, additional, Dewilde, Fabien, additional, Marchès, Elodie, additional, Lebreiro, Susana, additional, and Nave, Silvia, additional

Published
2022
Full Text
View/download PDF

27. Atlantic circulation changes across a stadial-interstadial transition

Author

Waelbroeck, Claire, primary, Tjiputra, Jerry, additional, Guo, Chuncheng, additional, Nisancioglu, Kerim H., additional, Jansen, Eystein, additional, Vazquez Riveiros, Natalia, additional, Toucanne, Samuel, additional, Eynaud, Frédérique, additional, Rossignol, Linda, additional, Dewilde, Fabien, additional, Marchès, Elodie, additional, Lebreiro, Susana, additional, and Nave, Silvia, additional

Published
2022
Full Text
View/download PDF

29. Holocene climate dynamics on the European scale: Insights from a coastal archaeological record from the temperate Bay of Biscay (SW France)

Author

Agence Nationale de la Recherche (France), Conseil régional d'Aquitaine, Eynaud, Frédérique, Verdin, Florence, Mary, Yannick, Beaudouin, Célia, López-Romero, Elías, Penaud, Aurélie, Colin, Christophe, Culioli, Camile, Agence Nationale de la Recherche (France), Conseil régional d'Aquitaine, Eynaud, Frédérique, Verdin, Florence, Mary, Yannick, Beaudouin, Célia, López-Romero, Elías, Penaud, Aurélie, Colin, Christophe, and Culioli, Camile

Abstract

The main drivers of Europe's climate during the Holocene result from the coupling and interplay of external and internal radiative processes with the shifting patterns of many dynamic components (e.g. glaciers, ocean currents, wind fields, vegetation cover). Those driving forces were expressed across a range of geographical scales, from local to global, in a diverse set of records forming a patchwork of evidence as to the fundamental pacing effect of climate on past ecosystems. Various sedimentary deposits resulting from those complex forcing contexts bear climatic signatures that it is not always easy to disentangle especially with respect to local factors. The present paper focuses on a coastal archaeological site on the Medoc peninsula (the Lède du Gurp site in south-western France) that records Holocene palaeoenvironmental changes, decoded here century after century and integrated with ongoing events on a pan-North-Atlantic scale. Based on updated geoarchaeological approaches, thanks to new applications of proxies, especially X-ray fluorescence (XRF) core scanning methods for this article, continuous sedimentary records have been analysed in order to reconstruct a regional framework for past ecosystem events, including events potentially related to human activity. Our work identifies signals on various scales in the record under study, with both long- and short-term trends and local and global imprints, but all closely bound up with proximal North Atlantic Ocean dynamics. It highlights how western European environments (and so populations) were dependent upon the linearity of climate evolution at the key Northgrippian/Meghalayan transition.

Published
2022

30. The impact of African aridity on the isotopic signature of Atlantic deep waters across the Middle Pleistocene Transition

Author

Malaizé, Bruno, Jullien, Elsa, Tisserand, Amandine, Skonieczny, Charlotte, Grousset, E. Francis, Eynaud, Frédérique, Kissel, Catherine, Bonnin, Jérôme, Karstens, Svenja, Martinez, Philippe, Bory, Aloys, Bout-Roumazeilles, Vivianne, Caley, Thibaut, Crosta, Xavier, Charlier, Karine, Rossignol, Linda, Flores, José-Abel, and Schneider, Ralph

Published
2012
Full Text
View/download PDF

33. Human settlement and landscape dynamics on the coastline south of the Gironde estuary (SW France): A multi-proxy approach.

Author

López-Romero, Elías, Verdin, Florence, Eynaud, Frédérique, Culioli, Camille, Hoffmann, Alizé, Huchet, Jean-Bernard, Rollin, Jérémy, and Stéphan, Pierre

Subjects
HUMAN settlements, ESTUARIES, LANDSCAPES, PREHISTORIC antiquities, INTERTIDAL zonation, COASTAL changes, ARCHAEOLOGICAL geology, COASTS
Abstract

The Gironde estuary in SW France is the largest in Western Europe and has attracted human populations since prehistoric times. From the 1970s to the 1990s, intense archaeological research was undertaken on the long and highly dynamic coastline just south of the estuary mouth. In recent years, the combined action of increased coastal erosion and human pressure has proved a serious threat to the integrity of archaeological sites in the area. As a consequence, a whole array of previously unrecorded archaeological remains across the intertidal zone and coastal strip is being exposed. In this context, innovative interdisciplinary research since 2014 is yielding new information about the settlement and landscape dynamics and about the long-term interaction between human societies and the environment. The sedimentary context and the exceptional preservation conditions of organic remains have made possible a multi-proxy approach combining archaeological, geomorphological, palaeobiological, and archaeoentomological methods. In this paper we discuss the different approaches and the way they jointly contribute to the project. The results obtained so far from this multi-proxy approach challenge the traditional view of the historic occupation and the landscape dynamics around the Gironde estuary from prehistoric times to antiquity. They show that the intense occupation of this area during certain periods of human history is related to the development of marshy environments, which can now be analyzed at higher temporal resolution owing to this approach. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

35. Atlantic circulation changes across a stadial-interstadial transition.

Author

Waelbroeck, Claire, Tjiputra, Jerry, Chuncheng Guo, Nisancioglu, Kerim H., Jansen, Eystein, Riveiros, Natalia Vazquez, Toucanne, Samuel, Eynaud, Frédérique, Rossignol, Linda, Dewilde, Fabien, Marchès, Elodie, Lebreiro, Susana, and Nave, Silvia

Abstract

We combine consistently dated benthic carbon isotopic records distributed over the entire Atlantic Ocean with numerical simulations performed by a glacial configuration of the Norwegian Earth System Model with active ocean biogeochemistry, in order to interpret the observed Cibicides δ13C changes at the stadial-interstadial transition corresponding to the end of Heinrich Stadial 4 (HS4) in terms of ocean circulation and remineralization changes. We show that the marked increase in Cibicides δ13C observed at the end of HS4 between ~2000 and 4200 m in the Atlantic can be explained by changes in nutrient concentrations as simulated by the model in response to the halting of freshwater input in the high latitude glacial North Atlantic. Our model results show that this Cibicides δ13C signal is associated with changes in the ratio of southern-sourced (SSW) versus northern-sourced (NSW) water masses at the core sites, whereby SSW is replaced by NSW as a consequence of the resumption of deep water formation in the northern North Atlantic and Nordic Seas after the freshwater input is halted. Our results further suggest that the contribution of ocean circulation changes to this signal increases from ~40 % at 2000 m to ~80 % at 4000 m. Below ~4200 m, the model shows little ocean circulation change but an increase in remineralization across the transition marking the end of HS4. The simulated lower remineralization during stadials than interstadials is particularly pronounced in deep subantarctic sites, in agreement with the decrease in the export production of carbon to the deep Southern Ocean during stadials found in previous studies. [ABSTRACT FROM AUTHOR]

Published
2022
Full Text
View/download PDF

36. Ocean productivity in the Gulf of Cadiz over the last 50 kyr

Author

Penaud, Aurélie, primary, Eynaud, Frédérique, additional, Etourneau, Johan, additional, Bonnin, Jérôme, additional, deVernal, Anne, additional, Zaragosi, Sébastien, additional, Kim, Jung Hyun, additional, Kang, Sujin, additional, Gal, Jong-Ku, additional, Oliveiraa, Dulce, additional, and Waelbroeck, Claire, additional

Published
2021
Full Text
View/download PDF

37. Are Past Sea-Ice Reconstructions Based on Planktonic Foraminifera Realistic? Study of the Last 50 ka as a Test to Validate Reconstructed Paleohydrography Derived from Transfer Functions Applied to Their Fossil Assemblages

Author

Eynaud, Frédérique, Zaragosi, Sébastien, Wary, Mélanie, Woussen, Emilie, Rossignol, Linda, Voisin, Adrien, Eynaud, Frédérique, Zaragosi, Sébastien, Wary, Mélanie, Woussen, Emilie, Rossignol, Linda, and Voisin, Adrien

Abstract

Since its existence, paleoceanography has relied on fossilized populations of planktonic foraminifera. Except for some extreme environments, this calcareous protist group composes most of the silty-to-sandy fraction of the marine sediments, i.e., the foraminiferal oozes, and its extraction is probably the simplest among the currently existing set of marine fossil proxies. This tool has provided significant insights in the building of knowledge on past climates based on marine archives, especially with the quantification of past hydrographical variables, which have been a turning point for major comprehensive studies and a step towards the essential junction of modelling and paleodata . In this article, using the modern analog technique and a database compiling modern analogs (n = 1007), we test the reliability of this proxy in reconstructing paleohydrographical data other than the classical sea-surface temperatures, taking advantage of an update regarding a set of extractions from the World Ocean Atlas for transfer functions. Our study focuses on the last glacial period and its high climatic variability, using a set of cores distributed along the European margin, from temperate to subpolar sites. We discuss the significance of the reconstructed parameters regarding abrupt and extreme climate events, such as the well-known Heinrich events. We tested the robustness of the newly obtained paleodata by comparing them with older published reconstructions, especially those based on the complementary dinoflagellate cyst proxy. This study shows that the potential of planktonic foraminifera permits going further in reconstructions, with a good degree of confidence; however, this implies considering ecological forcings in a more holistic perspective, with the corollary to integrate the message of this fossil protist group, i.e., the obtained parameters, in light of a cohort of other data. This article constitutes a first step in this direction.

Published
2021
Full Text
View/download PDF

38. Lateglacial and Holocene sedimentary dynamics in northwestern Baffin Bay as recorded in sediment cores from Cape Norton Shaw Inlet (Nunavut, Canada).

Author

Stevenard, Nathan, Montero‐Serrano, Jean‐Carlos, Eynaud, Frédérique, St‐Onge, Guillaume, Zaragosi, Sébastien, and Copland, Luke

Subjects
HOLOCENE Epoch, SEDIMENTS, SEA ice, ATMOSPHERIC temperature, INLETS, GLACIERS, GLACIAL landforms
Abstract

The physical, sedimentological, mineralogical and elemental geochemical properties of sediment cores AMD1803‐02BC and 01PC from the Cape Norton Shaw Inlet were investigated to reconstruct glacial sediment discharges from southeastern Manson Icefield and document the impact of ice–ocean interactions on the sediment dynamics and opening of the North Water Polynya (NOW) in northwestern Baffin Bay since the last deglaciation. Laminated glaciomarine sediments rich in quartz and feldspar are observed prior to 11 cal. ka BP and were probably deposited by hyperpycnal currents triggered by the local retreat of the southern margin of the Innuitian Ice. Detrital proxies suggest that Early Holocene sediment dynamics were mainly influenced by sea ice and iceberg rafting and meltwater discharges related to the deglaciation of eastern Smith (~11 to 10.65 cal. ka BP) and Jones (~10.7 cal. ka BP) sounds. This also provides an upper limit to the timing of formation of the NOW. The high detrital carbonate contents during 8.8 to 6.6 cal. ka BP confirm that enhanced carbonate‐rich sediment export from Nares Strait to northern Baffin Bay occurred during and after the deglaciation of Kennedy Channel (8.8 to 8.2 cal. ka BP). Canadian Shield sediment inputs have dominated since 6.6 cal. ka BP, indicating that sedimentation is mainly influenced by Cape Norton Shaw glacier discharges. The lower level of sedimentation recorded in core 01PC during the Middle to Late Holocene suggests an accelerated landward retreat of the Cape Norton Shaw glaciers in response to warmer marine conditions. During the Neoglacial period, higher sedimentation rates and detrital proxies in the cores suggest increased glacial erosional processes, probably associated with the long‐term declines in boreal summer insolation and glacier growth. Finally, mineralogical and grain‐size data in core 02BC support the idea that increased Arctic atmospheric temperatures have had an important influence on the glacial dynamics during the industrial period. [ABSTRACT FROM AUTHOR]

Published
2022
Full Text
View/download PDF

41. Monsoonal Forcing of European Ice‐Sheet Dynamics During the Late Quaternary

Author

Kaboth-Bahr, Stefanie, Bahr, André, Zeeden, Christian, Toucanne, Samuel, Eynaud, Frédérique, Jiménez-Espejo, Francisco, Röhl, Ursula, Friedrich, Oliver, Pross, Jörg, Löwemark, Ludvig, Lourens, Lucas J., Stratigraphy & paleontology, Stratigraphy and paleontology, Stratigraphy & paleontology, Stratigraphy and paleontology, Heidelberg University, Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Géodynamique et enregistrement Sédimentaire - Geosciences Marines (GM-LGS), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), National Oceanography Centre [Southampton] (NOC), University of Southampton, Federal Institute of Hydrology (BfG), Utrecht University [Utrecht], Laboratoire Géodynamique et enregistrement Sédimentaire (LGS), Géosciences Marines (GM), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE)

Subjects
Ice-sheet dynamics, European Ice Sheet dynamics, 010504 meteorology & atmospheric sciences, low‐latitude forcing of high‐latitude glaciations, Earth and Planetary Sciences(all), 010502 geochemistry & geophysics, Monsoon, 01 natural sciences, Mediterranean Outflow variability, Continental margin, marine‐terrestrial feedback in the Euro‐Mediterranean realm, Glacial period, Meltwater, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, [PHYS]Physics [physics], low-latitude forcing of high-latitude glaciations, geography, geography.geographical_feature_category, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Lead (sea ice), glacial climate variability, Geophysics, Oceanography, marine-terrestrial feedback in the Euro-Mediterranean realm, 13. Climate action, General Earth and Planetary Sciences, Ice sheet, Quaternary, Geology
Abstract

The dynamics of Northern Hemisphere ice sheets during Late Quaternary glacials have yet been dominantly examined from a Laurentide Ice Sheet perspective, which helped shaping the idea of moisture-starved glacials and small-scale ice volume variability. However, the waxing and waning of the European Ice Sheet (EIS) casts doubt on this perception. Understanding EIS dynamics under glacial boundary conditions is crucial because its meltwater pulses influence global climate by weakening deepwater formation in the North Atlantic Ocean. Here we show that the advection of subtropical water toward the continental margin of western Europe lead to enhanced moisture availability on the continent and fueled the growth of EIS lobes during glacials. This warm-water pooling was caused by monsoonally paced enhanced Mediterranean Outflow Water (MOW) entrainment that dragged subtropical surface waters toward the European margin. This mechanism presents a yet unrecognized marine-terrestrial pathway that allows low-latitude forcing to shape high-latitude glaciations. Plain Language Summary The build-up of glacial ice shields required large amounts of atmospheric precipitating as snow. However, under full glacial conditions, cold surface oceans reduce the amount of evaporation, which counteracts the growth of large continental ice shields. Our study aims to unravel the source and transport pathways of moisture that helped to rapidly form the European Ice Shield during the past two glacials. We propose the novel concept that the outflow of dense Mediterranean water into the North Atlantic played a decisive role as it helped to "drag" warm surface waters toward the European Margin by strengthening the Azores Current. This warm, subtropical water current supplied vast amounts of moisture, which then was transported northward into continental Europe and fueled ice sheet growth. The strength of Mediterranean Outflow Water discharge into the Atlantic strongly depends on monsoonal activity in its source region in the Eastern Mediterranean Sea. Thus, warm water advection toward western Europe and associated glacier growth of the European Ice Shield are intimately linked to low-latitude climate changes, closely following the similar to 21 kyr beat of orbital precession.

Published
2018

43. The Cenozoic palaeoenvironment of the Arctic Ocean

Author

Moran, Kathryn, Backman, Jan, Brinkhuis, Henk, Clemens, Steven C., Cronin, Thomas, Dickens, Gerald R., and Eynaud, Frédérique

Subjects
Arctic Ocean -- Natural history -- Environmental aspects, Climatic changes -- History -- Environmental aspects, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

The history of the Arctic Ocean during the Cenozoic era (0-65 million years ago) is largely unknown from direct evidence. Here we present a Cenozoic palaeoceanographic record constructed from >400 m of sediment core from a recent drilling expedition to the Lomonosov ridge in the Arctic Ocean. Our record shows a palaeoenvironmental transition from a warm 'greenhouse' world, during the late Palaeocene and early Eocene epochs, to a colder 'icehouse' world influenced by sea ice and icebergs from the middle Eocene epoch to the present. For the most recent ~14 Myr, we find sedimentation rates of 1-2 cm per thousand years, in stark contrast to the substantially lower rates proposed in earlier studies; this record of the Neogene reveals cooling of the Arctic that was synchronous with the expansion of Greenland ice (~3.2 Myr ago) and East Antarctic ice (~14 Myr ago). We find evidence for the first occurrence of ice-rafted debris in the middle Eocene epoch (~45 Myr ago), some 35 Myr earlier than previously thought; fresh surface waters were present at ~49 Myr ago, before the onset of ice-rafted debris. Also, the temperatures of surface waters during the Palaeocene/Eocene thermal maximum (~55 Myr ago) appear to have been substantially warmer than previously estimated. The revised timing of the earliest Arctic cooling events coincides with those from Antarctica, supporting arguments for bipolar symmetry in climate change. The Cenozoic Arctic Ocean Little was known about the environmental history of the Arctic Ocean before the 2004 ACEX ocean drilling expedition. Now a 430-metre sea floor sediment core has been recovered and its analysis, reported this week, provides a 56-million-year climate record spanning the transition from a warm 'greenhouse' to a colder 'icehouse' world. Several key events are identified during the Cenozoic: surface waters during the Palaeocene/Eocene thermal maximum (55 million years ago) were much warmer than previous estimates; surface-water freshening confirms an intensified hydrological cycle about 49 million years ago; and the first ice-rafted debris occurred 45 million years ago, 35 million years earlier than was thought. The revised timings for the earliest Arctic cooling events coincide with those for Antarctica, supporting suggestions that global climate changed symmetrically about the poles. Analysis of Arctic Ocean sediment core spanning more than 50 million years identifies several key features of Arctic climate history -- the revised timing of the earliest Arctic cooling events implied by this record coincides with those from Antarctica, supporting arguments that climate change is symmetric about the Earth's polar regions., Author(s): Kathryn Moran [sup.1] [sup.31] , Jan Backman [sup.2] , Henk Brinkhuis [sup.3] , Steven C. Clemens [sup.4] , Thomas Cronin [sup.5] , Gerald R. Dickens [sup.6] , Frédérique Eynaud [...]

Published
2006
Full Text
View/download PDF

46. Potentialités et contraintes d’occupation du littoral du Bas-Médoc : bilan du projet Litaq et réflexions sur les paléo-risques durant les périodes protohistoriques

Author

Verdin, Florence, Eynaud, Frédérique, Arnaud-Fassetta, Gilles, Stéphan, Pierre, Costa, Stéphane, Suanez, Serge, Bertrand, Frédéric, Ausonius-Institut de recherche sur l'Antiquité et le Moyen âge, Université Bordeaux Montaigne-Centre National de la Recherche Scientifique (CNRS), Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Pôle de recherche pour l'organisation et la diffusion de l'information géographique (PRODIG), Université Paris 1 Panthéon-Sorbonne (UP1)-Institut de Recherche pour le Développement (IRD)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris-Sorbonne (UP4)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Littoral, Environnement, Télédétection, Géomatique (LETG - Brest), Littoral, Environnement, Télédétection, Géomatique UMR 6554 (LETG), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN), Université de Nantes (UN)-Université de Nantes (UN)-Université de Caen Normandie (UNICAEN), Université de Nantes (UN)-Université de Nantes (UN), Littoral, Environnement, Télédétection, Géomatique (LETG - Caen), Pôle de recherche pour l'organisation et la diffusion de l'information géographique (PRODIG (UMR_8586 / UMR_D_215 / UM_115)), Université Paris 1 Panthéon-Sorbonne (UP1)-Institut de Recherche pour le Développement (IRD)-AgroParisTech-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), ANR-10-LABX-0052,LaScArBx,Using the world in ancient societies : processes and forms of appropriation of space in Long Time(2010), ANR-10-IDEX-0003,IDEX BORDEAUX,Initiative d'excellence de l'Université de Bordeaux(2010), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Sorbonne (UP4)-École pratique des hautes études (EPHE)-Institut de Recherche pour le Développement (IRD)-Université Panthéon-Sorbonne (UP1), Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Brest (UBO)-École pratique des hautes études (EPHE)-Université de Nantes (UN)-Université d'Angers (UA)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 2 (UR2), Normandie Université (NU)-Normandie Université (NU), Institut de Recherche pour le Développement (IRD)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Université Panthéon-Sorbonne (UP1)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), ANR: 10-LABX-0052,LaScArBx,Using the world in ancient societies : processes and forms of appropriation of space in Long Time(2010), and ANR-10-IDEX-03-02/10-LABX-0045,COTE,COntinental To coastal Ecosystems: evolution, adaptability and governance(2010)

Subjects
[SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

47. Humans and their environment on the Médoc coastline from the Mesolithic to the Roman period

Author

Verdin, Florence, Eynaud, Frédérique, Stéphan, Pierre, Arnaud-Fassetta, Gilles, Bosq, Mathieu, BERTRAND, Frédéric, Marchand, Grégor, Suanez, Serge, Coutelier, Clément, Comte, Florent, Wagner, Stefanie, Belingard, Christelle, Ard, Vincent, Manen, Claire, Saint-Sever, Guillaume, Ausonius-Institut de recherche sur l'Antiquité et le Moyen âge, Université Bordeaux Montaigne (UBM)-Centre National de la Recherche Scientifique (CNRS), Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Littoral, Environnement, Télédétection, Géomatique UMR 6554 (LETG), Université de Brest (UBO)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (Nantes Univ - IGARUN), Nantes Université - pôle Humanités, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Humanités, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ), Pôle de recherche pour l'organisation et la diffusion de l'information géographique (PRODIG), Université Paris 1 Panthéon-Sorbonne (UP1)-Institut de Recherche pour le Développement (IRD)-Université Paris-Sorbonne (UP4)-AgroParisTech-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), De la Préhistoire à l'Actuel : Culture, Environnement et Anthropologie (PACEA), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), Pôle de recherche pour l'organisation et la diffusion de l'information géographique (PRODIG (UMR_8586 / UMR_D_215 / UM_115)), Université Paris 1 Panthéon-Sorbonne (UP1)-Institut de Recherche pour le Développement (IRD)-AgroParisTech-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Centre de Recherche en Archéologie, Archéosciences, Histoire (CReAAH), Le Mans Université (UM)-Université de Rennes (UR)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Université de Nantes - UFR Histoire, Histoire de l'Art et Archéologie (UFR HHAA), Université de Nantes (UN)-Université de Nantes (UN)-Ministère de la Culture (MC), Littoral, Environnement, Télédétection, Géomatique (LETG - Brest), Université de Brest (UBO)-Université de Rennes 2 (UR2)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Nantes Université (Nantes Univ)-Littoral, Environnement, Télédétection, Géomatique UMR 6554 (LETG), Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (Nantes Univ - IGARUN), Nantes Université (Nantes Univ), Chemical Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Laboratoire de Géographie Physique et Environnementale (GEOLAB), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut Sciences de l'Homme et de la Société (IR SHS UNILIM), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Préhistoire et Technologie (PréTech), Université Paris Nanterre (UPN)-Centre National de la Recherche Scientifique (CNRS), Travaux et recherches archéologiques sur les cultures, les espaces et les sociétés (TRACES), École des hautes études en sciences sociales (EHESS)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université de Toulouse (UT)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), ANR-10-IDEX-0003,IDEX BORDEAUX,Initiative d'excellence de l'Université de Bordeaux(2010), Université Bordeaux Montaigne-Centre National de la Recherche Scientifique (CNRS), UMR 5805 Environnements et Paléoenvironnements Océaniques et Continentaux (EPOC), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN), Université de Nantes (UN)-Université de Nantes (UN)-Université de Caen Normandie (UNICAEN), Université de Nantes (UN)-Université de Nantes (UN), Université Paris 1 Panthéon-Sorbonne (UP1)-Institut de Recherche pour le Développement (IRD)-AgroParisTech-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), Biodiversité, Gènes & Communautés (BioGeCo), Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Université Clermont Auvergne (UCA)-Institut Sciences de l'Homme et de la Société (IR SHS UNILIM), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), Ministère de la Culture et de la Communication (MCC)-École des hautes études en sciences sociales (EHESS)-Université Toulouse - Jean Jaurès (UT2J)-Centre National de la Recherche Scientifique (CNRS), Nantes Université (NU)-Ministère de la Culture (MC)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Le Mans Université (UM), Cluster of Excellence COTE and LaScArBx - ANR-10-LABX-45) funded by the Agence Nationale de la Recherche under the Programme Investissement d’Avenir (reference ANR-10-IDEX-03-02)., LITAQ, ANR-10-LABX-0052,LaScArBx,Using the world in ancient societies : processes and forms of appropriation of space in Long Time(2010), Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Brest (UBO)-École pratique des hautes études (EPHE)-Université de Nantes (UN)-Université d'Angers (UA)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 2 (UR2), Normandie Université (NU)-Normandie Université (NU), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-AgroParisTech-Université Paris-Sorbonne (UP4)-École pratique des hautes études (EPHE)-Institut de Recherche pour le Développement (IRD)-Université Panthéon-Sorbonne (UP1), Centre National de la Recherche Scientifique (CNRS)-Institut Sciences de l'Homme et de la Société (IR SHS UNILIM), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Université Clermont Auvergne (UCA), École des hautes études en sciences sociales (EHESS)-Université Toulouse - Jean Jaurès (UT2J)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), Le Mans Université (UM)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Université de Nantes - UFR Histoire, Histoire de l'Art et Archéologie (UFR HHAA), ANR-10-LABX-52,LaScArBx,Labex Sciences Archéologiques de Bordeaux, ANR-10-IDEX-03-02/10-LABX-0045,COTE,COntinental To coastal Ecosystems: evolution, adaptability and governance(2010), Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), BERTRAND, Frédéric, Université de Nantes (UN)-Le Mans Université (UM)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université de Brest (UBO)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (NantesUniv – IGARUN), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut Universitaire Européen de la Mer (IUEM), and Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (NantesUniv – IGARUN)

Subjects
Bronze Age, Âge du Fer, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, Aquitaine RÉSUMÉ archéologie, Iron Age, Néolithique, érosion, Antiquité, marsh, marais, Neolithic, [SHS.ARCHEO] Humanities and Social Sciences/Archaeology and Prehistory, Holocene, Aquitaine, archaeology, [SHS.GEO]Humanities and Social Sciences/Geography, erosion, environnement, archaeology environment marsh coast erosion Holocene Neolithic Bronze Age Iron Age Antiquité Gironde Aquitaine RÉSUMÉ archéologie environnement marais littoral érosion Holocène Néolithique Âge du Bronze Âge du Fer Antiquité Gironde Aquitaine, Âge du Bronze, littoral, Gironde, [SHS.ENVIR]Humanities and Social Sciences/Environmental studies, coast, environment, Holocène
Abstract

International audience; The northern coast of the Médoc between Soulac-sur-Mer and Montalivet-les-Bains has a rich archaeological heritage that is being directly impacted by coastal erosion. A series of clay-peat palaeosols that formed in ancient estuarine marshes holds evidence of intensive occupation from the Mesolithic until the end of the Roman period. Within this framework, our research focused on the two key sites of La Lède du Gurp (Grayan-et-l'Hôpital) and L'Amélie (Soulac-sur-Mer), where an interdisciplinary approach based on comparison of archaeological, sedimentary and palaeo-environmental data has made it possible to situate the main phases of occupation in their environmental context. This work has benefited from field documentation that is exceptionally well-preserved in wet sediments sealed beneath the present-day dune system. The most fleeting traces (animal tracks) like the sturdiest anthropic structures are preserved, as are many organic remains. These items provide access to first-rate documentation for reconstructing the range of activities practised in a specific ecosystem: salt production, livestock grazing, shellfish collecting, passage and carriage, and funerary and symbolic practices. Study of occupation over the long term reveals an alternating pattern of dynamic phases and decline phases that seem to be correlated with changes in the local environment.; La côte nord médocaine, entre Soulac-sur-Mer et Montalivet-les-Bains, possède un riche patrimoine archéologique directement impacté par l’érosion littorale. Une succession de paléosols argilo-tourbeux appartenant à d’anciens marais littoraux recèle les témoignages d’une intense occupation depuis le Néolithique jusqu’à la fin de l’Antiquité. Les recherches se sont focalisées sur deux sites-clés : La Lède du Gurp (Grayan-et-l’Hôpital) et l’Amélie (Soulac-sur-Mer) où une approche interdisciplinaire fondée sur le croisement des données archéologiques, sédimentaires et paléoenvironnementales – au sens large du terme – a permis de replacer les principales phases de peuplement dans leur contexte environnemental. Ces travaux ont bénéficié d’une documentation de terrain exceptionnellement conservée dans des sédiments humides scellés sous le système dunaire actuel. Les traces les plus fugaces (empreintes) comme les aménagements anthropiques les plus robustes sont préservés, de même que de nombreux restes organiques. Ces éléments nous donnent accès à une documentation de premier ordre pour retracer la palette des activités pratiquées dans un écosystème spécifique : production du sel, pacage des animaux, agriculture, collecte des coquillages, circulation, pratiques funéraires et symboliques. L’étude du peuplement sur la longue durée révèle une alternance de phases dynamiques et de phases de déprise qui semblent corrélées avec les changements du milieu.

Published
2019

48. Changements côtiers holocènes le long de l’estuaire de la Gironde : nouvelles données à partir du système plage/dune de la péninsule du nord‑Médoc

Author

STÉPHAN, Pierre, VERDIN, Florence, ARNAUD-FASSETTA, Gilles, BERTRAND, Frédéric, EYNAUD, Frédérique, GARCÍA-ARTOLA, Ane, BOSQ, Mathieu, CULIOLI, Camille, SUANEZ, Serge, COUTELIER, Clément, BERTRAN, Pascal, and COSTA, Stéphane

Subjects
dune, marais maritimes, Gironde, estuaire, TLS, Aquitaine, vasière, Holocène, hausse du niveau marin, ensablement éolien
Published
2019

49. Holocene paleoenvironments over the last 9 kyr BP in the northeastern Atlantic Ocean: the Grande Vasiere deposit in the Bay of Biscay (NW France)

Author

Penaud, Aurélie, Ganne, A., Eynaud, Frédérique, Hardy, William, Herlédan, Maïwenn, Coste, Pierre-Olivier, Lambert, Clément, Nizou, Jean, Toucanne, Samuel, Bourrilet, Jean-Francois, Durand, Matthieu, Mojtahid, Meryem, Laboratoire Géosciences Océan (LGO), Université de Brest (UBO)-Université de Bretagne Sud (UBS)-Centre National de la Recherche Scientifique (CNRS)-Institut Français de Recherche pour l'Exploitation de la Mer - Brest (IFREMER Centre de Bretagne), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Laboratoire de recherche ARchéologie et Architecture (LARA), Université de Nantes (UN)-Centre de Recherche en Archéologie, Archéosciences, Histoire (CReAAH), Le Mans Université (UM)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC)-Nantes Université (NU)-Le Mans Université (UM)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC)-Nantes Université (NU), UMR 5805 Environnements et Paléoenvironnements Océaniques et Continentaux (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Domaines Océaniques (LDO), Centre National de la Recherche Scientifique (CNRS)-Institut d'écologie et environnement-Observatoire des Sciences de l'Univers-Université de Brest (UBO)-Institut national des sciences de l'Univers (INSU - CNRS), Institut Français de Recherche pour l'Exploitation de la Mer - Brest (IFREMER Centre de Bretagne), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Laboratoire Géodynamique et enregistrement Sédimentaire - Geosciences Marines (GM-LGS), Laboratoire de Planétologie et Géodynamique - Angers (LPG-ANGERS), Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), Université de Nantes (UN)-Le Mans Université (UM)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC)-Le Mans Université (UM)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC), Université de Bretagne Sud (UBS)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), Le Mans Université (UM)-Université de Rennes (UR)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Université de Nantes - UFR Histoire, Histoire de l'Art et Archéologie (UFR HHAA), Université de Nantes (UN)-Université de Nantes (UN)-Ministère de la Culture (MC)-Le Mans Université (UM)-Université de Rennes (UR)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Université de Nantes - UFR Histoire, Histoire de l'Art et Archéologie (UFR HHAA), Université de Nantes (UN)-Université de Nantes (UN)-Ministère de la Culture (MC), Environnements et Paléoenvironnements OCéaniques (EPOC), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Observatoire des Sciences de l'Univers-Institut d'écologie et environnement-Centre National de la Recherche Scientifique (CNRS), Laboratoire Géodynamique et enregistrement Sédimentaire (LGS), and Géosciences Marines (GM)

Subjects
[SDU]Sciences of the Universe [physics]
Published
2019

50. Millennial-scale Holocene hydrological changes in the northeast Atlantic: New insights from ‘ La Grande Vasière ’ mid-shelf mud belt

Author

Mojtahid, Meryem, Durand, Matthieu, Coste, Pierre-olivier, Toucanne, Samuel, Howa, Hélène, Nizou, Jean, Eynaud, Frédérique, Penaud, Aurélie, Mojtahid, Meryem, Durand, Matthieu, Coste, Pierre-olivier, Toucanne, Samuel, Howa, Hélène, Nizou, Jean, Eynaud, Frédérique, and Penaud, Aurélie

Abstract

A mid- to late-Holocene paleohydrological reconstruction from the northeast Atlantic is proposed through the study of a high-resolution sedimentary record from the northern continental shelf of the Bay of Biscay (BoB). Three foraminiferal species dominate the assemblages with Rosalina globularis showing an overall decrease in absolute and relative abundances from ~7 to 0.4 cal. ka BP, whereas the opposite trend is observed for Cibicides refulgens and Lobatula. These long-term patterns are interpreted as a response to the overall cooling trend and/or the progressive deepening of the water column because of the relative sea-level (RSL) rise. Foraminiferal δ18O and grain-size analyses show a significant shift around 3.5–2.5 cal. ka BP toward a heavier isotopic signature and finer sediments. We mainly link this change to enhanced contribution of continental freshwaters and fine sediments after the near-stabilization of the RSL rise. By reducing coastal accommodation spaces, this led to a better channelization of river outflows and probably to the formation of the modern winter thermohaline front. Superimposed on these long-term patterns, our data highlight strong millennial-scale variability (1250-year peak). Such cyclicity is consistent with several records tracing changes in rainfall and storminess regimes in northern Europe, and the dynamics of the subpolar gyre (SPG). We suggest a millennial time-scale control of a NAO-like (North Atlantic Oscillation) climatic process modulating continental humidity (and the associated river discharges) and SPG dynamics through wind stress. Spectral analyses reveal an additional 500-year frequency peak implying a possible solar forcing.

Published
2019
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results