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Arnaud, Fabien; Revillon, Sidonie; Debret, Maxime; Revel, Marie; Chapron, Emmanuel; Jacob, Jeremy; Giguet-covex, Charline; Poulenard, Jerome; Magny, Michel. |
Two well-dated ca Holocene-long sedimentary sequences from deepest parts of Lake Bourget provide new insights onto the evolution of erosion patterns at a regional scale in NW European Alps. The combination of high resolution geochemistry - XRF core scanning, calibrated by 150 punctual measurements - and isotope geochemistry (epsilon Nd) of the terrigenous fraction permitted the reconstruction not only of the intensity, but also the type (physical erosion vs. chemical weathering) and the location (Prealpine massifs vs. High Crystalline massifs) of dominant erosion processes. Those data point the persistency of weak erosion fluxes from 9600 to 5500 cal. BP due both to a dry climate and the growing sheltering effect of soils that rapidly progressed between... |
Tipo: Text |
Palavras-chave: Holocene; Alps; Erosion; Soil dynamics; Paleohydrology. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00106/21723/20064.pdf |
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Van Der Putten, Nathalie; Verbruggen, Cyriel; Bjorck, Svante; Michel, Elisabeth; Disnar, Jean-robert; Chapron, Emmanuel; Moine, Bertrand N.; De Beaulieu, Jacques-louis. |
The awareness of the significance of the Southern Ocean in the Earth's climate system has become increasingly obvious. The deglacial atmospheric CO2 rise during warming periods in Antarctica has been attributed to CO2 ventilation from the deep ocean caused by enhanced upwelling around the Antarctic Divergence. It has been hypothesized that, more intense Southern Hemisphere westerly winds aligned with the Antarctic Circumpolar Current due to a southward shift of the wind belt from its Last Glacial Maximum equator-ward position, are the main drivers. Reconstructions of past changes in atmospheric circulation in the Southern Hemisphere are still scarce and the overall picture is patchy with sometimes contradictory results. For obvious reasons, most... |
Tipo: Text |
Palavras-chave: Palaeoclimatology; Last Termination; Peat record; Kerguelen Islands; Southern Ocean; Indian Ocean; Oceanic Cold Reversal; Southern Hemisphere westerly belt. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00497/60843/64283.pdf |
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Magny, Michel; Combourieu Nebout, Nathalie; De Beaulieu, Jacques-louis; Bout-roumazeilles, Viviane; Colombaroli, D.; Desprat, Stephanie; Francke, A.; Joannin, Sebastien; Ortu, Elena; Peyron, Odile; Revel, Marie; Sadori, Laura; Siani, Giuseppe; Sicre, Marie-alexandrine; Samartin, S.; Simonneau, A.; Tinner, Willy; Vanniere, Boris; Wagner, B.; Zanchetta, Giovanni; Anselmetti, Flavio S.; Brugiapaglia, E.; Chapron, Emmanuel; Debret, Maxime; Desmet, Marc; Didier, Jean; Essallami, Latifa; Galop, D.; Gilli, A.; Haas, J.n.; Kallel, Nejib; Millet, L.; Stock, Andy; Turon, Jean-louis; Wirth, S.. |
On the basis of a multi-proxy approach and a strategy combining lacustrine and marine records along a north-south transect, data collected in the central Mediterranean within the framework of a collaborative project have led to reconstruction of high-resolution and well-dated palaeohydrological records and to assessment of their spatial and temporal coherency. Contrasting patterns of palaeohydrological changes have been evidenced in the central Mediterranean: south (north) of around 40 degrees N of latitude, the middle part of the Holocene was characterised by lake-level maxima (minima), during an interval dated to ca. 10 300-4500 cal BP to the south and 9000-4500 cal BP to the north. Available data suggest that these contrasting palaeohydrological... |
Tipo: Text |
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Ano: 2013 |
URL: https://archimer.ifremer.fr/doc/00264/37570/36902.pdf |
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