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| Toucanne, Samuel; Zaragosi, S.; Bourillet, Jean-francois; Gibbard, P. L.; Eynaud, F.; Giraudeau, J.; Turon, J. L.; Cremer, M.; Cortijo, E.; Martinez, P.; Rossignol, L.. |
| The correlation of continental sedimentary records with the marine isotope stratigraphy is a challenge of central importance in Quaternary stratigraphy, particularly in Western Europe where long records of glaciation on land areas are particularly rare. Here we demonstrate for the first time the interrelationship of events during the last 1.2 Ma in an ocean-sediment core from the Bay of Biscay (NE Atlantic), SW of the Channel. The identification of discharge variations from tributary river systems to the 'Fleuve Manche' palaeoriver during glacio-eustatic sea-level lowstands demonstrates the correlation of the marine sediment stratigraphy to the expansion and recession of the European ice-sheets. The amplitude and chronology of European ice-sheet... |
| Tipo: Text |
Palavras-chave: Middle pleistocene transition; Ice sheet dynamics; Sea level; Climate change; North Atlantic; English channel; Heinrich events; Fleuve manche; Deep; Origin. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6956.pdf |
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| Penaud, Aurelie; Eynaud, F.; Voelker, A.; Kageyama, M.; Marret, F.; Turon, J. L.; Blamart, D.; Mulder, T.; Rossignol, L.. |
| New dinocyst analyses were conducted on core MD99-2339 retrieved from the central Gulf of Cadiz. Dinocyst and foraminiferal assemblages from this core are combined with existing data off SW Portugal and NW Morocco to investigate past hydrological and primary productivity regimes in the subtropical NE Atlantic Ocean over the last 30 ka. Our results have revealed highest upwelling intensity during Heinrich Stadial 1 (HS 1) and the Younger Dryas and weaker upwelling cells during the Last Glacial Maximum (LGM) and HS 2, off the SW Iberian and NW Moroccan margins. Similar assemblages between the Gulf of Cadiz and the NW Moroccan margin, and distinct species off Portugal, were observed during the cold climatic extremes that punctuated the last 30 ka. This... |
| Tipo: Text |
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| Ano: 2011 |
URL: https://archimer.ifremer.fr/doc/00230/34125/32598.pdf |
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| Desprat, S.; Combourieu-nebout, N.; Essallami, L.; Sicre, Marie-alexandrine; Dormoy, I.; Peyron, O.; Siani, G.; Roumazeilles, V. Bout; Turon, J. L.. |
| Despite a large number of studies, the long-term and millennial to centennial-scale climatic variability in the Mediterranean region during the last deglaciation and the Holocene is still debated, including in the southern Central Mediterranean. In this paper, we present a new marine pollen sequence (core MD04-2797CQ) from the Siculo-Tunisian Strait documenting the regional vegetation and climatic changes in the southern Central Mediterranean during the last deglaciation and the Holocene. The MD04-2797CQ marine pollen sequence shows that semi-desert plants dominated the vegetal cover in the southern Central Mediterranean between 18.2 and 12.3 ka cal BP, indicating prevailing dry conditions during the deglaciation, even during the Greenland Interstadial... |
| Tipo: Text |
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| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00181/29241/27634.pdf |
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| Toucanne, Samuel; Zaragosi, S.; Bourillet, Jean-francois; Cremer, M.; Eynaud, Frederique; Van Vliet-lanoe, B.; Penaud, A.; Fontanier, C.; Turon, J. L.; Cortijo, E.; Gibbard, P. L.. |
| Continuous high-resolution mass accumulation rates (MAR) and X-ray fluorescence (XRF) measurements from marine sediment records in the Bay of Biscay (NE Atlantic) have allowed the determination of the timing and the amplitude of the ‘Fleuve Manche’ (Channel River) discharges during glacial stages MIS 10, MIS 8, MIS 6 and MIS 4–2. These results have yielded detailed insight into the Middle and Late Pleistocene glaciations in Europe and the drainage network of the western and central European rivers over the last 350 kyr. This study provides clear evidence that the ‘Fleuve Manche’ connected the southern North Sea basin with the Bay of Biscay during each glacial period and reveals that ‘Fleuve Manche’ activity during the glaciations MIS 10 and MIS 8 was... |
| Tipo: Text |
Palavras-chave: Northern north sea; Late weichselian glaciation; Western iberian margin; Abrupt climate change; C 14 YR BP; Deep sea; Heinrich events; Norwegian margin; Millennial scale; English channel. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00011/12261/9037.pdf |
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| Mazaud, A.; Kissel, C.; Laj, C.; Sicre, M. A.; Michel, E.; Turon, J. L.. |
| We examine the magnetic mineral deposition in three cores located at midlatitude sites in the South Indian Ocean, in an area where sediment eroded from the Kerguelen-Crozet plateau and transported by the marine currents, principally the Antarctic Circum Current, accumulates at a high sedimentation rate. We focus on Marine Isotopic Stage 3, characterized by large climatic fluctuations at northern latitudes, and compare the obtained records to the climatic records at Byrd ( Antarctica) and Summit (GISP2, Greenland) and to the North Atlantic Deep Water variations in the North Atlantic. Magnetic mineral deposition at the studied sites exhibits a profile with maxima at the time of Heinrich events H4 and H5, which suggests a strong Antarctic Circum Current when... |
| Tipo: Text |
Palavras-chave: Paleoceanography; South; Indian; Ocean; Paleoclimatology and paleoceanography; Environmental magnetism; Interhemispheric phasing. |
| Ano: 2007 |
URL: https://archimer.ifremer.fr/doc/00235/34612/32954.pdf |
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| Mazaud, A.; Michel, Elisabeth; Dewilde, F.; Turon, J. L.. |
| We examine the past variations of the Antarctic Circumpolar Current (ACC) by using variations in size and abundance of the magnetic grains deposited by this current at a site east the Kerguelen-Crozet plateau. Core MD00-2375G was taken at a midlatitude site during the ANTAUS cruise conducted in 2000 by the French R/V Marion Dufresne. Marine isotope stages (MIS) down to MIS 13 are identified, and an age model is derived from a correlation to the ice core isotopic record obtained from EPICA in Antarctica. Continuous records of abundance and size of the magnetic grains were obtained using environmental magnetism methods. Results show a strong modulation of the ACC flow intensity in response to glacial and interglacial cycles. The low abundance and the small... |
| Tipo: Text |
Palavras-chave: Antarctic; Current; Past; Cycles. |
| Ano: 2010 |
URL: https://archimer.ifremer.fr/doc/00231/34190/32874.pdf |
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| Penaud, A.; Eynaud, F.; Turon, J. L.; Zaragosi, S.; Malaize, B.; Toucanne, Samuel; Bourillet, Jean-francois. |
| We present a new marine palynological record from the temperate North-eastern Atlantic (core MD03-2692, Celtic-Armorican margin) in the area of influence of the 'Fleuve Manche' paleoriver during glacial times. The runoff of this paleoriver was connected to the glacial history of European ice sheets (including the British Irish Ice Sheet-BIIS). Our study conducted on dinoflagellate cysts assemblages over the last 200 ka, associated with quantification of palynological remains reflecting continental influence (pre-Quaternary dinocysts and micro-algae Pediastrum spp. coenobia), yields detailed insights into the sea-surface paleoenvironments of this sector. More specifically, mechanisms responsible for the origin of unusual deposits of laminated sequences... |
| Tipo: Text |
Palavras-chave: Dinoflagellate cysts; European ice sheets; Celtic Armorican margin; MIS 2 and MIS 6; Terminations I and II. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00000/11116/8061.pdf |
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