Percorrer por autor "Bard, Edouard"
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- A C-14 chronology for the Middle to Upper Palaeolithic transition at Bacho Kiro Cave, BulgariaPublication . Fewlass, Helen; Talamo, Sahra; Wacker, Lukas; Kromer, Bernd; Tuna, Thibaut; Fagault, Yoann; Bard, Edouard; McPherron, Shannon P.; Aldeias, Vera; Maria, Raquel; Martisius, Naomi L.; Paskulin, Lindsay; Rezek, Zeljko; Sinet-Mathiot, Virginie; Sirakova, Svoboda; Smith, Geoffrey M.; Spasov, Rosen; Welker, Frido; Sirakov, Nikolay; Tsanova, Tsenka; Hublin, Jean-JacquesThe stratigraphy at Bacho Kiro Cave, Bulgaria, spans the Middle to Upper Palaeolithic transition, including an Initial Upper Palaeolithic (IUP) assemblage argued to represent the earliest arrival of Upper Palaeolithic Homo sapiens in Europe. We applied the latest techniques in C-14 dating to an extensive dataset of newly excavated animal and human bones to produce a robust, high-precision radiocarbon chronology for the site. At the base of the stratigraphy, the Middle Palaeolithic (MP) occupation dates to >51,000 yr bp. A chronological gap of over 3,000 years separates the MP occupation from the occupation of the cave by H. sapiens, which extends to 34,000 cal bp. The extensive IUP assemblage, now associated with directly dated H. sapiens fossils at this site, securely dates to 45,820-43,650 cal bp (95.4% probability), probably beginning from 46,940 cal bp (95.4% probability). The results provide chronological context for the early occupation of Europe by Upper Palaeolithic H. sapiens. A new radiocarbon chronology for the Middle to Upper Palaeolithic transition at the Bulgarian site of Bacho Kiro reveals Homo sapiens-associated sediments as early as 46,940 yr bp.
- Marine Isotope Stage 4 (71–57 ka) on the Western European margin: insights to the drainage and dynamics of the Western European Ice SheetPublication . Toucanne, Samuel; Rodrigues, Teresa; Menot, Guillemette; Soulet, Guillaume; Cheron, Sandrine; Billy, Isabelle; Eynaud, Frederique; Antoine, Pierre; Sinninghe Damste, Jaap S.; Bard, Edouard; Sanchez Goñi, Maria-FernandaMarine Isotope Stage (MIS) 4 (ca. 71–57 ka; within the Middle Weichselian Substage) is considered a significant Pleistocene glaciation, but it remains poorly constrained in comparison to that of the Late Weichselian Last Glacial Maximum (LGM; ca. 29–19 ka, during MIS 2), or even the Late Saalian MIS 6 (ca. 190–130 ka). Most MIS 4 glacial landforms in Europe were erased by the more extensive LGM ice advance, precluding a robust recon struction of its extent and dynamic through time. Marine sedimentary archives, in preserving the source-to-sink sediment transfer signals of ice-sheet and glacier processes, help to bridge this gap. Here, the signals west of the European Ice Sheet (EIS) are tracked for MIS 4 from the deep Bay of Biscay (NE Atlantic), which was the outlet for Fennoscandian Ice Sheet (FIS) sediment-laden meltwater during extensive glaciations, specifically when the British-Irish Ice Sheet (BIIS) and the FIS coalesced into the North Sea (as during MIS 6 and the LGM). Sedi mentological, geochemical, and mineralogical proxies reveal the absence of FIS-derived material in Bay of Biscay sediment throughout MIS 4, which indicates that FIS meltwater and huge river systems from the North European Plain never drained into the Bay of Biscay at that time. This suggests that contrary to MIS 6 and the LGM, the BIIS and FIS were not likely large enough to coalesce and form a (grounded) ice bridge onto the North Sea, thus confirming geomorphic evidence for a significant, but relatively limited, glaciation in Europe during MIS 4. Closer to the Bay of Biscay, ice-marginal fluctuations of the BIIS are identified in the Celtic-Irish Sea region from the deep-sea record. More specifically, our findings suggest an early retreat of the Irish Sea Ice Stream as soon as ca. 68–65 ka, a few millennia before the demise of the EIS, and the Northern Hemisphere ice sheets as a whole, during Heinrich Stadial (HS) 6. This pattern is similar to that already recorded during MIS 2. Finally, this study reveals that the MIS 4 period in Western Europe corresponds, as for MIS 2, to a complex combination of general ice advance interspersed by preliminary-to-final EIS demises highlighted by HS conditions.