Middle-Late Pleistocene landscape evolution of the Dover Strait inferred from buried and submerged erosional landforms

QUATERNARY SCIENCE REVIEWS

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Article

Garcia-Moreno, David^1,2  Gupta, Sanjeev³  Collier, Jenny S.³  Oggioni, Francesca³  Vanneste, Kris²  Trentesaux, Alain⁴  Verbeeck, Koen²  Versteeg, Wim⁵  Jomard, Herve⁶  Camelbeeck, Thierry²  De Batist, Marc¹ 

[1] Univ Ghent, Dept Geol, Campus Sterre,Bldg S8,Krijgslaan 281, B-9000 Ghent, Belgium

[2] Royal Observ Belgium, Ave Circulaire 3, B-1180 Brussels, Belgium

[3] Imperial Coll London, Dept Earth Sci & Engn, Prince Consort Rd, London SW7 2BP, England

[4] Univ Lille 1, LOG, UMR 8187, F-59650 Villeneuve Dascq, France

[5] VLaams Inst Zee, InnovOcean Site,Wandelaarkaai 7, B-8400 Oostende, Belgium

[6] Inst Radioprotect & Surete Nucl, Ave Div Leclerc 31, F-92260 Fontenay Aux Roses, France

关键词: Geomorphology;    Pleistocene;    Palaeogeography;    Megaflood;    Western Europe;   

DOI  :  10.1016/j.quascirev.2018.11.011

来源: Elsevier

【 摘 要 】

Prominent landforms, either buried or preserved at the seafloor, provide important constraints on the processes that led to the opening and present-day configuration of the Dover Strait. Here, we extend previous investigations on two distinct landform features, the Fosse Dangeard and Lobourg Channel, to better understand the poly-phase history of their formation and inferences for the opening and Pleistocene evolution of the Dover Strait. The Fosse Dangeard consist of several interconnected palaeo-depressions. Their morphology and spatial distribution are interpreted to be the result of plunge-pool erosion generated at the base of north-eastward retreating waterfalls. Their infills comprise internal erosional surfaces that provide evidence for the occurrence of several erosional episodes following their initial incision. The Lobourg Channel comprises various sets of erosional features, attesting to the occurrence of several phases of intense fluvial and/or flood erosion. The last one of these carved a prominent inner channel, which truncates the uppermost infill of the Fosse Dangeard. The morphology of the Lobourg inner channel and the erosional features associated with its incision strongly resemble landforms found in megaflood-eroded terrains, indicating that this valley was likely eroded by one or several megafloods. Our study therefore corroborates the existence of waterfalls in the Dover Strait at least once during the Pleistocene Epoch. It also provides evidence of the occurrence of multiple episodes of fluvial and flood erosion, including megafloods. Finally, this study allows us to establish a relative chronology of the erosional/depositional episodes that resulted in the present-day morphology of this region. (C) 2018 Elsevier Ltd. All rights reserved.

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