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dc.contributor.authorStevens, Thomas
dc.contributor.authorSechi, Daniele
dc.contributor.authorBradák, Balázs
dc.contributor.authorOrbe, Ragna
dc.contributor.authorBaykal, Yunus
dc.contributor.authorCossu, Giulia
dc.contributor.authorTziavaras, Charilaos
dc.contributor.authorAndreucci, Stefano
dc.contributor.authorPascucci, Vincenzo
dc.date.accessioned2021-11-04T12:56:52Z
dc.date.available2021-11-04T12:56:52Z
dc.date.issued2020-12
dc.identifier.issn0277-3791
dc.identifier.urihttp://hdl.handle.net/10259/6103
dc.description.abstractLoess deposits in southern Britain contain a record of dust, climate and landscape dynamics over the last glacial, yet their age and accumulation rate remain poorly known. Furthermore, the environmental controls on the loess-soil stratigraphy shown in the thickest deposits in southeast England are still debated. Here we apply the first high sampling resolution quartz optically stimulated luminescence study of dust accumulation and loess formation in Britain at the Pegwell Bay site in east Kent. We couple this to mineral magnetic, particle size and geochemical analyses to understand climate, environment and post depositional modification of the loess. The luminescence ages and Bayesian age modelling results suggest two phases of greatly enhanced dust accumulation at the site. Loess began to accumulate around c. 25e23.5 ka, coinciding with Heinrich event 2, and after subsequent lower accumulation rates, a second enhanced phase of deposition occurred at around 20e19 ka.We propose a model where the dynamics of the British-Irish and Fennoscandian Ice Sheets, associated glacial lake drainage, and linked reorganisations of atmospheric circulation, all controlled loess accumulation in southern Britain. Accumulation in the first phase was triggered by increased sediment supply from initial retreat of the North Sea ice lobe, and drainage of Dogger Lake. Loess accumulation during this phase was enhanced by easterly winds from Atlantic depressions tracking to the south of Britain, caused by the maximum extent of the Irish Sea Ice Stream at c. 25e24 ka. The subsequent retreat of the western part of the British Irish Ice Sheet then allowed storm tracking further north, which reduced effectiveness of dust transporting winds across southern Britain, while sediment supply and availability was reduced in North Sea source areas. A second retreat of the maximum extent of the North Sea Lobe of ice after c. 21e20 ka would have led to another abrupt input of sediment-rich ice dammed lake and meltwater from eastern England and the North Sea into the exposed southern North Sea area. This would have again dramatically increased sediment availability for transport and deposition as loess in SE England, resulting in the second dust accumulation phase. We also propose that the abrupt stratigraphic change from calcareous to non-calcareous loess up section at Pegwell Bay was driven, not by these changes in dust input, but rather deepening of the permafrost active layer after c. 21 ka. This deepening was associated with warmer and wetter conditions driven by Atlantic storms tracking further north following the regression of the Irish Sea Ice Stream and overall ice sheet retreat. As such, last glacial dust dynamics and loess accumulation in Britain is highly influenced by the interaction of the British Irish Ice Sheet the Fennoscandian Ice sheet, Atlantic storm tracks, and the topography and drainage of the exposed North Sea.en
dc.description.sponsorshipSwedish Research Council (VR grant 2017e03888) and the Quaternary Research Association (QRA) Quaternary Research Fund. BB acknowledges the financial support of project BU235P18 (Junta de Castilla y Leon, Spain) and the European Regional Development Fund (ERD).en
dc.format.mimetypeapplication/pdf
dc.language.isoenges
dc.publisherElsevier
dc.relation.ispartofQuaternary Science Reviews. 2020, V. 250, 106641en
dc.rightsAtribución 4.0 Internacional*
dc.rights.urihttp://creativecommons.org/licenses/by/4.0/*
dc.subjectLoessen
dc.subjectPegwell bayen
dc.subjectLuminescenceen
dc.subjectMulti-proxyen
dc.subjectBrickearthen
dc.subjectPalaeoenvironmenten
dc.subject.otherFísicaes
dc.subject.otherPhysicsen
dc.subject.otherCiencias medioambientaleses
dc.subject.otherEnvironmental sciencesen
dc.subject.otherGeología
dc.subject.otherGeology
dc.titleAbrupt last glacial dust fall over southeast England associated with dynamics of the British-Irish ice sheeten
dc.typeinfo:eu-repo/semantics/articlees
dc.rights.accessRightsinfo:eu-repo/semantics/openAccesses
dc.relation.publisherversionhttps://doi.org/10.1016/j.quascirev.2020.106641
dc.identifier.doi10.1016/j.quascirev.2020.106641
dc.type.hasVersioninfo:eu-repo/semantics/publishedVersiones


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