Eurasian Ice Sheet derived meltwater pulses and their role in driving atmospheric dust activity: Late Quaternary loess sources in SE England

• Published in: Quaternary Science Reviews
• Main Authors: Baykal, Yunus, Stevens, Thomas, Bateman, Mark D., Pfaff, Katharina, Sechi, Daniele, Banak, Adriano, Šuica, Sanja, Zhang, Haobo, Nie, Junsheng
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier BV 2022
• Subjects: Provenance; Detrital zircon U-Pb ages; Heavy minerals; Nd isotopes; Quartz grain morphology; Pegwell Bay; Fennoscandian; Ice Sheet
• Online Access: https://archimer.ifremer.fr/doc/00798/90990/96657.pdf; https://archimer.ifremer.fr/doc/00798/90990/96658.xlsx; https://archimer.ifremer.fr/doc/00798/90990/96659.xlsx; https://archimer.ifremer.fr/doc/00798/90990/96660.docx; https://doi.org/10.1016/j.quascirev.2022.107804; https://archimer.ifremer.fr/doc/00798/90990/

The role of Quaternary ice sheet fluctuations in driving meltwater pulses and ocean circulation perturbations is widely acknowledged. What is less clear is the role of these processes in driving changes in past atmospheric dust activity, and possible wider links between dust and climate. Terrestrial windblown dust (loess) deposits along the northern fringe of the European loess belt potentially record past atmospheric dust emission from regions close to the former Eurasian Ice Sheet (EIS) and provide a means to evaluate the role of ice sheet fluctuations in the past dust cycle. Numerical loess chronologies across this region generally agree on greatly enhanced dust deposition rates during MIS 2, when the EIS reached its maximum extent. Yet, uncertainties over the sources of this material prevent understanding of the precise causes of this greatly enhanced atmospheric dustiness, and any potential link to ice sheet fluctuations and climate. In southeast England, loess accumulation dominantly occurred in two phases centered on 25–23.5 ka and 20–19 ka, matching the timing of coalescence of the Fennoscandian and British-Irish ice sheets and specifically advances and retreats of nearby ice lobes in the western North Sea. As such, these deposits provide an ideal test of the role of ice sheet fluctuations in atmospheric dust dynamics. Here we undertake such a test through a detailed provenance study of loess in southeast England and potential dust source sediments across the North Sea region. We group extensive new and published data sets of detrital zircon U–Pb ages from basement rocks and Cenozoic sediments in the North Sea area, which not only provide new insight into both loess source, but also the nature of sediment transport over NW Europe into the North Sea basin more widely. Multi-proxy evidence allows us to unambiguously identify ice sheet derived sediments in the exposed North Sea basin as the dominant source of loess in southeast England, while fluvial sediments delivered by rivers draining Continental Europe ...