A regional assessment of the deglaciation history of the Swiss Plateau based on newly obtained and re-evaluated Be-10 cosmic-ray exposure ages
Hofmann FM, Groos AR, Garcia Morabito E, Struck J, Gnägi C, Scharf A, Rugel G, Merchel S, Zech R (2023)
Publication Type: Journal article, Original article
Publication year: 2023
Journal
Book Volume: 13
Pages Range: 1-17
DOI: 10.1016/j.qsa.2023.100124
Open Access Link: https://doi.org/10.1016/j.qsa.2023.100124
Abstract
During marine oxygen isotope stage (MIS) 2, the Swiss Plateau temporarily hosted large piedmont lobe glaciers that retreated after their maximum advance back to the fringe of the Alps. The presence of moraines in this region indicates that overall glacier recession was punctuated by repeated phases of ice-marginal stability and re-advances. The timing of these events in the region formerly covered by the eastern lobe of the Rhône (or Valais) glacier has been controversial and remains poorly constrained due to the lack of chronological data. To fill this gap, 10 Be cosmic-ray exposure (CRE) dating was applied to erratic boulders inside the assumed MIS 2 maximum extent of this piedmont lobe. An erratic boulder at an ice-marginal position upstream from the suspected MIS 2 maximum extent gave an age of about 19 ka. Erratic boulders at a presumably younger ice-marginal position (Brästenberg position) yielded an average age of ca. 20 ka. However, several erratic boulders beyond the Brästenberg position gave internally consistent, but stratigraphically too young ages of ca. 17 ka. We cannot rule out that glacier recession from the Brästenberg position began no later than 17 ka. CRE dating of a moraine of a presumably younger ice-marginal position (Solothurn position) gave unrealistically old ages and an incredibly young age (86 ka, 40 ka, and 4 ka). Carbon-14 CRE dating should be applied to provide additional information on the last deglaciation of the Swiss Plateau. Nevertheless, despite outlying ages, the presented chronological data contribute to an overall consistent and increasingly refined chronology of the last deglaciation of the Swiss Plateau when compared with 59 previously published CRE ages.
Authors with CRIS profile
Involved external institutions
weg>punkt - Dr. Christian Gnägi
Switzerland (CH)
Albert-Ludwigs-Universität Freiburg
Germany (DE)
Universität Bern
Switzerland (CH)
Helmholtz-Zentrum Dresden-Rossendorf (HZDR)
Germany (DE)
Friedrich-Schiller-Universität Jena
Germany (DE)
Universität Wien / University of Vienna
Austria (AT)
Switzerland (CH)
Albert-Ludwigs-Universität Freiburg
Germany (DE)
Universität Bern
Switzerland (CH)
Helmholtz-Zentrum Dresden-Rossendorf (HZDR)
Germany (DE)
Friedrich-Schiller-Universität Jena
Germany (DE)
Universität Wien / University of Vienna
Austria (AT)
How to cite
APA:
Hofmann, F.M., Groos, A.R., Garcia Morabito, E., Struck, J., Gnägi, C., Scharf, A.,... Zech, R. (2023). A regional assessment of the deglaciation history of the Swiss Plateau based on newly obtained and re-evaluated Be-10 cosmic-ray exposure ages. Quaternary Science Advances, 13, 1-17. https://dx.doi.org/10.1016/j.qsa.2023.100124
MLA:
Hofmann, Felix Martin, et al. "A regional assessment of the deglaciation history of the Swiss Plateau based on newly obtained and re-evaluated Be-10 cosmic-ray exposure ages." Quaternary Science Advances 13 (2023): 1-17.
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