High-elevation cosmogenic nuclide dating of the last deglaciation in the central Swedish mountains: implications for the timing of tree establishment
(English)Manuscript (preprint) (Other academic)
We use cosmogenic exposure ages to determine the timing of deglaciation of the Scandinavian ice sheet (SIS) at summit elevation in the central Swedish mountains. Mean exposure ages for boulders on the summit of Mt. Åreskutan (10.6 ±0.6 ka, n = 3, 1420 m a.s.l.) and from the highest-elevation moraine related to SIS deglaciation in Sweden (12.0 ±0.6 ka, n = 3, 1135 m a.s.l.) are consistent with previous lower-elevation radiocarbon age estimates for the timing of deglaciation. Summit areas in this region deglaciated ~12.0-10.6 ka, coinciding approximately with the termination of the Younger Dryas cold interval (11.7 ka). Unusually old radiocarbon ages of tree remains previously studied from the summit-area of Mt. Åreskutan are rejected on the basis of incompatibility with consistent TCN ages for deglaciation, and incompatibility with established paleoecological and paleoglaciological reconstructions. Analysis of the new exposure ages against radiocarbon ages from lower elevation indicates that the SIS decayed rapidly during final deglaciation.
cosmogenic exposure dating, radiocarbon dating, moraine, deglaciation, nunatak
Research subject Quarternary Geology
IdentifiersURN: urn:nbn:se:su:diva-38797OAI: oai:DiVA.org:su-38797DiVA: diva2:315350