Constraints from cosmogenic nuclides on the glaciation and erosion history of Dove Bugt, northeast Greenland
The intricate interplay between subglacial topography and ice-sheet dynamics is key to the evolution of large ice sheets, but in Greenland as elsewhere the effects of longterm glacial history on landscape evolution remain poorly constrained. Here we measure abundances of cosmogenic 10 Be and 26 Al i...
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ftcopenhagenunip:oai:pure.atira.dk:publications/59c29bc4-e45e-4875-9f6c-32dcd304fa29 2024-04-21T08:01:03+00:00 Constraints from cosmogenic nuclides on the glaciation and erosion history of Dove Bugt, northeast Greenland Skov, Daniel Søndergaard Andersen, J. L. Olsen, J. Jacobsen, B. H. Knudsen, M. F. Jansen, J. D. Larsen, N. K. Egholm, D. L. 2020 https://curis.ku.dk/portal/da/publications/constraints-from-cosmogenic-nuclides-on-the-glaciation-and-erosion-history-of-dove-bugt-northeast-greenland(59c29bc4-e45e-4875-9f6c-32dcd304fa29).html https://doi.org/10.1130/b35410.1 eng eng info:eu-repo/semantics/closedAccess Skov , D S , Andersen , J L , Olsen , J , Jacobsen , B H , Knudsen , M F , Jansen , J D , Larsen , N K & Egholm , D L 2020 , ' Constraints from cosmogenic nuclides on the glaciation and erosion history of Dove Bugt, northeast Greenland ' , Bulletin of the Geological Society of America , vol. 132 , no. 11-12 , pp. 2282-2294 . https://doi.org/10.1130/b35410.1 article 2020 ftcopenhagenunip https://doi.org/10.1130/b35410.1 2024-04-11T00:22:41Z The intricate interplay between subglacial topography and ice-sheet dynamics is key to the evolution of large ice sheets, but in Greenland as elsewhere the effects of longterm glacial history on landscape evolution remain poorly constrained. Here we measure abundances of cosmogenic 10 Be and 26 Al in bedrock and transported boulders to unveil the glaciation and erosion history of Dove Bugt, northeast Greenland. In agreement with studies of west Greenland, we find that apparent exposure ages increase with elevation from 9 ka to 13 ka in low-lying valleys to 21 ka to 204 ka on high-elevation, blockfieldcovered plateaus. We employ a Markov chain Monte Carlo inversion framework to constrain the probability of various erosion histories, and we quantify the residence time of samples within the upper 2 m of the bedrock subsurface—a measure defined as the cosmogenic nuclide memory. This cosmogenic nuclide memory exceeds 600 ka on the highest plateaus but is limited to less than 500 ka in most other high-elevation samples and to less than 100 ka at low-elevations. Our results define maximum limits for the fraction of ice cover during the past 1 Ma to ~70% on the Store Koldewey peaks and ~90% farther inland at Pusterdal, respectively. Minimum limits to ice cover, however, cannot be reliably constrained by the data. Finally, we propose that limited erosion on the highest plateaus of Store Koldewey since 0.6–1.0 Ma indicates a minimum age for fjord-plateau formation within this area of northeast Greenland. Article in Journal/Newspaper Dove bugt Greenland Ice Sheet Store koldewey University of Copenhagen: Research GSA Bulletin 132 11-12 2282 2294 |
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Open Polar |
collection |
University of Copenhagen: Research |
op_collection_id |
ftcopenhagenunip |
language |
English |
description |
The intricate interplay between subglacial topography and ice-sheet dynamics is key to the evolution of large ice sheets, but in Greenland as elsewhere the effects of longterm glacial history on landscape evolution remain poorly constrained. Here we measure abundances of cosmogenic 10 Be and 26 Al in bedrock and transported boulders to unveil the glaciation and erosion history of Dove Bugt, northeast Greenland. In agreement with studies of west Greenland, we find that apparent exposure ages increase with elevation from 9 ka to 13 ka in low-lying valleys to 21 ka to 204 ka on high-elevation, blockfieldcovered plateaus. We employ a Markov chain Monte Carlo inversion framework to constrain the probability of various erosion histories, and we quantify the residence time of samples within the upper 2 m of the bedrock subsurface—a measure defined as the cosmogenic nuclide memory. This cosmogenic nuclide memory exceeds 600 ka on the highest plateaus but is limited to less than 500 ka in most other high-elevation samples and to less than 100 ka at low-elevations. Our results define maximum limits for the fraction of ice cover during the past 1 Ma to ~70% on the Store Koldewey peaks and ~90% farther inland at Pusterdal, respectively. Minimum limits to ice cover, however, cannot be reliably constrained by the data. Finally, we propose that limited erosion on the highest plateaus of Store Koldewey since 0.6–1.0 Ma indicates a minimum age for fjord-plateau formation within this area of northeast Greenland. |
format |
Article in Journal/Newspaper |
author |
Skov, Daniel Søndergaard Andersen, J. L. Olsen, J. Jacobsen, B. H. Knudsen, M. F. Jansen, J. D. Larsen, N. K. Egholm, D. L. |
spellingShingle |
Skov, Daniel Søndergaard Andersen, J. L. Olsen, J. Jacobsen, B. H. Knudsen, M. F. Jansen, J. D. Larsen, N. K. Egholm, D. L. Constraints from cosmogenic nuclides on the glaciation and erosion history of Dove Bugt, northeast Greenland |
author_facet |
Skov, Daniel Søndergaard Andersen, J. L. Olsen, J. Jacobsen, B. H. Knudsen, M. F. Jansen, J. D. Larsen, N. K. Egholm, D. L. |
author_sort |
Skov, Daniel Søndergaard |
title |
Constraints from cosmogenic nuclides on the glaciation and erosion history of Dove Bugt, northeast Greenland |
title_short |
Constraints from cosmogenic nuclides on the glaciation and erosion history of Dove Bugt, northeast Greenland |
title_full |
Constraints from cosmogenic nuclides on the glaciation and erosion history of Dove Bugt, northeast Greenland |
title_fullStr |
Constraints from cosmogenic nuclides on the glaciation and erosion history of Dove Bugt, northeast Greenland |
title_full_unstemmed |
Constraints from cosmogenic nuclides on the glaciation and erosion history of Dove Bugt, northeast Greenland |
title_sort |
constraints from cosmogenic nuclides on the glaciation and erosion history of dove bugt, northeast greenland |
publishDate |
2020 |
url |
https://curis.ku.dk/portal/da/publications/constraints-from-cosmogenic-nuclides-on-the-glaciation-and-erosion-history-of-dove-bugt-northeast-greenland(59c29bc4-e45e-4875-9f6c-32dcd304fa29).html https://doi.org/10.1130/b35410.1 |
genre |
Dove bugt Greenland Ice Sheet Store koldewey |
genre_facet |
Dove bugt Greenland Ice Sheet Store koldewey |
op_source |
Skov , D S , Andersen , J L , Olsen , J , Jacobsen , B H , Knudsen , M F , Jansen , J D , Larsen , N K & Egholm , D L 2020 , ' Constraints from cosmogenic nuclides on the glaciation and erosion history of Dove Bugt, northeast Greenland ' , Bulletin of the Geological Society of America , vol. 132 , no. 11-12 , pp. 2282-2294 . https://doi.org/10.1130/b35410.1 |
op_rights |
info:eu-repo/semantics/closedAccess |
op_doi |
https://doi.org/10.1130/b35410.1 |
container_title |
GSA Bulletin |
container_volume |
132 |
container_issue |
11-12 |
container_start_page |
2282 |
op_container_end_page |
2294 |
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1796941407935528960 |