The timing of fjord formation and early glaciations in North and Northeast Greenland
The timing and extent of early glaciations in Greenland and their co-evolution with the underlying landscape remain elusive. Here we use the concept of geophysical relief to estimate fjord erosion and the subsequent flexural isostatic response to erosional unloading in Northeast and North Greenland...
Published in: | Geology |
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Language: | English |
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Online Access: | https://pure.au.dk/portal/da/publications/the-timing-of-fjord-formation-and-early-glaciations-in-north-and-northeast-greenland(1d8e2df8-620f-49a8-885b-04601d2fdace).html https://doi.org/10.1130/G46064.1 https://pure.au.dk/ws/files/193931285/682.pdf http://www.scopus.com/inward/record.url?scp=85068076958&partnerID=8YFLogxK |
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ftuniaarhuspubl:oai:pure.atira.dk:publications/1d8e2df8-620f-49a8-885b-04601d2fdace 2023-12-31T10:06:22+01:00 The timing of fjord formation and early glaciations in North and Northeast Greenland Pedersen, Vivi K. Larsen, Nicolaj K. Egholm, David L. 2019-07 application/pdf https://pure.au.dk/portal/da/publications/the-timing-of-fjord-formation-and-early-glaciations-in-north-and-northeast-greenland(1d8e2df8-620f-49a8-885b-04601d2fdace).html https://doi.org/10.1130/G46064.1 https://pure.au.dk/ws/files/193931285/682.pdf http://www.scopus.com/inward/record.url?scp=85068076958&partnerID=8YFLogxK eng eng https://pure.au.dk/portal/da/publications/the-timing-of-fjord-formation-and-early-glaciations-in-north-and-northeast-greenland(1d8e2df8-620f-49a8-885b-04601d2fdace).html info:eu-repo/semantics/openAccess Pedersen , V K , Larsen , N K & Egholm , D L 2019 , ' The timing of fjord formation and early glaciations in North and Northeast Greenland ' , Geology , vol. 47 , no. 7 , pp. 682-686 . https://doi.org/10.1130/G46064.1 ATLANTIC CENTRAL-EAST GREENLAND EOCENE EROSION EVOLUTION ICE-SHEET KAP KOBENHAVN FORMATION LANDSCAPE LATE PLIOCENE SEDIMENTS article 2019 ftuniaarhuspubl https://doi.org/10.1130/G46064.1 2023-12-07T00:03:33Z The timing and extent of early glaciations in Greenland and their co-evolution with the underlying landscape remain elusive. Here we use the concept of geophysical relief to estimate fjord erosion and the subsequent flexural isostatic response to erosional unloading in Northeast and North Greenland between Scoresby Sund (70°N) and Independence Fjord (82°N). The timing of erosion and isostatic uplift is constrained by marine sediments of late Pliocene-early Pleistocene age that are now exposed on land between ~24 m and 230 m above sea level. By determining the timing of fjord formation, we can establish the early history of the Greenland Ice Sheet. We find that the Independence Fjord system must have formed by glacial erosion at average rates of ~0.5-1 mm/yr since ca. 2.5 Ma in order to explain the current elevation of the marine Kap København Formation by erosion-induced isostatic uplift. In contrast, fjord formation in the outer parts of Scoresby Sund commenced before the Pleistocene, most likely in late Miocene, and continued throughout the Pleistocene by progressive inland fjord formation. Our results demonstrate that the inception of the Greenland Ice Sheet began in the central parts of Northeast Greenland before the Pleistocene and spread to North Greenland only at the onset of the Pleistocene. Article in Journal/Newspaper East Greenland Greenland Ice Sheet Independence fjord Kap København North Greenland Scoresby Sund Aarhus University: Research Geology 47 7 682 686 |
institution |
Open Polar |
collection |
Aarhus University: Research |
op_collection_id |
ftuniaarhuspubl |
language |
English |
topic |
ATLANTIC CENTRAL-EAST GREENLAND EOCENE EROSION EVOLUTION ICE-SHEET KAP KOBENHAVN FORMATION LANDSCAPE LATE PLIOCENE SEDIMENTS |
spellingShingle |
ATLANTIC CENTRAL-EAST GREENLAND EOCENE EROSION EVOLUTION ICE-SHEET KAP KOBENHAVN FORMATION LANDSCAPE LATE PLIOCENE SEDIMENTS Pedersen, Vivi K. Larsen, Nicolaj K. Egholm, David L. The timing of fjord formation and early glaciations in North and Northeast Greenland |
topic_facet |
ATLANTIC CENTRAL-EAST GREENLAND EOCENE EROSION EVOLUTION ICE-SHEET KAP KOBENHAVN FORMATION LANDSCAPE LATE PLIOCENE SEDIMENTS |
description |
The timing and extent of early glaciations in Greenland and their co-evolution with the underlying landscape remain elusive. Here we use the concept of geophysical relief to estimate fjord erosion and the subsequent flexural isostatic response to erosional unloading in Northeast and North Greenland between Scoresby Sund (70°N) and Independence Fjord (82°N). The timing of erosion and isostatic uplift is constrained by marine sediments of late Pliocene-early Pleistocene age that are now exposed on land between ~24 m and 230 m above sea level. By determining the timing of fjord formation, we can establish the early history of the Greenland Ice Sheet. We find that the Independence Fjord system must have formed by glacial erosion at average rates of ~0.5-1 mm/yr since ca. 2.5 Ma in order to explain the current elevation of the marine Kap København Formation by erosion-induced isostatic uplift. In contrast, fjord formation in the outer parts of Scoresby Sund commenced before the Pleistocene, most likely in late Miocene, and continued throughout the Pleistocene by progressive inland fjord formation. Our results demonstrate that the inception of the Greenland Ice Sheet began in the central parts of Northeast Greenland before the Pleistocene and spread to North Greenland only at the onset of the Pleistocene. |
format |
Article in Journal/Newspaper |
author |
Pedersen, Vivi K. Larsen, Nicolaj K. Egholm, David L. |
author_facet |
Pedersen, Vivi K. Larsen, Nicolaj K. Egholm, David L. |
author_sort |
Pedersen, Vivi K. |
title |
The timing of fjord formation and early glaciations in North and Northeast Greenland |
title_short |
The timing of fjord formation and early glaciations in North and Northeast Greenland |
title_full |
The timing of fjord formation and early glaciations in North and Northeast Greenland |
title_fullStr |
The timing of fjord formation and early glaciations in North and Northeast Greenland |
title_full_unstemmed |
The timing of fjord formation and early glaciations in North and Northeast Greenland |
title_sort |
timing of fjord formation and early glaciations in north and northeast greenland |
publishDate |
2019 |
url |
https://pure.au.dk/portal/da/publications/the-timing-of-fjord-formation-and-early-glaciations-in-north-and-northeast-greenland(1d8e2df8-620f-49a8-885b-04601d2fdace).html https://doi.org/10.1130/G46064.1 https://pure.au.dk/ws/files/193931285/682.pdf http://www.scopus.com/inward/record.url?scp=85068076958&partnerID=8YFLogxK |
genre |
East Greenland Greenland Ice Sheet Independence fjord Kap København North Greenland Scoresby Sund |
genre_facet |
East Greenland Greenland Ice Sheet Independence fjord Kap København North Greenland Scoresby Sund |
op_source |
Pedersen , V K , Larsen , N K & Egholm , D L 2019 , ' The timing of fjord formation and early glaciations in North and Northeast Greenland ' , Geology , vol. 47 , no. 7 , pp. 682-686 . https://doi.org/10.1130/G46064.1 |
op_relation |
https://pure.au.dk/portal/da/publications/the-timing-of-fjord-formation-and-early-glaciations-in-north-and-northeast-greenland(1d8e2df8-620f-49a8-885b-04601d2fdace).html |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1130/G46064.1 |
container_title |
Geology |
container_volume |
47 |
container_issue |
7 |
container_start_page |
682 |
op_container_end_page |
686 |
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1786838374268534784 |