Last glacial ice sheet dynamics offshore NE Greenland – a case study from Store Koldewey Trough
The presence of a grounded Greenland Ice Sheet on the northeastern part of the Greenland continental shelf during the Last Glacial Maximum is supported by new swath bathymetry and high-resolution seismic data, supplemented with multi-proxy analyses of sediment gravity cores from Store Koldewey Troug...
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ftdoajarticles:oai:doaj.org/article:9eaccadedaeb4991a8f4b45429f461e5 2023-05-15T16:19:43+02:00 Last glacial ice sheet dynamics offshore NE Greenland – a case study from Store Koldewey Trough I. L. Olsen T. A. Rydningen M. Forwick J. S. Laberg K. Husum 2020-12-01T00:00:00Z https://doi.org/10.5194/tc-14-4475-2020 https://doaj.org/article/9eaccadedaeb4991a8f4b45429f461e5 EN eng Copernicus Publications https://tc.copernicus.org/articles/14/4475/2020/tc-14-4475-2020.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-14-4475-2020 1994-0416 1994-0424 https://doaj.org/article/9eaccadedaeb4991a8f4b45429f461e5 The Cryosphere, Vol 14, Pp 4475-4494 (2020) Environmental sciences GE1-350 Geology QE1-996.5 article 2020 ftdoajarticles https://doi.org/10.5194/tc-14-4475-2020 2022-12-31T05:29:31Z The presence of a grounded Greenland Ice Sheet on the northeastern part of the Greenland continental shelf during the Last Glacial Maximum is supported by new swath bathymetry and high-resolution seismic data, supplemented with multi-proxy analyses of sediment gravity cores from Store Koldewey Trough. Subglacial till fills the trough, with an overlying drape of maximum 2.5 m thick glacier-proximal and glacier-distal sediment. The presence of mega-scale glacial lineations and a grounding zone wedge in the outer part of the trough, comprising subglacial till, provides evidence of the expansion of fast-flowing, grounded ice, probably originating from the area presently covered with the Storstrømmen ice stream and thereby previously flowing across Store Koldewey Island and Germania Land. Grounding zone wedges and recessional moraines provide evidence that multiple halts and/or readvances interrupted the deglaciation. The formation of the grounding zone wedges is estimated to be at least 130 years, while distances between the recessional moraines indicate that the grounding line locally retreated between 80 and 400 m yr −1 during the deglaciation, assuming that the moraines formed annually. The complex geomorphology in Store Koldewey Trough is attributed to the trough shallowing and narrowing towards the coast. At a late stage of the deglaciation, the ice stream flowed around the topography on Store Koldewey Island and Germania Land, terminating the sediment input from this sector of the Greenland Ice Sheet to Store Koldewey Trough. Article in Journal/Newspaper Germania land glacier Greenland Ice Sheet Koldewey island Store koldewey The Cryosphere Directory of Open Access Journals: DOAJ Articles Germania Land ENVELOPE(-20.042,-20.042,77.129,77.129) Greenland Store Koldewey ENVELOPE(-18.820,-18.820,76.364,76.364) The Cryosphere 14 12 4475 4494 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 I. L. Olsen T. A. Rydningen M. Forwick J. S. Laberg K. Husum Last glacial ice sheet dynamics offshore NE Greenland – a case study from Store Koldewey Trough |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
The presence of a grounded Greenland Ice Sheet on the northeastern part of the Greenland continental shelf during the Last Glacial Maximum is supported by new swath bathymetry and high-resolution seismic data, supplemented with multi-proxy analyses of sediment gravity cores from Store Koldewey Trough. Subglacial till fills the trough, with an overlying drape of maximum 2.5 m thick glacier-proximal and glacier-distal sediment. The presence of mega-scale glacial lineations and a grounding zone wedge in the outer part of the trough, comprising subglacial till, provides evidence of the expansion of fast-flowing, grounded ice, probably originating from the area presently covered with the Storstrømmen ice stream and thereby previously flowing across Store Koldewey Island and Germania Land. Grounding zone wedges and recessional moraines provide evidence that multiple halts and/or readvances interrupted the deglaciation. The formation of the grounding zone wedges is estimated to be at least 130 years, while distances between the recessional moraines indicate that the grounding line locally retreated between 80 and 400 m yr −1 during the deglaciation, assuming that the moraines formed annually. The complex geomorphology in Store Koldewey Trough is attributed to the trough shallowing and narrowing towards the coast. At a late stage of the deglaciation, the ice stream flowed around the topography on Store Koldewey Island and Germania Land, terminating the sediment input from this sector of the Greenland Ice Sheet to Store Koldewey Trough. |
format |
Article in Journal/Newspaper |
author |
I. L. Olsen T. A. Rydningen M. Forwick J. S. Laberg K. Husum |
author_facet |
I. L. Olsen T. A. Rydningen M. Forwick J. S. Laberg K. Husum |
author_sort |
I. L. Olsen |
title |
Last glacial ice sheet dynamics offshore NE Greenland – a case study from Store Koldewey Trough |
title_short |
Last glacial ice sheet dynamics offshore NE Greenland – a case study from Store Koldewey Trough |
title_full |
Last glacial ice sheet dynamics offshore NE Greenland – a case study from Store Koldewey Trough |
title_fullStr |
Last glacial ice sheet dynamics offshore NE Greenland – a case study from Store Koldewey Trough |
title_full_unstemmed |
Last glacial ice sheet dynamics offshore NE Greenland – a case study from Store Koldewey Trough |
title_sort |
last glacial ice sheet dynamics offshore ne greenland – a case study from store koldewey trough |
publisher |
Copernicus Publications |
publishDate |
2020 |
url |
https://doi.org/10.5194/tc-14-4475-2020 https://doaj.org/article/9eaccadedaeb4991a8f4b45429f461e5 |
long_lat |
ENVELOPE(-20.042,-20.042,77.129,77.129) ENVELOPE(-18.820,-18.820,76.364,76.364) |
geographic |
Germania Land Greenland Store Koldewey |
geographic_facet |
Germania Land Greenland Store Koldewey |
genre |
Germania land glacier Greenland Ice Sheet Koldewey island Store koldewey The Cryosphere |
genre_facet |
Germania land glacier Greenland Ice Sheet Koldewey island Store koldewey The Cryosphere |
op_source |
The Cryosphere, Vol 14, Pp 4475-4494 (2020) |
op_relation |
https://tc.copernicus.org/articles/14/4475/2020/tc-14-4475-2020.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-14-4475-2020 1994-0416 1994-0424 https://doaj.org/article/9eaccadedaeb4991a8f4b45429f461e5 |
op_doi |
https://doi.org/10.5194/tc-14-4475-2020 |
container_title |
The Cryosphere |
container_volume |
14 |
container_issue |
12 |
container_start_page |
4475 |
op_container_end_page |
4494 |
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1766006122599153664 |