Glacimarine sediments from outer Drygalski Trough, sub-Antarctic South Georgia – evidence for extensive glaciation during the Last Glacial Maximum
South Georgia, one of the largest sub-Antarctic islands, is located within the Southern Ocean and is influenced by the moisture-supplying Southern Westerlies and the Antarctic Circumpolar Current, which are highly susceptible to Southern Hemisphere climate variability. Its unique location causes Sou...
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ftawi:oai:epic.awi.de:57290 2024-09-15T17:41:35+00:00 Glacimarine sediments from outer Drygalski Trough, sub-Antarctic South Georgia – evidence for extensive glaciation during the Last Glacial Maximum Lešić, Nina-Marie Streuff, Katharina Teresa Bohrmann, Gerhard Kuhn, Gerhard 2022 https://epic.awi.de/id/eprint/57290/ https://doi.org/10.1016/j.quascirev.2022.107657 https://hdl.handle.net/10013/epic.b0af47b1-c41a-45b4-b2c9-b7fcf9a6da9e unknown Lešić, N. M. , Streuff, K. T. , Bohrmann, G. and Kuhn, G. orcid:0000-0001-6069-7485 (2022) Glacimarine sediments from outer Drygalski Trough, sub-Antarctic South Georgia – evidence for extensive glaciation during the Last Glacial Maximum , Quaternary Science Reviews, 292 , p. 107657 . doi:10.1016/j.quascirev.2022.107657 <https://doi.org/10.1016/j.quascirev.2022.107657> , hdl:10013/epic.b0af47b1-c41a-45b4-b2c9-b7fcf9a6da9e EPIC3Quaternary Science Reviews, 292, pp. 107657, ISSN: 02773791 Article isiRev 2022 ftawi https://doi.org/10.1016/j.quascirev.2022.107657 2024-06-24T04:30:12Z South Georgia, one of the largest sub-Antarctic islands, is located within the Southern Ocean and is influenced by the moisture-supplying Southern Westerlies and the Antarctic Circumpolar Current, which are highly susceptible to Southern Hemisphere climate variability. Its unique location causes South Georgia's remaining ice masses to react sensitively to climate change, resulting in highly dynamic ice cap waxing and waning, as well as in geomorphological and sedimentological changes on the island and its continental shelf. Sediments around the island have been archiving this ice cap behaviour since at least the Last Glacial Maximum (LGM) and are therefore an important target to investigate past ice cap evolution and climate. Despite several interdisciplinary studies on land and in coastal areas, much of the glacial history is still poorly constrained due to a lack of offshore data. This study presents the, thus far, most distal marine sediment succession from outer Drygalski Trough on the mid-continental shelf of South Georgia. Composite multi-proxy-analyses, together with radiocarbon dating, sub-bottom profiler and high-resolution bathymetric data provide first insights into the evolution of a large glacial trough south of South Georgia since the LGM. Several moraines close to the shelf edge indicate shelf-wide glaciation during the local LGM, which, based on extrapolation of the oldest reliable radiocarbon date, occurred before 30 ka BP at the earliest. Basal stratified diamicton at the core site was interpreted as waterlain till deposited in a subglacial cavity with restricted seawater access and suggests grounding zone-proximal sedimentation in the early phases of deglaciation. The ice margin remained stable until ∼17.5 cal ka BP, when ice quickly retreated from the mid-continental shelf and sedimentation at the core site was dominated by hemipelagic suspension settling with some iceberg melting. Further retreat was interrupted by a local ice readvance and associated increased hinterland erosion during the ... Article in Journal/Newspaper Antarc* Antarctic Ice cap Iceberg* Southern Ocean Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Quaternary Science Reviews 292 107657 |
institution |
Open Polar |
collection |
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
South Georgia, one of the largest sub-Antarctic islands, is located within the Southern Ocean and is influenced by the moisture-supplying Southern Westerlies and the Antarctic Circumpolar Current, which are highly susceptible to Southern Hemisphere climate variability. Its unique location causes South Georgia's remaining ice masses to react sensitively to climate change, resulting in highly dynamic ice cap waxing and waning, as well as in geomorphological and sedimentological changes on the island and its continental shelf. Sediments around the island have been archiving this ice cap behaviour since at least the Last Glacial Maximum (LGM) and are therefore an important target to investigate past ice cap evolution and climate. Despite several interdisciplinary studies on land and in coastal areas, much of the glacial history is still poorly constrained due to a lack of offshore data. This study presents the, thus far, most distal marine sediment succession from outer Drygalski Trough on the mid-continental shelf of South Georgia. Composite multi-proxy-analyses, together with radiocarbon dating, sub-bottom profiler and high-resolution bathymetric data provide first insights into the evolution of a large glacial trough south of South Georgia since the LGM. Several moraines close to the shelf edge indicate shelf-wide glaciation during the local LGM, which, based on extrapolation of the oldest reliable radiocarbon date, occurred before 30 ka BP at the earliest. Basal stratified diamicton at the core site was interpreted as waterlain till deposited in a subglacial cavity with restricted seawater access and suggests grounding zone-proximal sedimentation in the early phases of deglaciation. The ice margin remained stable until ∼17.5 cal ka BP, when ice quickly retreated from the mid-continental shelf and sedimentation at the core site was dominated by hemipelagic suspension settling with some iceberg melting. Further retreat was interrupted by a local ice readvance and associated increased hinterland erosion during the ... |
format |
Article in Journal/Newspaper |
author |
Lešić, Nina-Marie Streuff, Katharina Teresa Bohrmann, Gerhard Kuhn, Gerhard |
spellingShingle |
Lešić, Nina-Marie Streuff, Katharina Teresa Bohrmann, Gerhard Kuhn, Gerhard Glacimarine sediments from outer Drygalski Trough, sub-Antarctic South Georgia – evidence for extensive glaciation during the Last Glacial Maximum |
author_facet |
Lešić, Nina-Marie Streuff, Katharina Teresa Bohrmann, Gerhard Kuhn, Gerhard |
author_sort |
Lešić, Nina-Marie |
title |
Glacimarine sediments from outer Drygalski Trough, sub-Antarctic South Georgia – evidence for extensive glaciation during the Last Glacial Maximum |
title_short |
Glacimarine sediments from outer Drygalski Trough, sub-Antarctic South Georgia – evidence for extensive glaciation during the Last Glacial Maximum |
title_full |
Glacimarine sediments from outer Drygalski Trough, sub-Antarctic South Georgia – evidence for extensive glaciation during the Last Glacial Maximum |
title_fullStr |
Glacimarine sediments from outer Drygalski Trough, sub-Antarctic South Georgia – evidence for extensive glaciation during the Last Glacial Maximum |
title_full_unstemmed |
Glacimarine sediments from outer Drygalski Trough, sub-Antarctic South Georgia – evidence for extensive glaciation during the Last Glacial Maximum |
title_sort |
glacimarine sediments from outer drygalski trough, sub-antarctic south georgia – evidence for extensive glaciation during the last glacial maximum |
publishDate |
2022 |
url |
https://epic.awi.de/id/eprint/57290/ https://doi.org/10.1016/j.quascirev.2022.107657 https://hdl.handle.net/10013/epic.b0af47b1-c41a-45b4-b2c9-b7fcf9a6da9e |
genre |
Antarc* Antarctic Ice cap Iceberg* Southern Ocean |
genre_facet |
Antarc* Antarctic Ice cap Iceberg* Southern Ocean |
op_source |
EPIC3Quaternary Science Reviews, 292, pp. 107657, ISSN: 02773791 |
op_relation |
Lešić, N. M. , Streuff, K. T. , Bohrmann, G. and Kuhn, G. orcid:0000-0001-6069-7485 (2022) Glacimarine sediments from outer Drygalski Trough, sub-Antarctic South Georgia – evidence for extensive glaciation during the Last Glacial Maximum , Quaternary Science Reviews, 292 , p. 107657 . doi:10.1016/j.quascirev.2022.107657 <https://doi.org/10.1016/j.quascirev.2022.107657> , hdl:10013/epic.b0af47b1-c41a-45b4-b2c9-b7fcf9a6da9e |
op_doi |
https://doi.org/10.1016/j.quascirev.2022.107657 |
container_title |
Quaternary Science Reviews |
container_volume |
292 |
container_start_page |
107657 |
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1810487807287754752 |