A reinterpretation of geomorphological evidence for Glacial Lake Victoria, McMurdo Dry Valleys
The largely snow and ice free McMurdo Dry Valleys of Antarctica are one of the coldest and driest locations on Earth. It has been proposed that during the Last Glacial Maximum (LGM) to the early Holocene large lakes up to 200m deep and 100km in area occupied these valleys. We present the first topog...
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Language: | English |
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Online Access: | https://espace.library.uq.edu.au/view/UQ:323513 |
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ftunivqespace:oai:espace.library.uq.edu.au:UQ:323513 2023-05-15T13:07:35+02:00 A reinterpretation of geomorphological evidence for Glacial Lake Victoria, McMurdo Dry Valleys McGowan, Hamish A. Neil, David T. Speirs, Johanna C. 2014-03-01 https://espace.library.uq.edu.au/view/UQ:323513 eng eng Elsevier doi:10.1016/j.geomorph.2013.12.005 issn:0169-555X issn:1872-695X orcid:0000-0002-2844-2084 Not set AINGRA06121 Victoria Valley Antarctic Shorelines Mass movement LiDAR Glacier 1904 Earth-Surface Processes Journal Article 2014 ftunivqespace https://doi.org/10.1016/j.geomorph.2013.12.005 2020-12-15T01:08:29Z The largely snow and ice free McMurdo Dry Valleys of Antarctica are one of the coldest and driest locations on Earth. It has been proposed that during the Last Glacial Maximum (LGM) to the early Holocene large lakes up to 200m deep and 100km in area occupied these valleys. We present the first topographic survey of features reported to be shorelines from one such lake, Glacial Lake Victoria, in Victoria Valley. In combination with the analysis of laser altimetry data obtained from the NASA Airborne Topographic Mapper system and cosmogenic dating of granite boulders we show that the features previously thought to be shorelines are not horizontally or linearly continuous. Rather, we conclude that they are scars from ancient slope mass movement deposits. Be cosmogenic dating indicates that their formation is on timescales of at least 160ka before present and not 20ka as the LGM mega-lake hypothesis suggests. We conclude that the geomorphic features believed to be shorelines and which underpin the LGM mega-lake hypothesis in Victoria Valley are mass movement deposits and not lake shorelines. Our results support an emerging body of literature unable to find evidence to verify the McMurdo Dry Valleys LGM mega-lake hypothesis. Accordingly we suggest caution in invoking such significant landscape features in discussions of the environmental past of this unique region until such time as further research provides an unequivocal history of the region's geomorphic past. Article in Journal/Newspaper Airborne Topographic Mapper Antarc* Antarctic Antarctica McMurdo Dry Valleys The University of Queensland: UQ eSpace Antarctic Glacial Lake ENVELOPE(-129.463,-129.463,58.259,58.259) McMurdo Dry Valleys Victoria Valley ENVELOPE(162.000,162.000,-77.383,-77.383) Geomorphology 208 200 206 |
institution |
Open Polar |
collection |
The University of Queensland: UQ eSpace |
op_collection_id |
ftunivqespace |
language |
English |
topic |
Victoria Valley Antarctic Shorelines Mass movement LiDAR Glacier 1904 Earth-Surface Processes |
spellingShingle |
Victoria Valley Antarctic Shorelines Mass movement LiDAR Glacier 1904 Earth-Surface Processes McGowan, Hamish A. Neil, David T. Speirs, Johanna C. A reinterpretation of geomorphological evidence for Glacial Lake Victoria, McMurdo Dry Valleys |
topic_facet |
Victoria Valley Antarctic Shorelines Mass movement LiDAR Glacier 1904 Earth-Surface Processes |
description |
The largely snow and ice free McMurdo Dry Valleys of Antarctica are one of the coldest and driest locations on Earth. It has been proposed that during the Last Glacial Maximum (LGM) to the early Holocene large lakes up to 200m deep and 100km in area occupied these valleys. We present the first topographic survey of features reported to be shorelines from one such lake, Glacial Lake Victoria, in Victoria Valley. In combination with the analysis of laser altimetry data obtained from the NASA Airborne Topographic Mapper system and cosmogenic dating of granite boulders we show that the features previously thought to be shorelines are not horizontally or linearly continuous. Rather, we conclude that they are scars from ancient slope mass movement deposits. Be cosmogenic dating indicates that their formation is on timescales of at least 160ka before present and not 20ka as the LGM mega-lake hypothesis suggests. We conclude that the geomorphic features believed to be shorelines and which underpin the LGM mega-lake hypothesis in Victoria Valley are mass movement deposits and not lake shorelines. Our results support an emerging body of literature unable to find evidence to verify the McMurdo Dry Valleys LGM mega-lake hypothesis. Accordingly we suggest caution in invoking such significant landscape features in discussions of the environmental past of this unique region until such time as further research provides an unequivocal history of the region's geomorphic past. |
format |
Article in Journal/Newspaper |
author |
McGowan, Hamish A. Neil, David T. Speirs, Johanna C. |
author_facet |
McGowan, Hamish A. Neil, David T. Speirs, Johanna C. |
author_sort |
McGowan, Hamish A. |
title |
A reinterpretation of geomorphological evidence for Glacial Lake Victoria, McMurdo Dry Valleys |
title_short |
A reinterpretation of geomorphological evidence for Glacial Lake Victoria, McMurdo Dry Valleys |
title_full |
A reinterpretation of geomorphological evidence for Glacial Lake Victoria, McMurdo Dry Valleys |
title_fullStr |
A reinterpretation of geomorphological evidence for Glacial Lake Victoria, McMurdo Dry Valleys |
title_full_unstemmed |
A reinterpretation of geomorphological evidence for Glacial Lake Victoria, McMurdo Dry Valleys |
title_sort |
reinterpretation of geomorphological evidence for glacial lake victoria, mcmurdo dry valleys |
publisher |
Elsevier |
publishDate |
2014 |
url |
https://espace.library.uq.edu.au/view/UQ:323513 |
long_lat |
ENVELOPE(-129.463,-129.463,58.259,58.259) ENVELOPE(162.000,162.000,-77.383,-77.383) |
geographic |
Antarctic Glacial Lake McMurdo Dry Valleys Victoria Valley |
geographic_facet |
Antarctic Glacial Lake McMurdo Dry Valleys Victoria Valley |
genre |
Airborne Topographic Mapper Antarc* Antarctic Antarctica McMurdo Dry Valleys |
genre_facet |
Airborne Topographic Mapper Antarc* Antarctic Antarctica McMurdo Dry Valleys |
op_relation |
doi:10.1016/j.geomorph.2013.12.005 issn:0169-555X issn:1872-695X orcid:0000-0002-2844-2084 Not set AINGRA06121 |
op_doi |
https://doi.org/10.1016/j.geomorph.2013.12.005 |
container_title |
Geomorphology |
container_volume |
208 |
container_start_page |
200 |
op_container_end_page |
206 |
_version_ |
1766060019648823296 |