Past Ice Stream and Ice Sheet Changes on the Continental Shelf off the Sabrina Coast, East Antarctica
Our understanding of the response of the Antarctic ice sheet to climate and ocean changes requires the improvement of current ice-atmosphere-ocean models and the accurate determination of boundary conditions such as ice thickness and extent at key time intervals, so that satellite gravity observatio...
Published in: | Geomorphology |
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Language: | unknown |
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Digital Commons @ University of South Florida
2018
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Online Access: | https://digitalcommons.usf.edu/msc_facpub/601 https://doi.org/10.1016/j.geomorph.2018.05.020 |
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ftusouthflorida:oai:digitalcommons.usf.edu:msc_facpub-1557 2023-07-30T03:58:47+02:00 Past Ice Stream and Ice Sheet Changes on the Continental Shelf off the Sabrina Coast, East Antarctica Fernandez, R. Gulick, S. Domack, Eugene W. Montelli, A. Leventer, A. Shevenell, Amelia E Frederick, B. The NBP1402 Science Party 2018-09-01T07:00:00Z https://digitalcommons.usf.edu/msc_facpub/601 https://doi.org/10.1016/j.geomorph.2018.05.020 unknown Digital Commons @ University of South Florida https://digitalcommons.usf.edu/msc_facpub/601 doi:10.1016/j.geomorph.2018.05.020 https://doi.org/10.1016/j.geomorph.2018.05.020 Marine Science Faculty Publications East Antarctic Ice Sheet Glacial geomorphology Mega scale glacial lineations Grounding zone wedges Life Sciences article 2018 ftusouthflorida https://doi.org/10.1016/j.geomorph.2018.05.020 2023-07-13T20:45:14Z Our understanding of the response of the Antarctic ice sheet to climate and ocean changes requires the improvement of current ice-atmosphere-ocean models and the accurate determination of boundary conditions such as ice thickness and extent at key time intervals, so that satellite gravity observations and isostatic models can be adjusted. However, large portions of the Antarctic margin remain understudied or lack suitable data. One key area where data are lacking, is the Sabrina Coast portion of the East Antarctic Ice Sheet (EAIS) margin where the Totten Glacier, which has the largest ice discharge in East Antarctica, is accelerating, thinning and loosing mass at high rates. In this work, we present the results of the first geological and geophysical marine survey to the continental shelf offshore of the Dalton Ice Tongue and Moscow University ice shelf, east of the Totten Glacier. The data presented include multibeam swath bathymetry and multichannel seismic, focusing on the sea floor morphology and sedimentary section above a regional angular unconformity separating pre- and post-Miocene glacial strata. Sea floor scouring and iceberg keel marks on the outer shelf, associated with gullies on the upper slope indicate that ice expanded in the past and grounded ~5 km from the shelf edge at ~450–500 mbsl, extending ~155 km north of the current Moscow University Ice Shelf. A nearly 1000 m deep area in the inner-middle shelf, oriented NW with paleo-ice flow direction indicated by mega scale glacial lineations (MSGL) and drumlins, is interpreted as a cross shelf glacial trough. A series of geomorphic associations on the north-eastern side of the glacial trough includes glacial lobes, grounding zone wedges (GZW), glacial lineations and transverse ridges, which indicates slower ice, grounding line stabilization and collapse. These geomorphic associations are organized in 4 four sets representing different past ice-flow configurations reflecting changes in ice flow direction, grounding line position, location of fast and ... Article in Journal/Newspaper Antarc* Antarctic Antarctica East Antarctica Ice Sheet Ice Shelf Iceberg* Moscow University Ice Shelf Totten Glacier University of South Florida St. Petersburg: Digital USFSP Antarctic East Antarctic Ice Sheet East Antarctica Moscow University Ice Shelf ENVELOPE(121.000,121.000,-67.000,-67.000) Sabrina Coast ENVELOPE(118.550,118.550,-67.000,-67.000) The Antarctic Totten Glacier ENVELOPE(116.333,116.333,-66.833,-66.833) Geomorphology 317 10 22 |
institution |
Open Polar |
collection |
University of South Florida St. Petersburg: Digital USFSP |
op_collection_id |
ftusouthflorida |
language |
unknown |
topic |
East Antarctic Ice Sheet Glacial geomorphology Mega scale glacial lineations Grounding zone wedges Life Sciences |
spellingShingle |
East Antarctic Ice Sheet Glacial geomorphology Mega scale glacial lineations Grounding zone wedges Life Sciences Fernandez, R. Gulick, S. Domack, Eugene W. Montelli, A. Leventer, A. Shevenell, Amelia E Frederick, B. The NBP1402 Science Party Past Ice Stream and Ice Sheet Changes on the Continental Shelf off the Sabrina Coast, East Antarctica |
topic_facet |
East Antarctic Ice Sheet Glacial geomorphology Mega scale glacial lineations Grounding zone wedges Life Sciences |
description |
Our understanding of the response of the Antarctic ice sheet to climate and ocean changes requires the improvement of current ice-atmosphere-ocean models and the accurate determination of boundary conditions such as ice thickness and extent at key time intervals, so that satellite gravity observations and isostatic models can be adjusted. However, large portions of the Antarctic margin remain understudied or lack suitable data. One key area where data are lacking, is the Sabrina Coast portion of the East Antarctic Ice Sheet (EAIS) margin where the Totten Glacier, which has the largest ice discharge in East Antarctica, is accelerating, thinning and loosing mass at high rates. In this work, we present the results of the first geological and geophysical marine survey to the continental shelf offshore of the Dalton Ice Tongue and Moscow University ice shelf, east of the Totten Glacier. The data presented include multibeam swath bathymetry and multichannel seismic, focusing on the sea floor morphology and sedimentary section above a regional angular unconformity separating pre- and post-Miocene glacial strata. Sea floor scouring and iceberg keel marks on the outer shelf, associated with gullies on the upper slope indicate that ice expanded in the past and grounded ~5 km from the shelf edge at ~450–500 mbsl, extending ~155 km north of the current Moscow University Ice Shelf. A nearly 1000 m deep area in the inner-middle shelf, oriented NW with paleo-ice flow direction indicated by mega scale glacial lineations (MSGL) and drumlins, is interpreted as a cross shelf glacial trough. A series of geomorphic associations on the north-eastern side of the glacial trough includes glacial lobes, grounding zone wedges (GZW), glacial lineations and transverse ridges, which indicates slower ice, grounding line stabilization and collapse. These geomorphic associations are organized in 4 four sets representing different past ice-flow configurations reflecting changes in ice flow direction, grounding line position, location of fast and ... |
format |
Article in Journal/Newspaper |
author |
Fernandez, R. Gulick, S. Domack, Eugene W. Montelli, A. Leventer, A. Shevenell, Amelia E Frederick, B. The NBP1402 Science Party |
author_facet |
Fernandez, R. Gulick, S. Domack, Eugene W. Montelli, A. Leventer, A. Shevenell, Amelia E Frederick, B. The NBP1402 Science Party |
author_sort |
Fernandez, R. |
title |
Past Ice Stream and Ice Sheet Changes on the Continental Shelf off the Sabrina Coast, East Antarctica |
title_short |
Past Ice Stream and Ice Sheet Changes on the Continental Shelf off the Sabrina Coast, East Antarctica |
title_full |
Past Ice Stream and Ice Sheet Changes on the Continental Shelf off the Sabrina Coast, East Antarctica |
title_fullStr |
Past Ice Stream and Ice Sheet Changes on the Continental Shelf off the Sabrina Coast, East Antarctica |
title_full_unstemmed |
Past Ice Stream and Ice Sheet Changes on the Continental Shelf off the Sabrina Coast, East Antarctica |
title_sort |
past ice stream and ice sheet changes on the continental shelf off the sabrina coast, east antarctica |
publisher |
Digital Commons @ University of South Florida |
publishDate |
2018 |
url |
https://digitalcommons.usf.edu/msc_facpub/601 https://doi.org/10.1016/j.geomorph.2018.05.020 |
long_lat |
ENVELOPE(121.000,121.000,-67.000,-67.000) ENVELOPE(118.550,118.550,-67.000,-67.000) ENVELOPE(116.333,116.333,-66.833,-66.833) |
geographic |
Antarctic East Antarctic Ice Sheet East Antarctica Moscow University Ice Shelf Sabrina Coast The Antarctic Totten Glacier |
geographic_facet |
Antarctic East Antarctic Ice Sheet East Antarctica Moscow University Ice Shelf Sabrina Coast The Antarctic Totten Glacier |
genre |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet Ice Shelf Iceberg* Moscow University Ice Shelf Totten Glacier |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet Ice Shelf Iceberg* Moscow University Ice Shelf Totten Glacier |
op_source |
Marine Science Faculty Publications |
op_relation |
https://digitalcommons.usf.edu/msc_facpub/601 doi:10.1016/j.geomorph.2018.05.020 https://doi.org/10.1016/j.geomorph.2018.05.020 |
op_doi |
https://doi.org/10.1016/j.geomorph.2018.05.020 |
container_title |
Geomorphology |
container_volume |
317 |
container_start_page |
10 |
op_container_end_page |
22 |
_version_ |
1772809516361973760 |