Seismic and radar observations of subglacial bed forms beneath the onset zone of Rutford Ice Stream, Antarctica
We present seismic and radar data from the onset region of Rutford Ice Stream, West Antarctica, which show the form and internal structure of a variety of bed forms beneath an active ice stream. The ice flow in the area of our survey accelerates from 72 to >200 m a-1, the ice is 2200-3200 m thick...
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International Glaciological Society
2007
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Online Access: | https://nrl.northumbria.ac.uk/id/eprint/20363/ https://doi.org/10.3189/002214307784409216 |
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ftunivnorthumb:oai:nrl.northumbria.ac.uk:20363 2023-05-15T13:35:33+02:00 Seismic and radar observations of subglacial bed forms beneath the onset zone of Rutford Ice Stream, Antarctica King, Edward Woodward, John Smith, Andrew 2007-12 https://nrl.northumbria.ac.uk/id/eprint/20363/ https://doi.org/10.3189/002214307784409216 unknown International Glaciological Society King, Edward, Woodward, John and Smith, Andrew (2007) Seismic and radar observations of subglacial bed forms beneath the onset zone of Rutford Ice Stream, Antarctica. Journal of Glaciology, 53 (183). pp. 665-672. ISSN 0022-1430 F600 Geology F900 Others in Physical Sciences Article PeerReviewed 2007 ftunivnorthumb https://doi.org/10.3189/002214307784409216 2022-09-25T06:00:56Z We present seismic and radar data from the onset region of Rutford Ice Stream, West Antarctica, which show the form and internal structure of a variety of bed forms beneath an active ice stream. The ice flow in the area of our survey accelerates from 72 to >200 m a-1, the ice is 2200-3200 m thick, and the bed of the ice stream lies up to 2000 m below present sea level. We have imaged the internal structure of the bed forms with seismic reflection techniques and also observed radar reflections from below the bed in some circumstances. We observed a transverse moraine 2 km wide and 1.5 km long beneath the slower-flowing part of the ice stream, which we interpret to be composed of unconsolidated sediment undergoing active deformation near the ice-sediment interface. We observed drumlins of classical form with elongation ratios of between 1:1.5 and 1:4.0 where the surface flow speed exceeded 95 m a-1. The conformity of the internal structure of the bed forms with the ice base suggests that the bed forms are active depositional features in congruence with the observation of a contemporary drumlin-forming episode in the distal part of the same ice stream. These observations provide the first direct evidence of the association between ice-stream flow speed and bed-form shape. Article in Journal/Newspaper Antarc* Antarctica Antarctica Journal Journal of Glaciology Rutford Ice Stream West Antarctica Northumbria University, Newcastle: Northumbria Research Link (NRL) Rutford ENVELOPE(-85.300,-85.300,-78.600,-78.600) Rutford Ice Stream ENVELOPE(-80.000,-80.000,-79.167,-79.167) West Antarctica Journal of Glaciology 53 183 665 672 |
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Northumbria University, Newcastle: Northumbria Research Link (NRL) |
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ftunivnorthumb |
language |
unknown |
topic |
F600 Geology F900 Others in Physical Sciences |
spellingShingle |
F600 Geology F900 Others in Physical Sciences King, Edward Woodward, John Smith, Andrew Seismic and radar observations of subglacial bed forms beneath the onset zone of Rutford Ice Stream, Antarctica |
topic_facet |
F600 Geology F900 Others in Physical Sciences |
description |
We present seismic and radar data from the onset region of Rutford Ice Stream, West Antarctica, which show the form and internal structure of a variety of bed forms beneath an active ice stream. The ice flow in the area of our survey accelerates from 72 to >200 m a-1, the ice is 2200-3200 m thick, and the bed of the ice stream lies up to 2000 m below present sea level. We have imaged the internal structure of the bed forms with seismic reflection techniques and also observed radar reflections from below the bed in some circumstances. We observed a transverse moraine 2 km wide and 1.5 km long beneath the slower-flowing part of the ice stream, which we interpret to be composed of unconsolidated sediment undergoing active deformation near the ice-sediment interface. We observed drumlins of classical form with elongation ratios of between 1:1.5 and 1:4.0 where the surface flow speed exceeded 95 m a-1. The conformity of the internal structure of the bed forms with the ice base suggests that the bed forms are active depositional features in congruence with the observation of a contemporary drumlin-forming episode in the distal part of the same ice stream. These observations provide the first direct evidence of the association between ice-stream flow speed and bed-form shape. |
format |
Article in Journal/Newspaper |
author |
King, Edward Woodward, John Smith, Andrew |
author_facet |
King, Edward Woodward, John Smith, Andrew |
author_sort |
King, Edward |
title |
Seismic and radar observations of subglacial bed forms beneath the onset zone of Rutford Ice Stream, Antarctica |
title_short |
Seismic and radar observations of subglacial bed forms beneath the onset zone of Rutford Ice Stream, Antarctica |
title_full |
Seismic and radar observations of subglacial bed forms beneath the onset zone of Rutford Ice Stream, Antarctica |
title_fullStr |
Seismic and radar observations of subglacial bed forms beneath the onset zone of Rutford Ice Stream, Antarctica |
title_full_unstemmed |
Seismic and radar observations of subglacial bed forms beneath the onset zone of Rutford Ice Stream, Antarctica |
title_sort |
seismic and radar observations of subglacial bed forms beneath the onset zone of rutford ice stream, antarctica |
publisher |
International Glaciological Society |
publishDate |
2007 |
url |
https://nrl.northumbria.ac.uk/id/eprint/20363/ https://doi.org/10.3189/002214307784409216 |
long_lat |
ENVELOPE(-85.300,-85.300,-78.600,-78.600) ENVELOPE(-80.000,-80.000,-79.167,-79.167) |
geographic |
Rutford Rutford Ice Stream West Antarctica |
geographic_facet |
Rutford Rutford Ice Stream West Antarctica |
genre |
Antarc* Antarctica Antarctica Journal Journal of Glaciology Rutford Ice Stream West Antarctica |
genre_facet |
Antarc* Antarctica Antarctica Journal Journal of Glaciology Rutford Ice Stream West Antarctica |
op_relation |
King, Edward, Woodward, John and Smith, Andrew (2007) Seismic and radar observations of subglacial bed forms beneath the onset zone of Rutford Ice Stream, Antarctica. Journal of Glaciology, 53 (183). pp. 665-672. ISSN 0022-1430 |
op_doi |
https://doi.org/10.3189/002214307784409216 |
container_title |
Journal of Glaciology |
container_volume |
53 |
container_issue |
183 |
container_start_page |
665 |
op_container_end_page |
672 |
_version_ |
1766067092288700416 |