Radar derived Subglacial Properties and Landforms beneath Rutford Ice Stream, West Antarctica
Basal properties beneath ice streams and glaciers are known to be a control for ice flow dynamics, hence knowledge of them is crucial for predicting sea level due to changes in glacial dynamics. Basal properties, processes and topography also drive the formation of subglacial landforms. Bed properti...
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American Geophysical Union (AGU)
2022
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ftleedsuniv:oai:eprints.whiterose.ac.uk:182074 2023-05-15T13:55:51+02:00 Radar derived Subglacial Properties and Landforms beneath Rutford Ice Stream, West Antarctica Schlegel, R Murray, T Smith, AM Brisbourne, AM Booth, AD King, EC Clark, RA 2022-01 text https://eprints.whiterose.ac.uk/182074/ https://eprints.whiterose.ac.uk/182074/3/JGR%20Earth%20Surface%20-%202021%20-%20Schlegel%20-%20Radar%20Derived%20Subglacial%20Properties%20and%20Landforms%20Beneath%20Rutford%20Ice%20Stream%20%20West.pdf en eng American Geophysical Union (AGU) https://eprints.whiterose.ac.uk/182074/3/JGR%20Earth%20Surface%20-%202021%20-%20Schlegel%20-%20Radar%20Derived%20Subglacial%20Properties%20and%20Landforms%20Beneath%20Rutford%20Ice%20Stream%20%20West.pdf Schlegel, R, Murray, T, Smith, AM et al. (4 more authors) (2022) Radar derived Subglacial Properties and Landforms beneath Rutford Ice Stream, West Antarctica. Journal of Geophysical Research: Earth Surface, 127 (1). e2021JF006349. ISSN 2169-9003 cc_by_4 CC-BY Article NonPeerReviewed 2022 ftleedsuniv 2023-01-30T22:43:45Z Basal properties beneath ice streams and glaciers are known to be a control for ice flow dynamics, hence knowledge of them is crucial for predicting sea level due to changes in glacial dynamics. Basal properties, processes and topography also drive the formation of subglacial landforms. Bed properties beneath Rutford Ice Stream (West Antarctica) have previously been described using seismic acoustic impedance measurements at a sparse spatial coverage. Here, we derive bed properties in a 15 × 17 km grid of surface radar data with coverage and sampling much higher than previous seismic studies. Bed reflection amplitudes in surface radar data were calibrated using sediment porosities (ranging from 0.4–0.5) derived from seismic acoustic impedance. We find the bed properties are spatially variable, consisting of low porosity material in some areas and soft sediment in other areas. Comparison of seismic and surface radar data imply the low porosity material to be a consolidated sediment or sedimentary rock. Mega-scale glacial lineations (MSGLs) are ubiquitous on the bed and consist of soft, high porosity, probably deforming sediment, consistent with previous interpretations of MSGLs. We find some MSGLs have high reflectivity on their crest, interpreted as water bodies overlying high porosity sediment, whereas the trough around and the upstream end of some landforms consist of low porosity material. Integrating these different observations, we place constraints on possible explanations for the occurrence of water on the crest of landforms. Article in Journal/Newspaper Antarc* Antarctica Antarctica Journal Rutford Ice Stream West Antarctica White Rose Research Online (Universities of Leeds, Sheffield & York) West Antarctica Rutford ENVELOPE(-85.300,-85.300,-78.600,-78.600) Rutford Ice Stream ENVELOPE(-80.000,-80.000,-79.167,-79.167) |
institution |
Open Polar |
collection |
White Rose Research Online (Universities of Leeds, Sheffield & York) |
op_collection_id |
ftleedsuniv |
language |
English |
description |
Basal properties beneath ice streams and glaciers are known to be a control for ice flow dynamics, hence knowledge of them is crucial for predicting sea level due to changes in glacial dynamics. Basal properties, processes and topography also drive the formation of subglacial landforms. Bed properties beneath Rutford Ice Stream (West Antarctica) have previously been described using seismic acoustic impedance measurements at a sparse spatial coverage. Here, we derive bed properties in a 15 × 17 km grid of surface radar data with coverage and sampling much higher than previous seismic studies. Bed reflection amplitudes in surface radar data were calibrated using sediment porosities (ranging from 0.4–0.5) derived from seismic acoustic impedance. We find the bed properties are spatially variable, consisting of low porosity material in some areas and soft sediment in other areas. Comparison of seismic and surface radar data imply the low porosity material to be a consolidated sediment or sedimentary rock. Mega-scale glacial lineations (MSGLs) are ubiquitous on the bed and consist of soft, high porosity, probably deforming sediment, consistent with previous interpretations of MSGLs. We find some MSGLs have high reflectivity on their crest, interpreted as water bodies overlying high porosity sediment, whereas the trough around and the upstream end of some landforms consist of low porosity material. Integrating these different observations, we place constraints on possible explanations for the occurrence of water on the crest of landforms. |
format |
Article in Journal/Newspaper |
author |
Schlegel, R Murray, T Smith, AM Brisbourne, AM Booth, AD King, EC Clark, RA |
spellingShingle |
Schlegel, R Murray, T Smith, AM Brisbourne, AM Booth, AD King, EC Clark, RA Radar derived Subglacial Properties and Landforms beneath Rutford Ice Stream, West Antarctica |
author_facet |
Schlegel, R Murray, T Smith, AM Brisbourne, AM Booth, AD King, EC Clark, RA |
author_sort |
Schlegel, R |
title |
Radar derived Subglacial Properties and Landforms beneath Rutford Ice Stream, West Antarctica |
title_short |
Radar derived Subglacial Properties and Landforms beneath Rutford Ice Stream, West Antarctica |
title_full |
Radar derived Subglacial Properties and Landforms beneath Rutford Ice Stream, West Antarctica |
title_fullStr |
Radar derived Subglacial Properties and Landforms beneath Rutford Ice Stream, West Antarctica |
title_full_unstemmed |
Radar derived Subglacial Properties and Landforms beneath Rutford Ice Stream, West Antarctica |
title_sort |
radar derived subglacial properties and landforms beneath rutford ice stream, west antarctica |
publisher |
American Geophysical Union (AGU) |
publishDate |
2022 |
url |
https://eprints.whiterose.ac.uk/182074/ https://eprints.whiterose.ac.uk/182074/3/JGR%20Earth%20Surface%20-%202021%20-%20Schlegel%20-%20Radar%20Derived%20Subglacial%20Properties%20and%20Landforms%20Beneath%20Rutford%20Ice%20Stream%20%20West.pdf |
long_lat |
ENVELOPE(-85.300,-85.300,-78.600,-78.600) ENVELOPE(-80.000,-80.000,-79.167,-79.167) |
geographic |
West Antarctica Rutford Rutford Ice Stream |
geographic_facet |
West Antarctica Rutford Rutford Ice Stream |
genre |
Antarc* Antarctica Antarctica Journal Rutford Ice Stream West Antarctica |
genre_facet |
Antarc* Antarctica Antarctica Journal Rutford Ice Stream West Antarctica |
op_relation |
https://eprints.whiterose.ac.uk/182074/3/JGR%20Earth%20Surface%20-%202021%20-%20Schlegel%20-%20Radar%20Derived%20Subglacial%20Properties%20and%20Landforms%20Beneath%20Rutford%20Ice%20Stream%20%20West.pdf Schlegel, R, Murray, T, Smith, AM et al. (4 more authors) (2022) Radar derived Subglacial Properties and Landforms beneath Rutford Ice Stream, West Antarctica. Journal of Geophysical Research: Earth Surface, 127 (1). e2021JF006349. ISSN 2169-9003 |
op_rights |
cc_by_4 |
op_rightsnorm |
CC-BY |
_version_ |
1766262744538939392 |