Subglacial geology and geomorphology of the Pensacola‐Pole Basin, East Antarctica
The East Antarctic Ice Sheet (EAIS) is underlain by a series of low‐lying subglacial sedimentary basins. The extent, geology and basal topography of these sedimentary basins are important boundary conditions governing the dynamics of the overlying ice sheet. This is particularly pertinent for basins...
Published in: | Geochemistry, Geophysics, Geosystems |
---|---|
Main Authors: | , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
American Geophysical Union
2019
|
Subjects: | |
Online Access: | http://nora.nerc.ac.uk/id/eprint/523677/ https://nora.nerc.ac.uk/id/eprint/523677/1/2018GC008126.pdf https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018GC008126 |
id |
ftnerc:oai:nora.nerc.ac.uk:523677 |
---|---|
record_format |
openpolar |
spelling |
ftnerc:oai:nora.nerc.ac.uk:523677 2023-05-15T13:41:43+02:00 Subglacial geology and geomorphology of the Pensacola‐Pole Basin, East Antarctica Paxman, Guy J.G. Jamieson, Stewart S.R. Ferraccioli, Fausto Jordan, Tom A. Bentley, Michael J. Ross, Neil Forsberg, René Matsuoka, Kenichi Steinhage, Daniel Eagles, Graeme Casal, Tania G. 2019-07-16 text http://nora.nerc.ac.uk/id/eprint/523677/ https://nora.nerc.ac.uk/id/eprint/523677/1/2018GC008126.pdf https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018GC008126 en eng American Geophysical Union https://nora.nerc.ac.uk/id/eprint/523677/1/2018GC008126.pdf Paxman, Guy J.G.; Jamieson, Stewart S.R.; Ferraccioli, Fausto orcid:0000-0002-9347-4736 Jordan, Tom A. orcid:0000-0003-2780-1986 Bentley, Michael J.; Ross, Neil; Forsberg, René; Matsuoka, Kenichi; Steinhage, Daniel; Eagles, Graeme; Casal, Tania G. 2019 Subglacial geology and geomorphology of the Pensacola‐Pole Basin, East Antarctica. Geochemistry, Geophysics, Geosystems, 20 (6). 2786-2807. https://doi.org/10.1029/2018GC008126 <https://doi.org/10.1029/2018GC008126> cc_by_4 CC-BY Earth Sciences Publication - Article PeerReviewed 2019 ftnerc https://doi.org/10.1029/2018GC008126 2023-02-04T19:48:32Z The East Antarctic Ice Sheet (EAIS) is underlain by a series of low‐lying subglacial sedimentary basins. The extent, geology and basal topography of these sedimentary basins are important boundary conditions governing the dynamics of the overlying ice sheet. This is particularly pertinent for basins close to the grounding line wherein the EAIS is grounded below sea level, and therefore potentially vulnerable to rapid retreat. Here, we analyze newly acquired airborne geophysical data over the Pensacola‐Pole Basin (PPB), a previously unexplored sector of the EAIS. Using a combination of gravity, magnetic and ice‐penetrating radar data, we present the first detailed subglacial sedimentary basin model for the PPB. Radar data reveal that the PPB is defined by a topographic depression situated ~500 m below sea level. Gravity and magnetic depth‐to‐source modeling indicate that the southern part of the basin is underlain by a sedimentary succession 2–3 km thick. This is interpreted as an equivalent of the Beacon Supergroup and associated Ferrar dolerites that are exposed along the margin of East Antarctica. However, we find that similar rocks appear to be largely absent from the northern part of the basin, close to the present‐day grounding line. In addition, the eastern margin of the basin is characterized by a major geological boundary and a system of overdeepened subglacial troughs. We suggest that these characteristics of the basin may reflect the behavior of past ice sheets and/or exert an influence on the present‐day dynamics of the overlying EAIS. Article in Journal/Newspaper Antarc* Antarctic Antarctica East Antarctica Ice Sheet Natural Environment Research Council: NERC Open Research Archive Antarctic East Antarctica East Antarctic Ice Sheet Geochemistry, Geophysics, Geosystems 20 6 2786 2807 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
topic |
Earth Sciences |
spellingShingle |
Earth Sciences Paxman, Guy J.G. Jamieson, Stewart S.R. Ferraccioli, Fausto Jordan, Tom A. Bentley, Michael J. Ross, Neil Forsberg, René Matsuoka, Kenichi Steinhage, Daniel Eagles, Graeme Casal, Tania G. Subglacial geology and geomorphology of the Pensacola‐Pole Basin, East Antarctica |
topic_facet |
Earth Sciences |
description |
The East Antarctic Ice Sheet (EAIS) is underlain by a series of low‐lying subglacial sedimentary basins. The extent, geology and basal topography of these sedimentary basins are important boundary conditions governing the dynamics of the overlying ice sheet. This is particularly pertinent for basins close to the grounding line wherein the EAIS is grounded below sea level, and therefore potentially vulnerable to rapid retreat. Here, we analyze newly acquired airborne geophysical data over the Pensacola‐Pole Basin (PPB), a previously unexplored sector of the EAIS. Using a combination of gravity, magnetic and ice‐penetrating radar data, we present the first detailed subglacial sedimentary basin model for the PPB. Radar data reveal that the PPB is defined by a topographic depression situated ~500 m below sea level. Gravity and magnetic depth‐to‐source modeling indicate that the southern part of the basin is underlain by a sedimentary succession 2–3 km thick. This is interpreted as an equivalent of the Beacon Supergroup and associated Ferrar dolerites that are exposed along the margin of East Antarctica. However, we find that similar rocks appear to be largely absent from the northern part of the basin, close to the present‐day grounding line. In addition, the eastern margin of the basin is characterized by a major geological boundary and a system of overdeepened subglacial troughs. We suggest that these characteristics of the basin may reflect the behavior of past ice sheets and/or exert an influence on the present‐day dynamics of the overlying EAIS. |
format |
Article in Journal/Newspaper |
author |
Paxman, Guy J.G. Jamieson, Stewart S.R. Ferraccioli, Fausto Jordan, Tom A. Bentley, Michael J. Ross, Neil Forsberg, René Matsuoka, Kenichi Steinhage, Daniel Eagles, Graeme Casal, Tania G. |
author_facet |
Paxman, Guy J.G. Jamieson, Stewart S.R. Ferraccioli, Fausto Jordan, Tom A. Bentley, Michael J. Ross, Neil Forsberg, René Matsuoka, Kenichi Steinhage, Daniel Eagles, Graeme Casal, Tania G. |
author_sort |
Paxman, Guy J.G. |
title |
Subglacial geology and geomorphology of the Pensacola‐Pole Basin, East Antarctica |
title_short |
Subglacial geology and geomorphology of the Pensacola‐Pole Basin, East Antarctica |
title_full |
Subglacial geology and geomorphology of the Pensacola‐Pole Basin, East Antarctica |
title_fullStr |
Subglacial geology and geomorphology of the Pensacola‐Pole Basin, East Antarctica |
title_full_unstemmed |
Subglacial geology and geomorphology of the Pensacola‐Pole Basin, East Antarctica |
title_sort |
subglacial geology and geomorphology of the pensacola‐pole basin, east antarctica |
publisher |
American Geophysical Union |
publishDate |
2019 |
url |
http://nora.nerc.ac.uk/id/eprint/523677/ https://nora.nerc.ac.uk/id/eprint/523677/1/2018GC008126.pdf https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018GC008126 |
geographic |
Antarctic East Antarctica East Antarctic Ice Sheet |
geographic_facet |
Antarctic East Antarctica East Antarctic Ice Sheet |
genre |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet |
op_relation |
https://nora.nerc.ac.uk/id/eprint/523677/1/2018GC008126.pdf Paxman, Guy J.G.; Jamieson, Stewart S.R.; Ferraccioli, Fausto orcid:0000-0002-9347-4736 Jordan, Tom A. orcid:0000-0003-2780-1986 Bentley, Michael J.; Ross, Neil; Forsberg, René; Matsuoka, Kenichi; Steinhage, Daniel; Eagles, Graeme; Casal, Tania G. 2019 Subglacial geology and geomorphology of the Pensacola‐Pole Basin, East Antarctica. Geochemistry, Geophysics, Geosystems, 20 (6). 2786-2807. https://doi.org/10.1029/2018GC008126 <https://doi.org/10.1029/2018GC008126> |
op_rights |
cc_by_4 |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1029/2018GC008126 |
container_title |
Geochemistry, Geophysics, Geosystems |
container_volume |
20 |
container_issue |
6 |
container_start_page |
2786 |
op_container_end_page |
2807 |
_version_ |
1766155135051890688 |