Deglacial history of the Pensacola Mountains, Antarctica from glacial geomorphology and cosmogenic nuclide surface exposure dating.
The retreat history of the Antarctic Ice Sheet is important for understanding rapid deglaciation, as well as to constrain numerical ice sheet models and ice loading models required for glacial isostatic adjustment modelling. There is particular debate about the extent of grounded ice in the Weddell...
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Online Access: | http://dro.dur.ac.uk/19859/ http://dro.dur.ac.uk/19859/1/19859.pdf http://dro.dur.ac.uk/19859/2/19859.pdf https://doi.org/10.1016/j.quascirev.2016.09.028 |
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ftunivdurham:oai:dro.dur.ac.uk.OAI2:19859 2023-05-15T13:00:06+02:00 Deglacial history of the Pensacola Mountains, Antarctica from glacial geomorphology and cosmogenic nuclide surface exposure dating. Bentley, Michael J. Hein, A.S. Sugden, D.E. Whitehouse, P.L. Shanks, R. Xu, S. Freeman, S.P.H.T. 2017-02-15 application/pdf http://dro.dur.ac.uk/19859/ http://dro.dur.ac.uk/19859/1/19859.pdf http://dro.dur.ac.uk/19859/2/19859.pdf https://doi.org/10.1016/j.quascirev.2016.09.028 unknown Elsevier dro:19859 issn:0277-3791 doi:10.1016/j.quascirev.2016.09.028 http://dro.dur.ac.uk/19859/ https://doi.org/10.1016/j.quascirev.2016.09.028 http://dro.dur.ac.uk/19859/1/19859.pdf http://dro.dur.ac.uk/19859/2/19859.pdf © 2016 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). CC-BY Quaternary science reviews, 2017, Vol.158, pp.58-76 [Peer Reviewed Journal] Article PeerReviewed 2017 ftunivdurham https://doi.org/10.1016/j.quascirev.2016.09.028 2020-05-28T22:35:51Z The retreat history of the Antarctic Ice Sheet is important for understanding rapid deglaciation, as well as to constrain numerical ice sheet models and ice loading models required for glacial isostatic adjustment modelling. There is particular debate about the extent of grounded ice in the Weddell Sea embayment at the Last Glacial Maximum, and its subsequent deglacial history. Here we provide a new dataset of geomorphological observations and cosmogenic nuclide surface exposure ages of erratic samples that constrain the deglacial history of the Pensacola Mountains, adjacent to the present day Foundation Ice Stream and Academy Glacier in the southern Weddell Sea embayment. We show there is evidence of at least two glaciations, the first of which was relatively old and warm-based, and a more recent cold-based glaciation. During the most recent glaciation ice thickened by at least 450 m in the Williams Hills and at least 380 m on Mt Bragg. Progressive thinning from these sites was well underway by 10 ka BP and ice reached present levels by 2.5 ka BP, and is broadly similar to the relatively modest thinning histories in the southern Ellsworth Mountains. The thinning history is consistent with, but does not mandate, a Late Holocene retreat of the grounding line to a smaller-than-present configuration, as has been recently hypothesized based on ice sheet and glacial isostatic modelling. The data also show that clasts with complex exposure histories are pervasive and that clast recycling is highly site-dependent. These new data provide constraints on a reconstruction of the retreat history of the formerly-expanded Foundation Ice Stream, derived using a numerical flowband model. Article in Journal/Newspaper Academy Glacier Antarc* Antarctic Antarctica Foundation Ice Stream Ice Sheet Weddell Sea Durham University: Durham Research Online Academy Glacier ENVELOPE(-60.397,-60.397,-84.250,-84.250) Antarctic Ellsworth Mountains ENVELOPE(-85.000,-85.000,-78.750,-78.750) Foundation Ice Stream ENVELOPE(-60.000,-60.000,-83.250,-83.250) Pensacola Mountains ENVELOPE(-58.000,-58.000,-83.500,-83.500) The Antarctic Weddell Weddell Sea Williams Hills ENVELOPE(-58.916,-58.916,-83.700,-83.700) Quaternary Science Reviews 158 58 76 |
institution |
Open Polar |
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Durham University: Durham Research Online |
op_collection_id |
ftunivdurham |
language |
unknown |
description |
The retreat history of the Antarctic Ice Sheet is important for understanding rapid deglaciation, as well as to constrain numerical ice sheet models and ice loading models required for glacial isostatic adjustment modelling. There is particular debate about the extent of grounded ice in the Weddell Sea embayment at the Last Glacial Maximum, and its subsequent deglacial history. Here we provide a new dataset of geomorphological observations and cosmogenic nuclide surface exposure ages of erratic samples that constrain the deglacial history of the Pensacola Mountains, adjacent to the present day Foundation Ice Stream and Academy Glacier in the southern Weddell Sea embayment. We show there is evidence of at least two glaciations, the first of which was relatively old and warm-based, and a more recent cold-based glaciation. During the most recent glaciation ice thickened by at least 450 m in the Williams Hills and at least 380 m on Mt Bragg. Progressive thinning from these sites was well underway by 10 ka BP and ice reached present levels by 2.5 ka BP, and is broadly similar to the relatively modest thinning histories in the southern Ellsworth Mountains. The thinning history is consistent with, but does not mandate, a Late Holocene retreat of the grounding line to a smaller-than-present configuration, as has been recently hypothesized based on ice sheet and glacial isostatic modelling. The data also show that clasts with complex exposure histories are pervasive and that clast recycling is highly site-dependent. These new data provide constraints on a reconstruction of the retreat history of the formerly-expanded Foundation Ice Stream, derived using a numerical flowband model. |
format |
Article in Journal/Newspaper |
author |
Bentley, Michael J. Hein, A.S. Sugden, D.E. Whitehouse, P.L. Shanks, R. Xu, S. Freeman, S.P.H.T. |
spellingShingle |
Bentley, Michael J. Hein, A.S. Sugden, D.E. Whitehouse, P.L. Shanks, R. Xu, S. Freeman, S.P.H.T. Deglacial history of the Pensacola Mountains, Antarctica from glacial geomorphology and cosmogenic nuclide surface exposure dating. |
author_facet |
Bentley, Michael J. Hein, A.S. Sugden, D.E. Whitehouse, P.L. Shanks, R. Xu, S. Freeman, S.P.H.T. |
author_sort |
Bentley, Michael J. |
title |
Deglacial history of the Pensacola Mountains, Antarctica from glacial geomorphology and cosmogenic nuclide surface exposure dating. |
title_short |
Deglacial history of the Pensacola Mountains, Antarctica from glacial geomorphology and cosmogenic nuclide surface exposure dating. |
title_full |
Deglacial history of the Pensacola Mountains, Antarctica from glacial geomorphology and cosmogenic nuclide surface exposure dating. |
title_fullStr |
Deglacial history of the Pensacola Mountains, Antarctica from glacial geomorphology and cosmogenic nuclide surface exposure dating. |
title_full_unstemmed |
Deglacial history of the Pensacola Mountains, Antarctica from glacial geomorphology and cosmogenic nuclide surface exposure dating. |
title_sort |
deglacial history of the pensacola mountains, antarctica from glacial geomorphology and cosmogenic nuclide surface exposure dating. |
publisher |
Elsevier |
publishDate |
2017 |
url |
http://dro.dur.ac.uk/19859/ http://dro.dur.ac.uk/19859/1/19859.pdf http://dro.dur.ac.uk/19859/2/19859.pdf https://doi.org/10.1016/j.quascirev.2016.09.028 |
long_lat |
ENVELOPE(-60.397,-60.397,-84.250,-84.250) ENVELOPE(-85.000,-85.000,-78.750,-78.750) ENVELOPE(-60.000,-60.000,-83.250,-83.250) ENVELOPE(-58.000,-58.000,-83.500,-83.500) ENVELOPE(-58.916,-58.916,-83.700,-83.700) |
geographic |
Academy Glacier Antarctic Ellsworth Mountains Foundation Ice Stream Pensacola Mountains The Antarctic Weddell Weddell Sea Williams Hills |
geographic_facet |
Academy Glacier Antarctic Ellsworth Mountains Foundation Ice Stream Pensacola Mountains The Antarctic Weddell Weddell Sea Williams Hills |
genre |
Academy Glacier Antarc* Antarctic Antarctica Foundation Ice Stream Ice Sheet Weddell Sea |
genre_facet |
Academy Glacier Antarc* Antarctic Antarctica Foundation Ice Stream Ice Sheet Weddell Sea |
op_source |
Quaternary science reviews, 2017, Vol.158, pp.58-76 [Peer Reviewed Journal] |
op_relation |
dro:19859 issn:0277-3791 doi:10.1016/j.quascirev.2016.09.028 http://dro.dur.ac.uk/19859/ https://doi.org/10.1016/j.quascirev.2016.09.028 http://dro.dur.ac.uk/19859/1/19859.pdf http://dro.dur.ac.uk/19859/2/19859.pdf |
op_rights |
© 2016 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1016/j.quascirev.2016.09.028 |
container_title |
Quaternary Science Reviews |
container_volume |
158 |
container_start_page |
58 |
op_container_end_page |
76 |
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1766188656214671360 |