Marine sediment record from the East Antarctic margin reveals dynamics of ice sheet recession
The Antarctic shelf is traversed by large-scale troughs developed by glacial erosion. Swath bathymetric, lithologic, and chronologic data from jumbo piston cores from four sites along the East Antarctic margin (Iceberg Alley, the Nielsen Basin, the Svenner Channel, and the Mertz-Ninnis Trough) are u...
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ftopenunivgb:oai:oro.open.ac.uk:6006 2024-06-23T07:46:55+00:00 Marine sediment record from the East Antarctic margin reveals dynamics of ice sheet recession Leventer, Amy Domack, Eugene Dunbar, Robert Pike, Jennifer Stickley, Catherine Maddison, Eleanor Brachfeld, Stefanie Manley, Patricia McClennen, Charlie 2006-12 https://oro.open.ac.uk/6006/ http://www.gsajournals.org/perlserv/?request=get-document&doi=10.1130%2FGSAT01612A.1 unknown Leventer, Amy; Domack, Eugene; Dunbar, Robert; Pike, Jennifer; Stickley, Catherine; Maddison, Eleanor <https://oro.open.ac.uk/view/person/ejm367.html>; Brachfeld, Stefanie; Manley, Patricia and McClennen, Charlie (2006). Marine sediment record from the East Antarctic margin reveals dynamics of ice sheet recession. GSA Today, 16(12) pp. 4–10. Journal Item PeerReviewed 2006 ftopenunivgb 2024-06-05T00:37:59Z The Antarctic shelf is traversed by large-scale troughs developed by glacial erosion. Swath bathymetric, lithologic, and chronologic data from jumbo piston cores from four sites along the East Antarctic margin (Iceberg Alley, the Nielsen Basin, the Svenner Channel, and the Mertz-Ninnis Trough) are used to demonstrate that these cross-shelf features controlled development of calving bay reentrants in the Antarctic ice sheet during deglaciation. At all sites except the Mertz-Ninnis Trough, the transition between the Last Glacial Maximum and the Holocene is characterized by varved couplets deposited during a short interval of extremely high primary productivity in a fjordlike setting. Nearly monospecific layers of the diatom Chaetoceros alternate with slightly more terrigenous layers containing a mixed diatom assemblage. We propose that springtime diatom blooms dominated by Chaetoceros were generated within well-stratified and restricted surface waters of calving bays that were influenced by the input of iron-rich meltwater. Intervening post-bloom summer-fall laminae were formed through the downward flux of terrigenous material sourced from melting glacial ice combined with mixed diatom assemblages. Radiocarbon-based chronologies that constrain the timing of deposition of the varved sediments within calving bay reentrants along the East Antarctic margin place deglaciation between ca. 10,500–11,500 cal yr B.P., post-dating Meltwater Pulse 1A (14,200 cal yr B.P.) and indicating that retreat of ice from the East Antarctic margin was not the major contributor to this pulse of meltwater. Article in Journal/Newspaper Antarc* Antarctic Ice Sheet Iceberg* The Open University: Open Research Online (ORO) Antarctic The Antarctic Svenner ENVELOPE(76.833,76.833,-69.083,-69.083) Mertz-Ninnis Trough ENVELOPE(146.000,146.000,-67.417,-67.417) Svenner Channel ENVELOPE(76.342,76.342,-68.858,-68.858) GSA Today 16 12 4 |
institution |
Open Polar |
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The Open University: Open Research Online (ORO) |
op_collection_id |
ftopenunivgb |
language |
unknown |
description |
The Antarctic shelf is traversed by large-scale troughs developed by glacial erosion. Swath bathymetric, lithologic, and chronologic data from jumbo piston cores from four sites along the East Antarctic margin (Iceberg Alley, the Nielsen Basin, the Svenner Channel, and the Mertz-Ninnis Trough) are used to demonstrate that these cross-shelf features controlled development of calving bay reentrants in the Antarctic ice sheet during deglaciation. At all sites except the Mertz-Ninnis Trough, the transition between the Last Glacial Maximum and the Holocene is characterized by varved couplets deposited during a short interval of extremely high primary productivity in a fjordlike setting. Nearly monospecific layers of the diatom Chaetoceros alternate with slightly more terrigenous layers containing a mixed diatom assemblage. We propose that springtime diatom blooms dominated by Chaetoceros were generated within well-stratified and restricted surface waters of calving bays that were influenced by the input of iron-rich meltwater. Intervening post-bloom summer-fall laminae were formed through the downward flux of terrigenous material sourced from melting glacial ice combined with mixed diatom assemblages. Radiocarbon-based chronologies that constrain the timing of deposition of the varved sediments within calving bay reentrants along the East Antarctic margin place deglaciation between ca. 10,500–11,500 cal yr B.P., post-dating Meltwater Pulse 1A (14,200 cal yr B.P.) and indicating that retreat of ice from the East Antarctic margin was not the major contributor to this pulse of meltwater. |
format |
Article in Journal/Newspaper |
author |
Leventer, Amy Domack, Eugene Dunbar, Robert Pike, Jennifer Stickley, Catherine Maddison, Eleanor Brachfeld, Stefanie Manley, Patricia McClennen, Charlie |
spellingShingle |
Leventer, Amy Domack, Eugene Dunbar, Robert Pike, Jennifer Stickley, Catherine Maddison, Eleanor Brachfeld, Stefanie Manley, Patricia McClennen, Charlie Marine sediment record from the East Antarctic margin reveals dynamics of ice sheet recession |
author_facet |
Leventer, Amy Domack, Eugene Dunbar, Robert Pike, Jennifer Stickley, Catherine Maddison, Eleanor Brachfeld, Stefanie Manley, Patricia McClennen, Charlie |
author_sort |
Leventer, Amy |
title |
Marine sediment record from the East Antarctic margin reveals dynamics of ice sheet recession |
title_short |
Marine sediment record from the East Antarctic margin reveals dynamics of ice sheet recession |
title_full |
Marine sediment record from the East Antarctic margin reveals dynamics of ice sheet recession |
title_fullStr |
Marine sediment record from the East Antarctic margin reveals dynamics of ice sheet recession |
title_full_unstemmed |
Marine sediment record from the East Antarctic margin reveals dynamics of ice sheet recession |
title_sort |
marine sediment record from the east antarctic margin reveals dynamics of ice sheet recession |
publishDate |
2006 |
url |
https://oro.open.ac.uk/6006/ http://www.gsajournals.org/perlserv/?request=get-document&doi=10.1130%2FGSAT01612A.1 |
long_lat |
ENVELOPE(76.833,76.833,-69.083,-69.083) ENVELOPE(146.000,146.000,-67.417,-67.417) ENVELOPE(76.342,76.342,-68.858,-68.858) |
geographic |
Antarctic The Antarctic Svenner Mertz-Ninnis Trough Svenner Channel |
geographic_facet |
Antarctic The Antarctic Svenner Mertz-Ninnis Trough Svenner Channel |
genre |
Antarc* Antarctic Ice Sheet Iceberg* |
genre_facet |
Antarc* Antarctic Ice Sheet Iceberg* |
op_relation |
Leventer, Amy; Domack, Eugene; Dunbar, Robert; Pike, Jennifer; Stickley, Catherine; Maddison, Eleanor <https://oro.open.ac.uk/view/person/ejm367.html>; Brachfeld, Stefanie; Manley, Patricia and McClennen, Charlie (2006). Marine sediment record from the East Antarctic margin reveals dynamics of ice sheet recession. GSA Today, 16(12) pp. 4–10. |
container_title |
GSA Today |
container_volume |
16 |
container_issue |
12 |
container_start_page |
4 |
_version_ |
1802649252788174848 |