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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Geological Society of America
2006
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ftunivcardiff:oai:https://orca.cardiff.ac.uk:9464 2023-05-15T13:39:53+02:00 Marine sediment record from the East Antarctic margin reveals dynamics of ice sheet recession Leventer, A. Domack, E. Dunbar, R. Pike, Jennifer Stickley, C. Maddison, E. Brachfeld, S. Manley, P. McClennen, C. 2006-12 https://orca.cardiff.ac.uk/id/eprint/9464/ https://doi.org/10.1130/GSAT01612A.1 unknown Geological Society of America Leventer, A., Domack, E., Dunbar, R., Pike, Jennifer https://orca.cardiff.ac.uk/view/cardiffauthors/A0179070.html orcid:0000-0001-9415-6003 orcid:0000-0001-9415-6003, Stickley, C., Maddison, E., Brachfeld, S., Manley, P. and McClennen, C. 2006. Marine sediment record from the East Antarctic margin reveals dynamics of ice sheet recession. GSA Today 16 (12) , pp. 4-10. 10.1130/GSAT01612A.1 https://doi.org/10.1130/GSAT01612A.1 doi:10.1130/GSAT01612A.1 QE Geology Article PeerReviewed 2006 ftunivcardiff https://doi.org/10.1130/GSAT01612A.1 2022-10-20T22:34:04Z 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* Cardiff University: ORCA (Online Research @ Cardiff) Antarctic Mertz-Ninnis Trough ENVELOPE(146.000,146.000,-67.417,-67.417) Svenner ENVELOPE(76.833,76.833,-69.083,-69.083) Svenner Channel ENVELOPE(76.342,76.342,-68.858,-68.858) The Antarctic GSA Today 16 12 4 |
institution |
Open Polar |
collection |
Cardiff University: ORCA (Online Research @ Cardiff) |
op_collection_id |
ftunivcardiff |
language |
unknown |
topic |
QE Geology |
spellingShingle |
QE Geology Leventer, A. Domack, E. Dunbar, R. Pike, Jennifer Stickley, C. Maddison, E. Brachfeld, S. Manley, P. McClennen, C. Marine sediment record from the East Antarctic margin reveals dynamics of ice sheet recession |
topic_facet |
QE Geology |
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, A. Domack, E. Dunbar, R. Pike, Jennifer Stickley, C. Maddison, E. Brachfeld, S. Manley, P. McClennen, C. |
author_facet |
Leventer, A. Domack, E. Dunbar, R. Pike, Jennifer Stickley, C. Maddison, E. Brachfeld, S. Manley, P. McClennen, C. |
author_sort |
Leventer, A. |
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 |
publisher |
Geological Society of America |
publishDate |
2006 |
url |
https://orca.cardiff.ac.uk/id/eprint/9464/ https://doi.org/10.1130/GSAT01612A.1 |
long_lat |
ENVELOPE(146.000,146.000,-67.417,-67.417) ENVELOPE(76.833,76.833,-69.083,-69.083) ENVELOPE(76.342,76.342,-68.858,-68.858) |
geographic |
Antarctic Mertz-Ninnis Trough Svenner Svenner Channel The Antarctic |
geographic_facet |
Antarctic Mertz-Ninnis Trough Svenner Svenner Channel The Antarctic |
genre |
Antarc* Antarctic Ice Sheet Iceberg* |
genre_facet |
Antarc* Antarctic Ice Sheet Iceberg* |
op_relation |
Leventer, A., Domack, E., Dunbar, R., Pike, Jennifer https://orca.cardiff.ac.uk/view/cardiffauthors/A0179070.html orcid:0000-0001-9415-6003 orcid:0000-0001-9415-6003, Stickley, C., Maddison, E., Brachfeld, S., Manley, P. and McClennen, C. 2006. Marine sediment record from the East Antarctic margin reveals dynamics of ice sheet recession. GSA Today 16 (12) , pp. 4-10. 10.1130/GSAT01612A.1 https://doi.org/10.1130/GSAT01612A.1 doi:10.1130/GSAT01612A.1 |
op_doi |
https://doi.org/10.1130/GSAT01612A.1 |
container_title |
GSA Today |
container_volume |
16 |
container_issue |
12 |
container_start_page |
4 |
_version_ |
1766125805354614784 |