Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica - Part 1: Insights from late Oligocene astronomically paced contourite sedimentation
Antarctic ice sheet and Southern Ocean paleoceanographic configurations during the late Oligocene are not well resolved. They are however important to understand the influence of high-latitude Southern Hemisphere feedbacks on global climate under CO scenarios (between 400 and 750 ppm) projected by t...
Published in: | Climate of the Past |
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European Geosciences Union
2018
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Online Access: | http://hdl.handle.net/10261/214722 https://doi.org/10.5194/cp-14-991-2018 https://doi.org/10.13039/501100003329 https://doi.org/10.13039/501100000780 https://doi.org/10.13039/501100000270 |
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ftcsic:oai:digital.csic.es:10261/214722 2024-02-11T09:58:28+01:00 Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica - Part 1: Insights from late Oligocene astronomically paced contourite sedimentation Salabarnada, Ariadna Escutia, Carlota Röhl, Ursula Nelson, C. Hans McKay, Robert M. Jiménez Espejo, Francisco J. Bijl, Peter K. Hartman, Julian D. Strother, Stephanie L. Salzmann, Ulrich Evangelinos, Dimitris López-Quirós, Adrián Flores, José Abel Sangiorgi, Francesca Ikehara, Minoru Brinkhuis, Henk Ministerio de Economía y Competitividad (España) European Commission Natural Environment Research Council (UK) 2018-07-10 http://hdl.handle.net/10261/214722 https://doi.org/10.5194/cp-14-991-2018 https://doi.org/10.13039/501100003329 https://doi.org/10.13039/501100000780 https://doi.org/10.13039/501100000270 unknown European Geosciences Union #PLACEHOLDER_PARENT_METADATA_VALUE# info:eu-repo/grantAgreement/MINECO/Plan Estatal de Investigación Científica y Técnica y de Innovación 2013-2016/CTM 2011-24079 info:eu-repo/grantAgreement/MINECO/Plan Estatal de Investigación Científica y Técnica y de Innovación 2013-2016/CTM2014-60451-C2-1-P http://dx.doi.org/10.5194/cp-14-991-2018 Sí doi:10.5194/cp-14-991-2018 issn: 1814-9332 Climate of the Past 14 (7): 991-1014 (2018) http://hdl.handle.net/10261/214722 http://dx.doi.org/10.13039/501100003329 http://dx.doi.org/10.13039/501100000780 http://dx.doi.org/10.13039/501100000270 open artículo http://purl.org/coar/resource_type/c_6501 2018 ftcsic https://doi.org/10.5194/cp-14-991-201810.13039/50110000332910.13039/50110000078010.13039/501100000270 2024-01-16T10:55:31Z Antarctic ice sheet and Southern Ocean paleoceanographic configurations during the late Oligocene are not well resolved. They are however important to understand the influence of high-latitude Southern Hemisphere feedbacks on global climate under CO scenarios (between 400 and 750 ppm) projected by the IPCC for this century, assuming unabated CO emissions. Sediments recovered by the Integrated Ocean Drilling Program (IODP) at Site U1356, offshore of the Wilkes Land margin in East Antarctica, provide an opportunity to study ice sheet and paleoceanographic configurations during the late Oligocene (26-25 Ma). Our study, based on a combination of sediment facies analysis, magnetic susceptibility, density, and X-ray fluorescence geochemical data, shows that glacial and interglacial sediments are continuously reworked by bottom currents, with maximum velocities occurring during the interglacial periods. Glacial sediments record poorly ventilated, low-oxygenation bottom water conditions, interpreted as resulting from a northward shift of westerly winds and surface oceanic fronts. Interglacial sediments record more oxygenated and ventilated bottom water conditions and strong current velocities, which suggests enhanced mixing of the water masses as a result of a southward shift of the polar front. Intervals with preserved carbonated nannofossils within some of the interglacial facies are interpreted as forming under warmer paleoclimatic conditions when less corrosive warmer northern component water (e.g., North Atlantic sourced deep water) had a greater influence on the site. Spectral analysis on the late Oligocene sediment interval shows that the glacial-interglacial cyclicity and related displacements of the Southern Ocean frontal systems between 26 and 25Ma were forced mainly by obliquity. The paucity of iceberg-rafted debris (IRD) throughout the studied interval contrasts with earlier Oligocene and post-Miocene Climate Optimum sections from Site U1356 and with late Oligocene strata from the Ross Sea, which contain IRD ... Article in Journal/Newspaper Antarc* Antarctic Antarctica East Antarctica Ice Sheet Iceberg* North Atlantic Ross Sea Southern Ocean Wilkes Land Digital.CSIC (Spanish National Research Council) Antarctic East Antarctica Ross Sea Southern Ocean Wilkes Land ENVELOPE(120.000,120.000,-69.000,-69.000) Climate of the Past 14 7 991 1014 |
institution |
Open Polar |
collection |
Digital.CSIC (Spanish National Research Council) |
op_collection_id |
ftcsic |
language |
unknown |
description |
Antarctic ice sheet and Southern Ocean paleoceanographic configurations during the late Oligocene are not well resolved. They are however important to understand the influence of high-latitude Southern Hemisphere feedbacks on global climate under CO scenarios (between 400 and 750 ppm) projected by the IPCC for this century, assuming unabated CO emissions. Sediments recovered by the Integrated Ocean Drilling Program (IODP) at Site U1356, offshore of the Wilkes Land margin in East Antarctica, provide an opportunity to study ice sheet and paleoceanographic configurations during the late Oligocene (26-25 Ma). Our study, based on a combination of sediment facies analysis, magnetic susceptibility, density, and X-ray fluorescence geochemical data, shows that glacial and interglacial sediments are continuously reworked by bottom currents, with maximum velocities occurring during the interglacial periods. Glacial sediments record poorly ventilated, low-oxygenation bottom water conditions, interpreted as resulting from a northward shift of westerly winds and surface oceanic fronts. Interglacial sediments record more oxygenated and ventilated bottom water conditions and strong current velocities, which suggests enhanced mixing of the water masses as a result of a southward shift of the polar front. Intervals with preserved carbonated nannofossils within some of the interglacial facies are interpreted as forming under warmer paleoclimatic conditions when less corrosive warmer northern component water (e.g., North Atlantic sourced deep water) had a greater influence on the site. Spectral analysis on the late Oligocene sediment interval shows that the glacial-interglacial cyclicity and related displacements of the Southern Ocean frontal systems between 26 and 25Ma were forced mainly by obliquity. The paucity of iceberg-rafted debris (IRD) throughout the studied interval contrasts with earlier Oligocene and post-Miocene Climate Optimum sections from Site U1356 and with late Oligocene strata from the Ross Sea, which contain IRD ... |
author2 |
Ministerio de Economía y Competitividad (España) European Commission Natural Environment Research Council (UK) |
format |
Article in Journal/Newspaper |
author |
Salabarnada, Ariadna Escutia, Carlota Röhl, Ursula Nelson, C. Hans McKay, Robert M. Jiménez Espejo, Francisco J. Bijl, Peter K. Hartman, Julian D. Strother, Stephanie L. Salzmann, Ulrich Evangelinos, Dimitris López-Quirós, Adrián Flores, José Abel Sangiorgi, Francesca Ikehara, Minoru Brinkhuis, Henk |
spellingShingle |
Salabarnada, Ariadna Escutia, Carlota Röhl, Ursula Nelson, C. Hans McKay, Robert M. Jiménez Espejo, Francisco J. Bijl, Peter K. Hartman, Julian D. Strother, Stephanie L. Salzmann, Ulrich Evangelinos, Dimitris López-Quirós, Adrián Flores, José Abel Sangiorgi, Francesca Ikehara, Minoru Brinkhuis, Henk Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica - Part 1: Insights from late Oligocene astronomically paced contourite sedimentation |
author_facet |
Salabarnada, Ariadna Escutia, Carlota Röhl, Ursula Nelson, C. Hans McKay, Robert M. Jiménez Espejo, Francisco J. Bijl, Peter K. Hartman, Julian D. Strother, Stephanie L. Salzmann, Ulrich Evangelinos, Dimitris López-Quirós, Adrián Flores, José Abel Sangiorgi, Francesca Ikehara, Minoru Brinkhuis, Henk |
author_sort |
Salabarnada, Ariadna |
title |
Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica - Part 1: Insights from late Oligocene astronomically paced contourite sedimentation |
title_short |
Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica - Part 1: Insights from late Oligocene astronomically paced contourite sedimentation |
title_full |
Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica - Part 1: Insights from late Oligocene astronomically paced contourite sedimentation |
title_fullStr |
Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica - Part 1: Insights from late Oligocene astronomically paced contourite sedimentation |
title_full_unstemmed |
Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica - Part 1: Insights from late Oligocene astronomically paced contourite sedimentation |
title_sort |
paleoceanography and ice sheet variability offshore wilkes land, antarctica - part 1: insights from late oligocene astronomically paced contourite sedimentation |
publisher |
European Geosciences Union |
publishDate |
2018 |
url |
http://hdl.handle.net/10261/214722 https://doi.org/10.5194/cp-14-991-2018 https://doi.org/10.13039/501100003329 https://doi.org/10.13039/501100000780 https://doi.org/10.13039/501100000270 |
long_lat |
ENVELOPE(120.000,120.000,-69.000,-69.000) |
geographic |
Antarctic East Antarctica Ross Sea Southern Ocean Wilkes Land |
geographic_facet |
Antarctic East Antarctica Ross Sea Southern Ocean Wilkes Land |
genre |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet Iceberg* North Atlantic Ross Sea Southern Ocean Wilkes Land |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet Iceberg* North Atlantic Ross Sea Southern Ocean Wilkes Land |
op_relation |
#PLACEHOLDER_PARENT_METADATA_VALUE# info:eu-repo/grantAgreement/MINECO/Plan Estatal de Investigación Científica y Técnica y de Innovación 2013-2016/CTM 2011-24079 info:eu-repo/grantAgreement/MINECO/Plan Estatal de Investigación Científica y Técnica y de Innovación 2013-2016/CTM2014-60451-C2-1-P http://dx.doi.org/10.5194/cp-14-991-2018 Sí doi:10.5194/cp-14-991-2018 issn: 1814-9332 Climate of the Past 14 (7): 991-1014 (2018) http://hdl.handle.net/10261/214722 http://dx.doi.org/10.13039/501100003329 http://dx.doi.org/10.13039/501100000780 http://dx.doi.org/10.13039/501100000270 |
op_rights |
open |
op_doi |
https://doi.org/10.5194/cp-14-991-201810.13039/50110000332910.13039/50110000078010.13039/501100000270 |
container_title |
Climate of the Past |
container_volume |
14 |
container_issue |
7 |
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991 |
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1014 |
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