Isotopic interrogation of a suspected late Eocene glaciation
Ephemeral polar glaciations during the middle-to-late Eocene (48–34?Ma) have been proposed based on far-field ice volume proxy records and near-field glacigenic sediments, although the scale, timing, and duration of these events are poorly constrained. Here we confirm the existence of a transient co...
Published in: | Paleoceanography |
---|---|
Main Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2014
|
Subjects: | |
Online Access: | https://eprints.soton.ac.uk/366467/ |
id |
ftsouthampton:oai:eprints.soton.ac.uk:366467 |
---|---|
record_format |
openpolar |
spelling |
ftsouthampton:oai:eprints.soton.ac.uk:366467 2023-07-30T03:59:26+02:00 Isotopic interrogation of a suspected late Eocene glaciation Scher, Howie D. Bohaty, Steven M. Smith, Brian W. Munn, Gabrielle H. 2014-06 https://eprints.soton.ac.uk/366467/ English eng Scher, Howie D., Bohaty, Steven M., Smith, Brian W. and Munn, Gabrielle H. (2014) Isotopic interrogation of a suspected late Eocene glaciation. Paleoceanography, 29 (6), 628-644. (doi:10.1002/2014PA002648 <http://dx.doi.org/10.1002/2014PA002648>). Article PeerReviewed 2014 ftsouthampton https://doi.org/10.1002/2014PA002648 2023-07-09T21:53:44Z Ephemeral polar glaciations during the middle-to-late Eocene (48–34?Ma) have been proposed based on far-field ice volume proxy records and near-field glacigenic sediments, although the scale, timing, and duration of these events are poorly constrained. Here we confirm the existence of a transient cool event within a new high-resolution benthic foraminiferal ?18O record at Ocean Drilling Program (ODP) Site 738 (Kerguelen Plateau; Southern Ocean). This event, named the Priabonian oxygen isotope maximum (PrOM) Event, lasted ~140?kyr and is tentatively placed within magnetochron C17n.1n (~37.3?Ma) based on the correlation to ODP Site 689 (Maud Rise, Southern Ocean). A contemporaneous change in the provenance of sediments delivered to the Kerguelen Plateau occurs at the study site, determined from the <63?µm fraction of decarbonated and reductively leached sediment samples. Changes in the mixture of bottom waters, based on fossil fish tooth ?Nd, were less pronounced and slower relative to the benthic ?18O and terrigenous ?Nd changes. Terrigenous sediment ?Nd values rapidly shifted to less radiogenic signatures at the onset of the PrOM Event, indicating an abrupt change in provenance favoring ancient sources such as the Paleoproterozoic East Antarctic craton. Bottom water ?Nd reached a minimum value during the PrOM Event, although the shift begins much earlier than the terrigenous ?Nd excursion. The origin of the abrupt change in terrigenous sediment provenance is compatible with a change in Antarctic terrigenous sediment flux and/or source as opposed to a reorganization of ocean currents. A change in terrigenous flux and/or source of Antarctic sediments during the oxygen isotope maximum suggests a combination of cooling and ice growth in East Antarctica during the early late Eocene. Article in Journal/Newspaper Antarc* Antarctic Antarctica East Antarctica Southern Ocean University of Southampton: e-Prints Soton Antarctic East Antarctica Kerguelen Maud Rise ENVELOPE(3.000,3.000,-66.000,-66.000) Southern Ocean Paleoceanography 29 6 628 644 |
institution |
Open Polar |
collection |
University of Southampton: e-Prints Soton |
op_collection_id |
ftsouthampton |
language |
English |
description |
Ephemeral polar glaciations during the middle-to-late Eocene (48–34?Ma) have been proposed based on far-field ice volume proxy records and near-field glacigenic sediments, although the scale, timing, and duration of these events are poorly constrained. Here we confirm the existence of a transient cool event within a new high-resolution benthic foraminiferal ?18O record at Ocean Drilling Program (ODP) Site 738 (Kerguelen Plateau; Southern Ocean). This event, named the Priabonian oxygen isotope maximum (PrOM) Event, lasted ~140?kyr and is tentatively placed within magnetochron C17n.1n (~37.3?Ma) based on the correlation to ODP Site 689 (Maud Rise, Southern Ocean). A contemporaneous change in the provenance of sediments delivered to the Kerguelen Plateau occurs at the study site, determined from the <63?µm fraction of decarbonated and reductively leached sediment samples. Changes in the mixture of bottom waters, based on fossil fish tooth ?Nd, were less pronounced and slower relative to the benthic ?18O and terrigenous ?Nd changes. Terrigenous sediment ?Nd values rapidly shifted to less radiogenic signatures at the onset of the PrOM Event, indicating an abrupt change in provenance favoring ancient sources such as the Paleoproterozoic East Antarctic craton. Bottom water ?Nd reached a minimum value during the PrOM Event, although the shift begins much earlier than the terrigenous ?Nd excursion. The origin of the abrupt change in terrigenous sediment provenance is compatible with a change in Antarctic terrigenous sediment flux and/or source as opposed to a reorganization of ocean currents. A change in terrigenous flux and/or source of Antarctic sediments during the oxygen isotope maximum suggests a combination of cooling and ice growth in East Antarctica during the early late Eocene. |
format |
Article in Journal/Newspaper |
author |
Scher, Howie D. Bohaty, Steven M. Smith, Brian W. Munn, Gabrielle H. |
spellingShingle |
Scher, Howie D. Bohaty, Steven M. Smith, Brian W. Munn, Gabrielle H. Isotopic interrogation of a suspected late Eocene glaciation |
author_facet |
Scher, Howie D. Bohaty, Steven M. Smith, Brian W. Munn, Gabrielle H. |
author_sort |
Scher, Howie D. |
title |
Isotopic interrogation of a suspected late Eocene glaciation |
title_short |
Isotopic interrogation of a suspected late Eocene glaciation |
title_full |
Isotopic interrogation of a suspected late Eocene glaciation |
title_fullStr |
Isotopic interrogation of a suspected late Eocene glaciation |
title_full_unstemmed |
Isotopic interrogation of a suspected late Eocene glaciation |
title_sort |
isotopic interrogation of a suspected late eocene glaciation |
publishDate |
2014 |
url |
https://eprints.soton.ac.uk/366467/ |
long_lat |
ENVELOPE(3.000,3.000,-66.000,-66.000) |
geographic |
Antarctic East Antarctica Kerguelen Maud Rise Southern Ocean |
geographic_facet |
Antarctic East Antarctica Kerguelen Maud Rise Southern Ocean |
genre |
Antarc* Antarctic Antarctica East Antarctica Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica Southern Ocean |
op_relation |
Scher, Howie D., Bohaty, Steven M., Smith, Brian W. and Munn, Gabrielle H. (2014) Isotopic interrogation of a suspected late Eocene glaciation. Paleoceanography, 29 (6), 628-644. (doi:10.1002/2014PA002648 <http://dx.doi.org/10.1002/2014PA002648>). |
op_doi |
https://doi.org/10.1002/2014PA002648 |
container_title |
Paleoceanography |
container_volume |
29 |
container_issue |
6 |
container_start_page |
628 |
op_container_end_page |
644 |
_version_ |
1772810254146338816 |