Stable carbon and oxygen isotope ratios of benthic foraminifera from Paleocene to Oligocene sediments
Benthic oxygen and carbon isotopic results from a depth transect on Maud Rise, Antarctica, provide the first evidence for Warm Saline Deep Water (WSDW) in the Paleogene oceans. Distinct reversals occur in the oxygen isotopic gradient between the shallower Hole 689B (Eocene depth ~1400 m; present-day...
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.726317 2024-09-15T17:42:32+00:00 Stable carbon and oxygen isotope ratios of benthic foraminifera from Paleocene to Oligocene sediments Kennett, James P Stott, Lowell D MEDIAN LATITUDE: -64.839000 * MEDIAN LONGITUDE: 2.152400 * SOUTH-BOUND LATITUDE: -65.161000 * WEST-BOUND LONGITUDE: 1.204900 * NORTH-BOUND LATITUDE: -64.517000 * EAST-BOUND LONGITUDE: 3.099900 * DATE/TIME START: 1987-01-16T08:00:00 * DATE/TIME END: 1987-01-21T07:00:00 1990 application/zip, 2 datasets https://doi.pangaea.de/10.1594/PANGAEA.726317 https://doi.org/10.1594/PANGAEA.726317 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.726317 https://doi.org/10.1594/PANGAEA.726317 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess Supplement to: Kennett, James P; Stott, Lowell D (1990): Proteus and Proto-Oceanus: ancestral Paleogene oceans as revealed from Antarctic stable isotopic results; ODP Leg 113. In: Barker, PF; Kennett, JP; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 113, 865-878, https://doi.org/10.2973/odp.proc.sr.113.188.1990 113-689B 113-690B DRILL Drilling/drill rig Joides Resolution Leg113 Ocean Drilling Program ODP South Atlantic Ocean dataset publication series 1990 ftpangaea https://doi.org/10.1594/PANGAEA.72631710.2973/odp.proc.sr.113.188.1990 2024-07-24T02:31:20Z Benthic oxygen and carbon isotopic results from a depth transect on Maud Rise, Antarctica, provide the first evidence for Warm Saline Deep Water (WSDW) in the Paleogene oceans. Distinct reversals occur in the oxygen isotopic gradient between the shallower Hole 689B (Eocene depth ~1400 m; present-day depth 2080 m) and the deeper Hole 690B (Eocene depth ~2250 m; present-day depth 2914 m). The isotopic reversals, well developed by at least 46 Ma (middle middle Eocene), existed for much of the remaining Paleogene. We do not consider these reversals to be artifacts of differential diagenesis between the two sites or to have resulted from other potentially complicating factors. This being so, the results show that deep waters at Hole 690B were significantly warmer than deep waters at the shallower Hole 689B. A progressive decrease and eventual reversal in benthic to planktonic delta18O gradients in Hole 690B, demonstrate that the deeper waters became warmer relative to Antarctic surface waters during the Eocene. The warmer deep waters of the Paleogene are inferred to have been produced at middle to low latitudes, probably in the Tethyan region which contained extensive shallow-water platforms, ideal sites for the formation of high salinity water through evaporative processes. The ocean during the Eocene, and perhaps the Paleocene, is inferred to have been two-layered, consisting of warm, saline deep waters formed at low latitudes and overlain by cooler waters formed at high latitudes. This thermospheric ocean, dominated by halothermal circulation we name Proteus. The Neogene and modern psychrospheric ocean Oceanus is dominated by thermohaline circulation of deep waters largely formed at high latitudes. An intermediate condition existed during the Oligocene, with a three-layered ocean that consisted of cold, dense deep waters formed in the Antarctic (Proto-AABW), overlain by warm, saline deep waters from low latitudes, and in turn overlain by cool waters formed in the polar regions. This we name Proto-oceanus which ... Other/Unknown Material Antarc* Antarctic Antarctica South Atlantic Ocean PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(1.204900,3.099900,-64.517000,-65.161000) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
113-689B 113-690B DRILL Drilling/drill rig Joides Resolution Leg113 Ocean Drilling Program ODP South Atlantic Ocean |
spellingShingle |
113-689B 113-690B DRILL Drilling/drill rig Joides Resolution Leg113 Ocean Drilling Program ODP South Atlantic Ocean Kennett, James P Stott, Lowell D Stable carbon and oxygen isotope ratios of benthic foraminifera from Paleocene to Oligocene sediments |
topic_facet |
113-689B 113-690B DRILL Drilling/drill rig Joides Resolution Leg113 Ocean Drilling Program ODP South Atlantic Ocean |
description |
Benthic oxygen and carbon isotopic results from a depth transect on Maud Rise, Antarctica, provide the first evidence for Warm Saline Deep Water (WSDW) in the Paleogene oceans. Distinct reversals occur in the oxygen isotopic gradient between the shallower Hole 689B (Eocene depth ~1400 m; present-day depth 2080 m) and the deeper Hole 690B (Eocene depth ~2250 m; present-day depth 2914 m). The isotopic reversals, well developed by at least 46 Ma (middle middle Eocene), existed for much of the remaining Paleogene. We do not consider these reversals to be artifacts of differential diagenesis between the two sites or to have resulted from other potentially complicating factors. This being so, the results show that deep waters at Hole 690B were significantly warmer than deep waters at the shallower Hole 689B. A progressive decrease and eventual reversal in benthic to planktonic delta18O gradients in Hole 690B, demonstrate that the deeper waters became warmer relative to Antarctic surface waters during the Eocene. The warmer deep waters of the Paleogene are inferred to have been produced at middle to low latitudes, probably in the Tethyan region which contained extensive shallow-water platforms, ideal sites for the formation of high salinity water through evaporative processes. The ocean during the Eocene, and perhaps the Paleocene, is inferred to have been two-layered, consisting of warm, saline deep waters formed at low latitudes and overlain by cooler waters formed at high latitudes. This thermospheric ocean, dominated by halothermal circulation we name Proteus. The Neogene and modern psychrospheric ocean Oceanus is dominated by thermohaline circulation of deep waters largely formed at high latitudes. An intermediate condition existed during the Oligocene, with a three-layered ocean that consisted of cold, dense deep waters formed in the Antarctic (Proto-AABW), overlain by warm, saline deep waters from low latitudes, and in turn overlain by cool waters formed in the polar regions. This we name Proto-oceanus which ... |
format |
Other/Unknown Material |
author |
Kennett, James P Stott, Lowell D |
author_facet |
Kennett, James P Stott, Lowell D |
author_sort |
Kennett, James P |
title |
Stable carbon and oxygen isotope ratios of benthic foraminifera from Paleocene to Oligocene sediments |
title_short |
Stable carbon and oxygen isotope ratios of benthic foraminifera from Paleocene to Oligocene sediments |
title_full |
Stable carbon and oxygen isotope ratios of benthic foraminifera from Paleocene to Oligocene sediments |
title_fullStr |
Stable carbon and oxygen isotope ratios of benthic foraminifera from Paleocene to Oligocene sediments |
title_full_unstemmed |
Stable carbon and oxygen isotope ratios of benthic foraminifera from Paleocene to Oligocene sediments |
title_sort |
stable carbon and oxygen isotope ratios of benthic foraminifera from paleocene to oligocene sediments |
publisher |
PANGAEA |
publishDate |
1990 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.726317 https://doi.org/10.1594/PANGAEA.726317 |
op_coverage |
MEDIAN LATITUDE: -64.839000 * MEDIAN LONGITUDE: 2.152400 * SOUTH-BOUND LATITUDE: -65.161000 * WEST-BOUND LONGITUDE: 1.204900 * NORTH-BOUND LATITUDE: -64.517000 * EAST-BOUND LONGITUDE: 3.099900 * DATE/TIME START: 1987-01-16T08:00:00 * DATE/TIME END: 1987-01-21T07:00:00 |
long_lat |
ENVELOPE(1.204900,3.099900,-64.517000,-65.161000) |
genre |
Antarc* Antarctic Antarctica South Atlantic Ocean |
genre_facet |
Antarc* Antarctic Antarctica South Atlantic Ocean |
op_source |
Supplement to: Kennett, James P; Stott, Lowell D (1990): Proteus and Proto-Oceanus: ancestral Paleogene oceans as revealed from Antarctic stable isotopic results; ODP Leg 113. In: Barker, PF; Kennett, JP; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 113, 865-878, https://doi.org/10.2973/odp.proc.sr.113.188.1990 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.726317 https://doi.org/10.1594/PANGAEA.726317 |
op_rights |
CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1594/PANGAEA.72631710.2973/odp.proc.sr.113.188.1990 |
_version_ |
1810489147939356672 |