Age model for the time between 3.45 and 2.45 Ma of ODP Site 189-1172
Calcareous nannoplankton assemblages and benthic d18O isotopes of Pliocene deep-sea sediments of ODP site 1172 (East of Tasmania) have been studied to improve our knowledge of the Southern Ocean paleoceanography. Our study site is located just north of the Subtropical Front (STF), an ideal setting t...
Main Authors: | , , , |
---|---|
Format: | Other/Unknown Material |
Language: | English |
Published: |
PANGAEA
2013
|
Subjects: | |
Online Access: | https://doi.pangaea.de/10.1594/PANGAEA.811548 https://doi.org/10.1594/PANGAEA.811548 |
id |
ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.811548 |
---|---|
record_format |
openpolar |
spelling |
ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.811548 2024-09-15T18:37:25+00:00 Age model for the time between 3.45 and 2.45 Ma of ODP Site 189-1172 Ballegeer, Anne-Marie Flores, José-Abel Sierro, Francisco Javier Andersen, Nils MEDIAN LATITUDE: -43.959633 * MEDIAN LONGITUDE: 149.928347 * SOUTH-BOUND LATITUDE: -43.959750 * WEST-BOUND LONGITUDE: 149.928260 * NORTH-BOUND LATITUDE: -43.959517 * EAST-BOUND LONGITUDE: 149.928433 * DATE/TIME START: 2000-04-22T00:00:00 * DATE/TIME END: 2000-04-26T09:30:00 2013 application/zip, 2 datasets https://doi.pangaea.de/10.1594/PANGAEA.811548 https://doi.org/10.1594/PANGAEA.811548 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.811548 https://doi.org/10.1594/PANGAEA.811548 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess Supplement to: Ballegeer, Anne-Marie; Flores, José-Abel; Sierro, Francisco Javier; Andersen, Nils (2012): Monitoring fluctuations of the Subtropical Front in the Tasman Sea between 3.45 and 2.45Ma (ODP site 1172). Palaeogeography, Palaeoclimatology, Palaeoecology, 313-314, 215-224, https://doi.org/10.1016/j.palaeo.2011.11.001 Ocean Drilling Program ODP dataset publication series 2013 ftpangaea https://doi.org/10.1594/PANGAEA.81154810.1016/j.palaeo.2011.11.001 2024-07-24T02:31:21Z Calcareous nannoplankton assemblages and benthic d18O isotopes of Pliocene deep-sea sediments of ODP site 1172 (East of Tasmania) have been studied to improve our knowledge of the Southern Ocean paleoceanography. Our study site is located just north of the Subtropical Front (STF), an ideal setting to monitor migrations of the STF during our study period, between 3.45 and 2.45 Ma. The assemblage identified at ODP site 1172 has been interpreted as characteristic for the transitional zone water mass, located south of the STF, based on: (i) the low abundances (< 1%) of subtropical taxa, (ii) relatively high percentages of Coccolithus pelagicus, a subpolar type species, (iii) abundances from 2-10% of Calcidiscus leptoporus, a species that frequently inhabits the zone south of the STF and (iv) the high abundances of small Noelaerhabdaceae which at present dominates the zone south of the STF. Across our interval the calcareous nannoplankton manifests glacial-interglacial variability. We have identified cold events, characterized by high abundances of C. pelagicus which coincide with glacial periods, except during G7. After 3.1 Ma cold events are more frequent, in concordance with global cooling trends. Around 2.75 Ma, the interglacial stage G7 is characterized by anomalous low temperatures which most likely are linked to definite closure of the Central American Seaway (CAS), an event that is believed to have had global consequences. A gradual increase of very small Reticulofenestra across our section marks a significant trend in the small Noelaerhabdaceae species group and has been linked to a general enhanced mixing of the water column in agreement with previous studies. It is suggested that a rapid decline of small Gephyrocapsa after isotopic stage G7 might be related to the cooling observed in our study site after the closure of the CAS. Other/Unknown Material Southern Ocean PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(149.928260,149.928433,-43.959517,-43.959750) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
Ocean Drilling Program ODP |
spellingShingle |
Ocean Drilling Program ODP Ballegeer, Anne-Marie Flores, José-Abel Sierro, Francisco Javier Andersen, Nils Age model for the time between 3.45 and 2.45 Ma of ODP Site 189-1172 |
topic_facet |
Ocean Drilling Program ODP |
description |
Calcareous nannoplankton assemblages and benthic d18O isotopes of Pliocene deep-sea sediments of ODP site 1172 (East of Tasmania) have been studied to improve our knowledge of the Southern Ocean paleoceanography. Our study site is located just north of the Subtropical Front (STF), an ideal setting to monitor migrations of the STF during our study period, between 3.45 and 2.45 Ma. The assemblage identified at ODP site 1172 has been interpreted as characteristic for the transitional zone water mass, located south of the STF, based on: (i) the low abundances (< 1%) of subtropical taxa, (ii) relatively high percentages of Coccolithus pelagicus, a subpolar type species, (iii) abundances from 2-10% of Calcidiscus leptoporus, a species that frequently inhabits the zone south of the STF and (iv) the high abundances of small Noelaerhabdaceae which at present dominates the zone south of the STF. Across our interval the calcareous nannoplankton manifests glacial-interglacial variability. We have identified cold events, characterized by high abundances of C. pelagicus which coincide with glacial periods, except during G7. After 3.1 Ma cold events are more frequent, in concordance with global cooling trends. Around 2.75 Ma, the interglacial stage G7 is characterized by anomalous low temperatures which most likely are linked to definite closure of the Central American Seaway (CAS), an event that is believed to have had global consequences. A gradual increase of very small Reticulofenestra across our section marks a significant trend in the small Noelaerhabdaceae species group and has been linked to a general enhanced mixing of the water column in agreement with previous studies. It is suggested that a rapid decline of small Gephyrocapsa after isotopic stage G7 might be related to the cooling observed in our study site after the closure of the CAS. |
format |
Other/Unknown Material |
author |
Ballegeer, Anne-Marie Flores, José-Abel Sierro, Francisco Javier Andersen, Nils |
author_facet |
Ballegeer, Anne-Marie Flores, José-Abel Sierro, Francisco Javier Andersen, Nils |
author_sort |
Ballegeer, Anne-Marie |
title |
Age model for the time between 3.45 and 2.45 Ma of ODP Site 189-1172 |
title_short |
Age model for the time between 3.45 and 2.45 Ma of ODP Site 189-1172 |
title_full |
Age model for the time between 3.45 and 2.45 Ma of ODP Site 189-1172 |
title_fullStr |
Age model for the time between 3.45 and 2.45 Ma of ODP Site 189-1172 |
title_full_unstemmed |
Age model for the time between 3.45 and 2.45 Ma of ODP Site 189-1172 |
title_sort |
age model for the time between 3.45 and 2.45 ma of odp site 189-1172 |
publisher |
PANGAEA |
publishDate |
2013 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.811548 https://doi.org/10.1594/PANGAEA.811548 |
op_coverage |
MEDIAN LATITUDE: -43.959633 * MEDIAN LONGITUDE: 149.928347 * SOUTH-BOUND LATITUDE: -43.959750 * WEST-BOUND LONGITUDE: 149.928260 * NORTH-BOUND LATITUDE: -43.959517 * EAST-BOUND LONGITUDE: 149.928433 * DATE/TIME START: 2000-04-22T00:00:00 * DATE/TIME END: 2000-04-26T09:30:00 |
long_lat |
ENVELOPE(149.928260,149.928433,-43.959517,-43.959750) |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_source |
Supplement to: Ballegeer, Anne-Marie; Flores, José-Abel; Sierro, Francisco Javier; Andersen, Nils (2012): Monitoring fluctuations of the Subtropical Front in the Tasman Sea between 3.45 and 2.45Ma (ODP site 1172). Palaeogeography, Palaeoclimatology, Palaeoecology, 313-314, 215-224, https://doi.org/10.1016/j.palaeo.2011.11.001 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.811548 https://doi.org/10.1594/PANGAEA.811548 |
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.81154810.1016/j.palaeo.2011.11.001 |
_version_ |
1810481785326272512 |