Late Quaternary planktonic foraminifera of ODP Hole 175-1087A
Planktonic foraminiferal assemblages from the upper Pleistocene part of Hole 1087A (0 to 12.1 meters below seafloor) are investigated to assess the role of global and local climate changes on surface circulation in the southern Benguela region. The benthic stable isotope record indicates that the st...
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.735232 2024-09-15T18:19:32+00:00 Late Quaternary planktonic foraminifera of ODP Hole 175-1087A Giraudeau, Jacques Pierre, Catherine Herve, Laurence LATITUDE: -31.464660 * LONGITUDE: 15.310880 * DATE/TIME START: 1997-10-03T02:10:00 * DATE/TIME END: 1997-10-03T22:25:00 2001 application/zip, 3 datasets https://doi.pangaea.de/10.1594/PANGAEA.735232 https://doi.org/10.1594/PANGAEA.735232 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.735232 https://doi.org/10.1594/PANGAEA.735232 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess Supplement to: Giraudeau, Jacques; Pierre, Catherine; Herve, Laurence (2001): A late Quaternary, high-resolution record of planktonic foraminiferal species distribution in the southern Benguela region: Site 1087. In: Wefer, G., Berger, W.H., and Richter, C. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 175, 1-26, https://doi.org/10.2973/odp.proc.sr.175.225.2001 175-1087A Benguela Current South Atlantic Ocean DRILL Drilling/drill rig Joides Resolution Leg175 Ocean Drilling Program ODP dataset publication series 2001 ftpangaea https://doi.org/10.1594/PANGAEA.73523210.2973/odp.proc.sr.175.225.2001 2024-07-24T02:31:20Z Planktonic foraminiferal assemblages from the upper Pleistocene part of Hole 1087A (0 to 12.1 meters below seafloor) are investigated to assess the role of global and local climate changes on surface circulation in the southern Benguela region. The benthic stable isotope record indicates that the studied interval is representative of the last four climatic cycles, that is, down to marine isotope Stage (MIS) 12. The species assemblages bear a clear transitional to subpolar character, with Neogloboquadrina pachyderma (d), Globorotalia inflata, and Globigerina bulloides, in order of decreasing abundance, as the dominant taxa. This species association presently characterizes the mixing domain of old upwelled and open ocean waters, seaward of the Benguela upwelling cells. Abundance variation of the dominant foraminiferal species roughly follows a glacial-interglacial pattern down to MIS 8, suggesting an alternation of upwelling strength and associated seaward extension of the belt of upwelled water as a response to global climate changes. This pattern is interrupted from ~250 ka down to MIS 12, where the phase relationship with global climate is ill defined and might be interpreted as a local response of the southern Benguela region to the mid-Brunhes event. Of particular interest is a single pulse of newly upwelled waters at the location of Site 1087 during early MIS 9 as indicated by a peak abundance of sinistral N. pachyderma (s). Variable input of warm, salty Indian Ocean thermocline waters into the southeast Atlantic, a key component of the Atlantic heat conveyor, is indicated by abundance changes of the tropical taxon Globorotalia menardii. From this tracer, we suggest that interocean exchange was hardly interrupted throughout the last 460 k.y., but was most effective at glacial terminations, particularly during Terminations I and II, as well as during the upper part of MIS 12. This maximum input of Indian Ocean waters around the southern tip of Africa is associated with the reseeding of G. menardii in the ... Other/Unknown Material Neogloboquadrina pachyderma Planktonic foraminifera South Atlantic Ocean PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(15.310880,15.310880,-31.464660,-31.464660) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
175-1087A Benguela Current South Atlantic Ocean DRILL Drilling/drill rig Joides Resolution Leg175 Ocean Drilling Program ODP |
spellingShingle |
175-1087A Benguela Current South Atlantic Ocean DRILL Drilling/drill rig Joides Resolution Leg175 Ocean Drilling Program ODP Giraudeau, Jacques Pierre, Catherine Herve, Laurence Late Quaternary planktonic foraminifera of ODP Hole 175-1087A |
topic_facet |
175-1087A Benguela Current South Atlantic Ocean DRILL Drilling/drill rig Joides Resolution Leg175 Ocean Drilling Program ODP |
description |
Planktonic foraminiferal assemblages from the upper Pleistocene part of Hole 1087A (0 to 12.1 meters below seafloor) are investigated to assess the role of global and local climate changes on surface circulation in the southern Benguela region. The benthic stable isotope record indicates that the studied interval is representative of the last four climatic cycles, that is, down to marine isotope Stage (MIS) 12. The species assemblages bear a clear transitional to subpolar character, with Neogloboquadrina pachyderma (d), Globorotalia inflata, and Globigerina bulloides, in order of decreasing abundance, as the dominant taxa. This species association presently characterizes the mixing domain of old upwelled and open ocean waters, seaward of the Benguela upwelling cells. Abundance variation of the dominant foraminiferal species roughly follows a glacial-interglacial pattern down to MIS 8, suggesting an alternation of upwelling strength and associated seaward extension of the belt of upwelled water as a response to global climate changes. This pattern is interrupted from ~250 ka down to MIS 12, where the phase relationship with global climate is ill defined and might be interpreted as a local response of the southern Benguela region to the mid-Brunhes event. Of particular interest is a single pulse of newly upwelled waters at the location of Site 1087 during early MIS 9 as indicated by a peak abundance of sinistral N. pachyderma (s). Variable input of warm, salty Indian Ocean thermocline waters into the southeast Atlantic, a key component of the Atlantic heat conveyor, is indicated by abundance changes of the tropical taxon Globorotalia menardii. From this tracer, we suggest that interocean exchange was hardly interrupted throughout the last 460 k.y., but was most effective at glacial terminations, particularly during Terminations I and II, as well as during the upper part of MIS 12. This maximum input of Indian Ocean waters around the southern tip of Africa is associated with the reseeding of G. menardii in the ... |
format |
Other/Unknown Material |
author |
Giraudeau, Jacques Pierre, Catherine Herve, Laurence |
author_facet |
Giraudeau, Jacques Pierre, Catherine Herve, Laurence |
author_sort |
Giraudeau, Jacques |
title |
Late Quaternary planktonic foraminifera of ODP Hole 175-1087A |
title_short |
Late Quaternary planktonic foraminifera of ODP Hole 175-1087A |
title_full |
Late Quaternary planktonic foraminifera of ODP Hole 175-1087A |
title_fullStr |
Late Quaternary planktonic foraminifera of ODP Hole 175-1087A |
title_full_unstemmed |
Late Quaternary planktonic foraminifera of ODP Hole 175-1087A |
title_sort |
late quaternary planktonic foraminifera of odp hole 175-1087a |
publisher |
PANGAEA |
publishDate |
2001 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.735232 https://doi.org/10.1594/PANGAEA.735232 |
op_coverage |
LATITUDE: -31.464660 * LONGITUDE: 15.310880 * DATE/TIME START: 1997-10-03T02:10:00 * DATE/TIME END: 1997-10-03T22:25:00 |
long_lat |
ENVELOPE(15.310880,15.310880,-31.464660,-31.464660) |
genre |
Neogloboquadrina pachyderma Planktonic foraminifera South Atlantic Ocean |
genre_facet |
Neogloboquadrina pachyderma Planktonic foraminifera South Atlantic Ocean |
op_source |
Supplement to: Giraudeau, Jacques; Pierre, Catherine; Herve, Laurence (2001): A late Quaternary, high-resolution record of planktonic foraminiferal species distribution in the southern Benguela region: Site 1087. In: Wefer, G., Berger, W.H., and Richter, C. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 175, 1-26, https://doi.org/10.2973/odp.proc.sr.175.225.2001 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.735232 https://doi.org/10.1594/PANGAEA.735232 |
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.73523210.2973/odp.proc.sr.175.225.2001 |
_version_ |
1810457885654646784 |