Planktonic foraminiferal faunas and stable isotope ratios of sediments from the Benguela Upwelling System
Two sediment cores retrieved from the continental slope in the Benguela Upwelling System, GeoB 1706 (19°33.7'S 11°10.5'E) and GeoB 1711 (23°18.9'S, 12°22.6'E), reveal striking variations in planktonic foraminiferal abundances during the last 160,000 years. These fluctuations are...
Main Authors: | , , , , , |
---|---|
Format: | Dataset |
Language: | English |
Published: |
PANGAEA
1997
|
Subjects: | |
Online Access: | https://doi.pangaea.de/10.1594/PANGAEA.734360 https://doi.org/10.1594/PANGAEA.734360 |
id |
ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.734360 |
---|---|
record_format |
openpolar |
spelling |
ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.734360 2023-05-15T17:14:57+02:00 Planktonic foraminiferal faunas and stable isotope ratios of sediments from the Benguela Upwelling System Little, Mark G Schneider, Ralph R Kroon, Dick Price, B Bickert, Torsten Wefer, Gerold MEDIAN LATITUDE: -21.907708 * MEDIAN LONGITUDE: 11.926250 * SOUTH-BOUND LATITUDE: -23.316667 * WEST-BOUND LONGITUDE: 11.175000 * NORTH-BOUND LATITUDE: -19.561667 * EAST-BOUND LONGITUDE: 12.378333 * DATE/TIME START: 1992-01-08T00:00:00 * DATE/TIME END: 1992-01-11T00:00:00 1997-03-02 application/zip, 8 datasets https://doi.pangaea.de/10.1594/PANGAEA.734360 https://doi.org/10.1594/PANGAEA.734360 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.734360 https://doi.org/10.1594/PANGAEA.734360 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess CC-BY Supplement to: Little, Mark G; Schneider, Ralph R; Kroon, Dick; Price, B; Bickert, Torsten; Wefer, Gerold (1997): Rapid paleoceanographic changes in the Benguela Upwelling System for the last 160,000 years as indicated by abundances of planktonic foraminifera. Palaeogeography, Palaeoclimatology, Palaeoecology, 130(1-4), 135-161, https://doi.org/10.1016/S0031-0182(96)00136-8 GeoB GeoB1706-2 GeoB1711 GeoB1711-4 GeoB1711-5 Geosciences University of Bremen Giant box corer GKG Gravity corer (Kiel type) M20/2 Meteor (1986) Namibia Continental Margin Namibia continental slope SL Walvis Ridge Dataset 1997 ftpangaea https://doi.org/10.1594/PANGAEA.734360 https://doi.org/10.1016/S0031-0182(96)00136-8 2023-01-20T07:31:41Z Two sediment cores retrieved from the continental slope in the Benguela Upwelling System, GeoB 1706 (19°33.7'S 11°10.5'E) and GeoB 1711 (23°18.9'S, 12°22.6'E), reveal striking variations in planktonic foraminiferal abundances during the last 160,000 years. These fluctuations are investigated to assess changes in the intensity and position of the upwelling centres off Namibia. Four species make up over 95% of the variation within the core, and enable the record to be divided into episodes characterized by particular planktonic foraminiferal assemblages. The fossil assemblages have meaningful ecological significance when compared to those of the modern day and the relationship to their environment. The cold-water planktonic foraminifer, Neogloboquadrina pachyderma sinistral [N. pachyderma (s)], dominates the modern-day, coastal upwelling centres, and Neogloboquadrina pachyderma dextral and Globigerina bulloides characterize the fringes of the upwelling cells. Globorotalia inflata is representative of the offshore boundary between newly upwelled waters and the transitional, reduced nutrient levels of the subtropical waters. In the fossil record, episodes of high N. pachyderma (s) abundances are interpreted as evidence of increased upwelling intensity, and the associated increase in nutrients. The N. pachyderma (s) record suggests temporal shifts in the intensity of upwelling, and corresponding trophic domains, that do not follow the typical glacial-interglacial pattern. Periods of high N. pachyderma (s) abundance describe rapid, discrete events dominating isotope stages 3 and 2. The timing of these events correlates to the temporal shifts of the Angola-Benguela Front (Jansen et al., 1997) situated to the north of the Walvis Ridge. Absence of high abundances of N. pachyderma (s) from the continental slope of the southern Cape Basin indicates that Southern Ocean surface water advection has not exerted a major influence on the Benguela Current System. The coincidence of increased upwelling intensity with the movement ... Dataset Neogloboquadrina pachyderma Southern Ocean PANGAEA - Data Publisher for Earth & Environmental Science Southern Ocean ENVELOPE(11.175000,12.378333,-19.561667,-23.316667) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
GeoB GeoB1706-2 GeoB1711 GeoB1711-4 GeoB1711-5 Geosciences University of Bremen Giant box corer GKG Gravity corer (Kiel type) M20/2 Meteor (1986) Namibia Continental Margin Namibia continental slope SL Walvis Ridge |
spellingShingle |
GeoB GeoB1706-2 GeoB1711 GeoB1711-4 GeoB1711-5 Geosciences University of Bremen Giant box corer GKG Gravity corer (Kiel type) M20/2 Meteor (1986) Namibia Continental Margin Namibia continental slope SL Walvis Ridge Little, Mark G Schneider, Ralph R Kroon, Dick Price, B Bickert, Torsten Wefer, Gerold Planktonic foraminiferal faunas and stable isotope ratios of sediments from the Benguela Upwelling System |
topic_facet |
GeoB GeoB1706-2 GeoB1711 GeoB1711-4 GeoB1711-5 Geosciences University of Bremen Giant box corer GKG Gravity corer (Kiel type) M20/2 Meteor (1986) Namibia Continental Margin Namibia continental slope SL Walvis Ridge |
description |
Two sediment cores retrieved from the continental slope in the Benguela Upwelling System, GeoB 1706 (19°33.7'S 11°10.5'E) and GeoB 1711 (23°18.9'S, 12°22.6'E), reveal striking variations in planktonic foraminiferal abundances during the last 160,000 years. These fluctuations are investigated to assess changes in the intensity and position of the upwelling centres off Namibia. Four species make up over 95% of the variation within the core, and enable the record to be divided into episodes characterized by particular planktonic foraminiferal assemblages. The fossil assemblages have meaningful ecological significance when compared to those of the modern day and the relationship to their environment. The cold-water planktonic foraminifer, Neogloboquadrina pachyderma sinistral [N. pachyderma (s)], dominates the modern-day, coastal upwelling centres, and Neogloboquadrina pachyderma dextral and Globigerina bulloides characterize the fringes of the upwelling cells. Globorotalia inflata is representative of the offshore boundary between newly upwelled waters and the transitional, reduced nutrient levels of the subtropical waters. In the fossil record, episodes of high N. pachyderma (s) abundances are interpreted as evidence of increased upwelling intensity, and the associated increase in nutrients. The N. pachyderma (s) record suggests temporal shifts in the intensity of upwelling, and corresponding trophic domains, that do not follow the typical glacial-interglacial pattern. Periods of high N. pachyderma (s) abundance describe rapid, discrete events dominating isotope stages 3 and 2. The timing of these events correlates to the temporal shifts of the Angola-Benguela Front (Jansen et al., 1997) situated to the north of the Walvis Ridge. Absence of high abundances of N. pachyderma (s) from the continental slope of the southern Cape Basin indicates that Southern Ocean surface water advection has not exerted a major influence on the Benguela Current System. The coincidence of increased upwelling intensity with the movement ... |
format |
Dataset |
author |
Little, Mark G Schneider, Ralph R Kroon, Dick Price, B Bickert, Torsten Wefer, Gerold |
author_facet |
Little, Mark G Schneider, Ralph R Kroon, Dick Price, B Bickert, Torsten Wefer, Gerold |
author_sort |
Little, Mark G |
title |
Planktonic foraminiferal faunas and stable isotope ratios of sediments from the Benguela Upwelling System |
title_short |
Planktonic foraminiferal faunas and stable isotope ratios of sediments from the Benguela Upwelling System |
title_full |
Planktonic foraminiferal faunas and stable isotope ratios of sediments from the Benguela Upwelling System |
title_fullStr |
Planktonic foraminiferal faunas and stable isotope ratios of sediments from the Benguela Upwelling System |
title_full_unstemmed |
Planktonic foraminiferal faunas and stable isotope ratios of sediments from the Benguela Upwelling System |
title_sort |
planktonic foraminiferal faunas and stable isotope ratios of sediments from the benguela upwelling system |
publisher |
PANGAEA |
publishDate |
1997 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.734360 https://doi.org/10.1594/PANGAEA.734360 |
op_coverage |
MEDIAN LATITUDE: -21.907708 * MEDIAN LONGITUDE: 11.926250 * SOUTH-BOUND LATITUDE: -23.316667 * WEST-BOUND LONGITUDE: 11.175000 * NORTH-BOUND LATITUDE: -19.561667 * EAST-BOUND LONGITUDE: 12.378333 * DATE/TIME START: 1992-01-08T00:00:00 * DATE/TIME END: 1992-01-11T00:00:00 |
long_lat |
ENVELOPE(11.175000,12.378333,-19.561667,-23.316667) |
geographic |
Southern Ocean |
geographic_facet |
Southern Ocean |
genre |
Neogloboquadrina pachyderma Southern Ocean |
genre_facet |
Neogloboquadrina pachyderma Southern Ocean |
op_source |
Supplement to: Little, Mark G; Schneider, Ralph R; Kroon, Dick; Price, B; Bickert, Torsten; Wefer, Gerold (1997): Rapid paleoceanographic changes in the Benguela Upwelling System for the last 160,000 years as indicated by abundances of planktonic foraminifera. Palaeogeography, Palaeoclimatology, Palaeoecology, 130(1-4), 135-161, https://doi.org/10.1016/S0031-0182(96)00136-8 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.734360 https://doi.org/10.1594/PANGAEA.734360 |
op_rights |
CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1594/PANGAEA.734360 https://doi.org/10.1016/S0031-0182(96)00136-8 |
_version_ |
1766073065179971584 |