Calcareous nannofossil biostratigraphy of ODP Leg 108 sediments
Calcareous nannofossils were examined from the 400 cores recovered at 12 sites during Ocean Drilling Program Leg 108 in the eastern equatorial Atlantic Ocean and along the northwest African margin, representing a transect spanning 24° of latitude. Thirty calcareous nannofossil biohorizons were recog...
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1989
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.746289 2024-09-15T18:24:24+00:00 Calcareous nannofossil biostratigraphy of ODP Leg 108 sediments Manivit, Helene MEDIAN LATITUDE: 7.874669 * MEDIAN LONGITUDE: -19.084008 * SOUTH-BOUND LATITUDE: -1.390200 * WEST-BOUND LONGITUDE: -23.227500 * NORTH-BOUND LATITUDE: 21.331500 * EAST-BOUND LONGITUDE: -11.739200 * DATE/TIME START: 1986-02-27T22:15:00 * DATE/TIME END: 1986-04-14T11:30:00 1989 application/zip, 13 datasets https://doi.pangaea.de/10.1594/PANGAEA.746289 https://doi.org/10.1594/PANGAEA.746289 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.746289 https://doi.org/10.1594/PANGAEA.746289 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess Supplement to: Manivit, Helene (1989): Calcareous nannofossil biostratigraphy of Leg 108 sediments. In: Ruddiman, W; Sarnthein, M; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 108, 35-69, https://doi.org/10.2973/odp.proc.sr.108.126.1989 108-657A 108-658A 108-659A 108-660A 108-661A 108-662A 108-663A 108-664A 108-665A 108-666A 108-667A 108-668A Canarias Sea DRILL Drilling/drill rig Joides Resolution Leg108 North Atlantic Ocean Ocean Drilling Program ODP South Atlantic Ocean dataset publication series 1989 ftpangaea https://doi.org/10.1594/PANGAEA.74628910.2973/odp.proc.sr.108.126.1989 2024-08-21T00:02:25Z Calcareous nannofossils were examined from the 400 cores recovered at 12 sites during Ocean Drilling Program Leg 108 in the eastern equatorial Atlantic Ocean and along the northwest African margin, representing a transect spanning 24° of latitude. Thirty calcareous nannofossil biohorizons were recognized in the Neogene and Quaternary sequences; only Site 661, located in water depths of 3500 m, contains a fossiliferous record older than the Oligocene. At Site 661, a 200-m-thick sequence of Upper Cretaceous sediments yielded Maestrichtian and uppermost Campanian nannofossils, yet a continuous Cretaceous/Tertiary boundary was not recovered. Widespread sediment slumps and turbidites deposited at many sites interrupted the pelagic sedimentation. A careful study of calcareous nannofossil and foraminifer assemblages correlated to paleomagnetic records suggests that "slumped" units at most sites were added as extra sediments to rapidly deposited pelagic sediments, with minor disturbance of the surrounding layers. Nannofossils are generally common to abundant and moderately preserved at all sites except for those located in two upwelling areas, where placoliths are etched and discoasters overgrown. Typical low-latitudinal zonal markers were used during this study, yet some of them were considered to be of little biostratigraphic value because of their inconsistent stratigraphic ranges and low abundances. This is especially apparent for the intervals representing the Miocene/Pliocene and Oligocene/Miocene boundaries. Characteristic nannofossils of cool-water conditions and low discoaster abundances occur at the coastal African upwelling and along the south equatorial divergence sites, signifying a stronger advection of cold waters toward the equator within the Canary and Benguela eastern boundary currents. Other/Unknown Material North Atlantic South Atlantic Ocean PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(-23.227500,-11.739200,21.331500,-1.390200) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
108-657A 108-658A 108-659A 108-660A 108-661A 108-662A 108-663A 108-664A 108-665A 108-666A 108-667A 108-668A Canarias Sea DRILL Drilling/drill rig Joides Resolution Leg108 North Atlantic Ocean Ocean Drilling Program ODP South Atlantic Ocean |
spellingShingle |
108-657A 108-658A 108-659A 108-660A 108-661A 108-662A 108-663A 108-664A 108-665A 108-666A 108-667A 108-668A Canarias Sea DRILL Drilling/drill rig Joides Resolution Leg108 North Atlantic Ocean Ocean Drilling Program ODP South Atlantic Ocean Manivit, Helene Calcareous nannofossil biostratigraphy of ODP Leg 108 sediments |
topic_facet |
108-657A 108-658A 108-659A 108-660A 108-661A 108-662A 108-663A 108-664A 108-665A 108-666A 108-667A 108-668A Canarias Sea DRILL Drilling/drill rig Joides Resolution Leg108 North Atlantic Ocean Ocean Drilling Program ODP South Atlantic Ocean |
description |
Calcareous nannofossils were examined from the 400 cores recovered at 12 sites during Ocean Drilling Program Leg 108 in the eastern equatorial Atlantic Ocean and along the northwest African margin, representing a transect spanning 24° of latitude. Thirty calcareous nannofossil biohorizons were recognized in the Neogene and Quaternary sequences; only Site 661, located in water depths of 3500 m, contains a fossiliferous record older than the Oligocene. At Site 661, a 200-m-thick sequence of Upper Cretaceous sediments yielded Maestrichtian and uppermost Campanian nannofossils, yet a continuous Cretaceous/Tertiary boundary was not recovered. Widespread sediment slumps and turbidites deposited at many sites interrupted the pelagic sedimentation. A careful study of calcareous nannofossil and foraminifer assemblages correlated to paleomagnetic records suggests that "slumped" units at most sites were added as extra sediments to rapidly deposited pelagic sediments, with minor disturbance of the surrounding layers. Nannofossils are generally common to abundant and moderately preserved at all sites except for those located in two upwelling areas, where placoliths are etched and discoasters overgrown. Typical low-latitudinal zonal markers were used during this study, yet some of them were considered to be of little biostratigraphic value because of their inconsistent stratigraphic ranges and low abundances. This is especially apparent for the intervals representing the Miocene/Pliocene and Oligocene/Miocene boundaries. Characteristic nannofossils of cool-water conditions and low discoaster abundances occur at the coastal African upwelling and along the south equatorial divergence sites, signifying a stronger advection of cold waters toward the equator within the Canary and Benguela eastern boundary currents. |
format |
Other/Unknown Material |
author |
Manivit, Helene |
author_facet |
Manivit, Helene |
author_sort |
Manivit, Helene |
title |
Calcareous nannofossil biostratigraphy of ODP Leg 108 sediments |
title_short |
Calcareous nannofossil biostratigraphy of ODP Leg 108 sediments |
title_full |
Calcareous nannofossil biostratigraphy of ODP Leg 108 sediments |
title_fullStr |
Calcareous nannofossil biostratigraphy of ODP Leg 108 sediments |
title_full_unstemmed |
Calcareous nannofossil biostratigraphy of ODP Leg 108 sediments |
title_sort |
calcareous nannofossil biostratigraphy of odp leg 108 sediments |
publisher |
PANGAEA |
publishDate |
1989 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.746289 https://doi.org/10.1594/PANGAEA.746289 |
op_coverage |
MEDIAN LATITUDE: 7.874669 * MEDIAN LONGITUDE: -19.084008 * SOUTH-BOUND LATITUDE: -1.390200 * WEST-BOUND LONGITUDE: -23.227500 * NORTH-BOUND LATITUDE: 21.331500 * EAST-BOUND LONGITUDE: -11.739200 * DATE/TIME START: 1986-02-27T22:15:00 * DATE/TIME END: 1986-04-14T11:30:00 |
long_lat |
ENVELOPE(-23.227500,-11.739200,21.331500,-1.390200) |
genre |
North Atlantic South Atlantic Ocean |
genre_facet |
North Atlantic South Atlantic Ocean |
op_source |
Supplement to: Manivit, Helene (1989): Calcareous nannofossil biostratigraphy of Leg 108 sediments. In: Ruddiman, W; Sarnthein, M; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 108, 35-69, https://doi.org/10.2973/odp.proc.sr.108.126.1989 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.746289 https://doi.org/10.1594/PANGAEA.746289 |
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.74628910.2973/odp.proc.sr.108.126.1989 |
_version_ |
1810464741132337152 |