Palaeobiogeography of Early Cretaceous (Berriasian-Barremian) calcareous nannoplankton
In order to assess Early Cretaceous nannoplankton biogeography, we studied a series of sites which provide a north-south transect across the Atlantic Ocean, supplemented by sections from the North Sea Basin, Barents Sea, Falkland Plateau, Weddell Sea (Antarctica), Argo Abyssal Plain (NW of Australia...
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ftucl:oai:eprints.ucl.ac.uk.OAI2:163838 2023-05-15T13:53:53+02:00 Palaeobiogeography of Early Cretaceous (Berriasian-Barremian) calcareous nannoplankton Street, C Bown, PR 2000-06 http://discovery.ucl.ac.uk/163838/ unknown ELSEVIER SCIENCE BV MARINE MICROPALEONTOLOGY , 39 (1-4) 265 - 291. (2000) calcareous nannofossils palaeobiogeography Early Cretaceous palaeoecology ATLANTIC-OCEAN NANNOFOSSILS SEA PALEOCEANOGRAPHY BIOSTRATIGRAPHY PRESERVATION BIOGEOGRAPHY DIVERSITY EVOLUTION SEDIMENTS Article 2000 ftucl 2016-10-20T22:18:22Z In order to assess Early Cretaceous nannoplankton biogeography, we studied a series of sites which provide a north-south transect across the Atlantic Ocean, supplemented by sections from the North Sea Basin, Barents Sea, Falkland Plateau, Weddell Sea (Antarctica), Argo Abyssal Plain (NW of Australia) and Neuquen Basin (Argentina). Quantitative assemblage data were gathered from each site for seven time-slices within the Berriasian to Barremian interval, each horizon being determined by a nannofossil datum. Trends in species relative abundance and measures of diversity, evenness and richness provide revealing biogeographic information. A broad, low- to mid-palaeolatitude zone (50 degrees N-50 degrees S) is flanked in both Northern and Southern Hemispheres by distinct high-palaeolatitude zones. Major changes in assemblage abundance and composition occur across a sharp biogeographic 'front' at around 50 degrees N and S palaeolatitude. High-palaeolatitude assemblages are lower in species richness and diversity and characterised by the presence of abundant, typically bipolar, taxa (e.g. Crucibiscutum salebrosum). A less distinct biogeographic boundary at similar to 40 degrees N is distinguished by the presence/absence of rarer, but biogeographically significant, taxa, many of which have previously been assigned to Boreal or Tethyan provinces. Continental shelf sites are characterised by lower-diversity assemblages with common to dominant diagnostic taxa, which vary with palaeolatitude: Nannoconus and Micrantholithus at low palaeolatitudes, and Biscutum constans and Zeugrhabdotus spp. at higher palaeolatitudes. The latter two taxa are considered to be indicative of elevated surface-water fertility and the former two may have been similarly adapted. The genus Watznoueria is ubiquitously dominant, giving the populations an unevenness, which appears to be a common feature throughout coccolithophore history. (C) 2000 Published by Elsevier Science B.V. All rights reserved. Article in Journal/Newspaper Antarc* Antarctica Barents Sea Weddell Sea University College London: UCL Discovery Argentina Barents Sea Falkland Plateau ENVELOPE(-50.000,-50.000,-51.000,-51.000) Weddell Weddell Sea |
institution |
Open Polar |
collection |
University College London: UCL Discovery |
op_collection_id |
ftucl |
language |
unknown |
topic |
calcareous nannofossils palaeobiogeography Early Cretaceous palaeoecology ATLANTIC-OCEAN NANNOFOSSILS SEA PALEOCEANOGRAPHY BIOSTRATIGRAPHY PRESERVATION BIOGEOGRAPHY DIVERSITY EVOLUTION SEDIMENTS |
spellingShingle |
calcareous nannofossils palaeobiogeography Early Cretaceous palaeoecology ATLANTIC-OCEAN NANNOFOSSILS SEA PALEOCEANOGRAPHY BIOSTRATIGRAPHY PRESERVATION BIOGEOGRAPHY DIVERSITY EVOLUTION SEDIMENTS Street, C Bown, PR Palaeobiogeography of Early Cretaceous (Berriasian-Barremian) calcareous nannoplankton |
topic_facet |
calcareous nannofossils palaeobiogeography Early Cretaceous palaeoecology ATLANTIC-OCEAN NANNOFOSSILS SEA PALEOCEANOGRAPHY BIOSTRATIGRAPHY PRESERVATION BIOGEOGRAPHY DIVERSITY EVOLUTION SEDIMENTS |
description |
In order to assess Early Cretaceous nannoplankton biogeography, we studied a series of sites which provide a north-south transect across the Atlantic Ocean, supplemented by sections from the North Sea Basin, Barents Sea, Falkland Plateau, Weddell Sea (Antarctica), Argo Abyssal Plain (NW of Australia) and Neuquen Basin (Argentina). Quantitative assemblage data were gathered from each site for seven time-slices within the Berriasian to Barremian interval, each horizon being determined by a nannofossil datum. Trends in species relative abundance and measures of diversity, evenness and richness provide revealing biogeographic information. A broad, low- to mid-palaeolatitude zone (50 degrees N-50 degrees S) is flanked in both Northern and Southern Hemispheres by distinct high-palaeolatitude zones. Major changes in assemblage abundance and composition occur across a sharp biogeographic 'front' at around 50 degrees N and S palaeolatitude. High-palaeolatitude assemblages are lower in species richness and diversity and characterised by the presence of abundant, typically bipolar, taxa (e.g. Crucibiscutum salebrosum). A less distinct biogeographic boundary at similar to 40 degrees N is distinguished by the presence/absence of rarer, but biogeographically significant, taxa, many of which have previously been assigned to Boreal or Tethyan provinces. Continental shelf sites are characterised by lower-diversity assemblages with common to dominant diagnostic taxa, which vary with palaeolatitude: Nannoconus and Micrantholithus at low palaeolatitudes, and Biscutum constans and Zeugrhabdotus spp. at higher palaeolatitudes. The latter two taxa are considered to be indicative of elevated surface-water fertility and the former two may have been similarly adapted. The genus Watznoueria is ubiquitously dominant, giving the populations an unevenness, which appears to be a common feature throughout coccolithophore history. (C) 2000 Published by Elsevier Science B.V. All rights reserved. |
format |
Article in Journal/Newspaper |
author |
Street, C Bown, PR |
author_facet |
Street, C Bown, PR |
author_sort |
Street, C |
title |
Palaeobiogeography of Early Cretaceous (Berriasian-Barremian) calcareous nannoplankton |
title_short |
Palaeobiogeography of Early Cretaceous (Berriasian-Barremian) calcareous nannoplankton |
title_full |
Palaeobiogeography of Early Cretaceous (Berriasian-Barremian) calcareous nannoplankton |
title_fullStr |
Palaeobiogeography of Early Cretaceous (Berriasian-Barremian) calcareous nannoplankton |
title_full_unstemmed |
Palaeobiogeography of Early Cretaceous (Berriasian-Barremian) calcareous nannoplankton |
title_sort |
palaeobiogeography of early cretaceous (berriasian-barremian) calcareous nannoplankton |
publisher |
ELSEVIER SCIENCE BV |
publishDate |
2000 |
url |
http://discovery.ucl.ac.uk/163838/ |
long_lat |
ENVELOPE(-50.000,-50.000,-51.000,-51.000) |
geographic |
Argentina Barents Sea Falkland Plateau Weddell Weddell Sea |
geographic_facet |
Argentina Barents Sea Falkland Plateau Weddell Weddell Sea |
genre |
Antarc* Antarctica Barents Sea Weddell Sea |
genre_facet |
Antarc* Antarctica Barents Sea Weddell Sea |
op_source |
MARINE MICROPALEONTOLOGY , 39 (1-4) 265 - 291. (2000) |
_version_ |
1766259364914528256 |