Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Equatorial Pacific productivity changes near the Eocene-Oligocene boundary
Show others and affiliations
2014 (English)In: Paleoceanography, ISSN 0883-8305, E-ISSN 1944-9186, Vol. 29, no 9, 825-844 p.Article in journal (Refereed) Published
Abstract [en]

There is general agreement that productivity in high latitudes increased in the late Eocene and remained high in the early Oligocene. Evidence for both increased and decreased productivity across the Eocene-Oligocene transition (EOT) in the tropics has been presented, usually based on only one paleoproductivity proxy and often in sites with incomplete recovery of the EOT itself. A complete record of the Eocene-Oligocene transition was obtained at three drill sites in the eastern equatorial Pacific Ocean (ODP Site 1218 and IODP Sites U1333 and U1334). Four paleoproductivity proxies that have been examined at these sites, together with carbon and oxygen isotope measurements on early Oligocene planktonic foraminifera, give evidence of ecologic and oceanographic change across this climatically important boundary. Export productivity dropped sharply in the basal Oligocene (similar to 33.7Ma) and only recovered several hundred thousand years later; however, overall paleoproductivity in the early Oligocene never reached the average levels found in the late Eocene and in more modern times. Changes in the isotopic gradients between deep- and shallow-living planktonic foraminifera suggest a gradual shoaling of the thermocline through the early Oligocene that, on average, affected accumulation rates of barite, benthic foraminifera, and opal, as well as diatom abundance near 33.5Ma. An interval with abundant large diatoms beginning at 33.3Ma suggests an intermediate thermocline depth, which was followed by further shoaling, a dominance of smaller diatoms, and an increase in average primary productivity as estimated from accumulation rates of benthic foraminifera.

Place, publisher, year, edition, pages
2014. Vol. 29, no 9, 825-844 p.
Keyword [en]
paleoproductivity, Eocene-Oligocene, equatorial Pacific
National Category
Geology
Identifiers
URN: urn:nbn:se:su:diva-109988DOI: 10.1002/2014PA002656ISI: 000343875500001OAI: oai:DiVA.org:su-109988DiVA: diva2:768368
Note

AuthorCount:7;

Available from: 2014-12-03 Created: 2014-12-02 Last updated: 2017-12-05Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Coxall, Helen K.
By organisation
Department of Geological Sciences
In the same journal
Paleoceanography
Geology

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 40 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf