Late Eocene through Oligocene calcareous nannofossils from the paleo-equatorial Pacific Ocean – taxonomy, preservation history, biochronology and evolution

↓ Direkt till sidans innehåll
↓ Direkt till sidans sekundära innehåll (sidomenyn)

Search: onr:"swepub:oai:DiVA.org:su-27600" > Late Eocene through...

1 of 1
Previous record
Next record
To hitlist

Late Eocene through Oligocene calcareous nannofossils from the paleo-equatorial Pacific Ocean – taxonomy, preservation history, biochronology and evolution

Blaj, Teodora, 1979- (author): Stockholms universitet,Institutionen för geologi och geokemi,Marine Geosciences

Backman, Jan, Professor (thesis advisor): Stockholms universitet,Institutionen för geologi och geokemi

Henderiks, Jorijntje, Associate Professor (thesis advisor): Stockholms universitet,Institutionen för geologi och geokemi

Raffi, Isabella, Associate Professor (thesis advisor): Chieti University, Italy

Bown, Paul, Senior Lecturer (opponent): Department of Earth Sciences, University College London, UK

show less...

(creator_code:org_t)

ISBN 9789171558909
Stockholm : Department of Geology and Geochemistry, Stockholm University, 2009
English 26 s.
Series: Meddelanden från Stockholms universitets institution för geologi och geokemi, 1101-1599 ; 334

Related links:: https://su.diva-port... (primary) (Raw object); show more...; https://urn.kb.se/re...; show less...

Doctoral thesis (other academic/artistic)

Abstract Subject headings

This study aims to unravel the ecological and evolutionary dynamics within the calcareous nannofossil communities at the Eocene/Oligocene (E/O) transition and during the Oligocene time when Cenozoic 'icehouse' conditions were established. The main question this study aims to answer is whether the changes in the nannofossil assemblages were controlled by intrinsic evolutionary trends or if the changes were controlled by environmental factors such as changes in temperature and nutrient availability in the surface water. These questions are addressed with detailed analyses of the taxonomy, biostratigraphy and fluctuations in abundance and diversity of calcareous nannofossil assemblages from a continuous latest Eocene through Oligocene sediment section from the ODP Site 1218 (8°53.38´N, 135°22.00´W), paleo-equatorial Pacific Ocean. An improved nannofossil taxonomy and biostratigraphy has been established. At the E/O transition, changes in the nannofossil preservation mimics changes in calcium carbonate content. A detailed investigation of late Eocene and Oligocene sediments yields age estimates for ten nannofossil bioevents. Morphometric studies of the Reticulofenestra umbilicus-R. hillae show that these cannot be subdivided into two different morphospecies. Based on different morphometry and stratigraphic ranges, the Oligocene Sphenolithus lineage appears to be the result of a combined anagenetic and cladogenetic evolution. A new nannolith species is described: Triquetrorhabdulus longus. High-resolution nannofossil data indicate changes in the composition, abundance and diversity of the mid-Oligocene assemblages. Intervals of high diversity index coincide with Oi-glaciation events. However, visual examination of the variations in abundance of nannofossil taxa do not appear to correlate with changes in either oxygen or carbon isotopes. This presumably indicates that a dynamic equilibrium did not exist between these Oligocene nannoplankton assemblages and changes in surface water temperature or productivity conditions.

Subject headings

NATURVETENSKAP -- Geovetenskap och miljövetenskap -- Geologi (hsv//swe)
NATURAL SCIENCES -- Earth and Related Environmental Sciences -- Geology (hsv//eng)

Keyword

marine sediments
calcareous nannofossils
late Eocene
Oligocene
biochronology
evolution
morphometry
taxonomy
ODP Leg 199 Site 1218
paleo-equatorial Pacific Ocean
Historical geology and palaeontology
Historisk geologi och paleontologi
Marine Geoscience
marin geovetenskap

Publication and Content Type

vet (subject category)
dok (subject category)

Find in a library

Late Eocene through Oligocene calcareous nannofossils from the paleo-equatorial ... (Search the publication in LIBRIS)

To the university's database

1 of 1
Previous record
Next record
To hitlist

Find more in SwePub

By the author/editor: Blaj, Teodora, 1 ...; Backman, Jan, Pr ...; Henderiks, Jorij ...; Raffi, Isabella, ...; Bown, Paul, Seni ...

About the subject

NATURAL SCIENCES: NATURAL SCIENCES; and Earth and Relate ...; and Geology

Parts in the series: Meddelanden från ...

By the university: Stockholm University

Search outside SwePub

Extend your search to:: Google; Google Book Search; Google Scholar

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

LIBRIS.kb.se