Climate Change in the Southern Ocean During the Middle Eocene to Early Oligocene: A Palynological Perspective
The Antarctic and Southern Ocean is an area that was greatly affected by climatic changes during the Middle Eocene to Early Oligocene (E/O). This study aims to document climate-induced changes of the marine palynomorphs (mostly dinoflagellate cysts) by developing a Circum-Antarctic biozonation, and...
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Victoria University of Wellington
2013
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ftvuwellington:oai:researcharchive.vuw.ac.nz:10063/2696 2023-08-15T12:38:02+02:00 Climate Change in the Southern Ocean During the Middle Eocene to Early Oligocene: A Palynological Perspective Storkey, Claire Andrea Hannah, Mike 2013 http://researcharchive.vuw.ac.nz/handle/10063/2696 en_NZ eng Victoria University of Wellington http://researcharchive.vuw.ac.nz/handle/10063/2696 Dinocysts Eocene/ Oligocene Southern Ocean Text Doctoral 2013 ftvuwellington 2023-07-25T17:23:47Z The Antarctic and Southern Ocean is an area that was greatly affected by climatic changes during the Middle Eocene to Early Oligocene (E/O). This study aims to document climate-induced changes of the marine palynomorphs (mostly dinoflagellate cysts) by developing a Circum-Antarctic biozonation, and establishing the distribution and effects of cooling on the palynomorph assemblages and the palaeoenvironment. Samples were obtained from four sites by the Ocean Drilling Program (ODP) and Deep Sea Drilling Project (DSDP) and the palynological content was analyzed. These sites were selected as they may record effects of circulation changes and cooling trends, reflecting climate changes. ODP site 696B, was inner neritic and located in the South Orkney microcontinent, Weddell Sea. The other three sites were pelagic with ODP 699A located on the Northeast Georgia Rise, Falklands, ODP 748B located in the Western part of the Raggart Basin, Kerguelen Plateau and DSDP 277 located in Cathedral Depression on the Southern Campbell Plateau. From this analysis a comprehensive record of the local climatic transitions was ascertained, utilising assemblages of fossil organic-walled dinoflagellate cysts (dinocysts), acritarchs, prasinophyte algae, microforaminiferal linings, scoledonts and terrestrial material. The establishment of a standard nannofossil biostratigraphy provided a temporal framework of the marine palynomorphs in each site. Key dinocyst datums recognised as first or last occurrences that correlated reliably between sites, were compared with the nannofossil zones of each site. The purpose was to provide a Middle Eocene/Early Oligocene dinocyst biostratigraphy that temporally constrains the assemblages. Six primary datums and two secondary datums resulted, which lead to the recognition of four biozones and established a new biozonation in the Southern Ocean. The zones identified various dinocyst events, giving an indication of their probable palaeoenvironments. The Circum-Antarctic distribution pattern of palynomorph ... Doctoral or Postdoctoral Thesis Antarc* Antarctic Southern Ocean Weddell Sea Victoria University of Wellington: ResearchArchive Antarctic Campbell Plateau ENVELOPE(171.000,171.000,-50.667,-50.667) Georgia Rise ENVELOPE(-32.500,-32.500,-52.500,-52.500) Kerguelen Northeast Georgia Rise ENVELOPE(-32.500,-32.500,-52.500,-52.500) Southern Ocean The Antarctic Weddell Weddell Sea |
institution |
Open Polar |
collection |
Victoria University of Wellington: ResearchArchive |
op_collection_id |
ftvuwellington |
language |
English |
topic |
Dinocysts Eocene/ Oligocene Southern Ocean |
spellingShingle |
Dinocysts Eocene/ Oligocene Southern Ocean Storkey, Claire Andrea Climate Change in the Southern Ocean During the Middle Eocene to Early Oligocene: A Palynological Perspective |
topic_facet |
Dinocysts Eocene/ Oligocene Southern Ocean |
description |
The Antarctic and Southern Ocean is an area that was greatly affected by climatic changes during the Middle Eocene to Early Oligocene (E/O). This study aims to document climate-induced changes of the marine palynomorphs (mostly dinoflagellate cysts) by developing a Circum-Antarctic biozonation, and establishing the distribution and effects of cooling on the palynomorph assemblages and the palaeoenvironment. Samples were obtained from four sites by the Ocean Drilling Program (ODP) and Deep Sea Drilling Project (DSDP) and the palynological content was analyzed. These sites were selected as they may record effects of circulation changes and cooling trends, reflecting climate changes. ODP site 696B, was inner neritic and located in the South Orkney microcontinent, Weddell Sea. The other three sites were pelagic with ODP 699A located on the Northeast Georgia Rise, Falklands, ODP 748B located in the Western part of the Raggart Basin, Kerguelen Plateau and DSDP 277 located in Cathedral Depression on the Southern Campbell Plateau. From this analysis a comprehensive record of the local climatic transitions was ascertained, utilising assemblages of fossil organic-walled dinoflagellate cysts (dinocysts), acritarchs, prasinophyte algae, microforaminiferal linings, scoledonts and terrestrial material. The establishment of a standard nannofossil biostratigraphy provided a temporal framework of the marine palynomorphs in each site. Key dinocyst datums recognised as first or last occurrences that correlated reliably between sites, were compared with the nannofossil zones of each site. The purpose was to provide a Middle Eocene/Early Oligocene dinocyst biostratigraphy that temporally constrains the assemblages. Six primary datums and two secondary datums resulted, which lead to the recognition of four biozones and established a new biozonation in the Southern Ocean. The zones identified various dinocyst events, giving an indication of their probable palaeoenvironments. The Circum-Antarctic distribution pattern of palynomorph ... |
author2 |
Hannah, Mike |
format |
Doctoral or Postdoctoral Thesis |
author |
Storkey, Claire Andrea |
author_facet |
Storkey, Claire Andrea |
author_sort |
Storkey, Claire Andrea |
title |
Climate Change in the Southern Ocean During the Middle Eocene to Early Oligocene: A Palynological Perspective |
title_short |
Climate Change in the Southern Ocean During the Middle Eocene to Early Oligocene: A Palynological Perspective |
title_full |
Climate Change in the Southern Ocean During the Middle Eocene to Early Oligocene: A Palynological Perspective |
title_fullStr |
Climate Change in the Southern Ocean During the Middle Eocene to Early Oligocene: A Palynological Perspective |
title_full_unstemmed |
Climate Change in the Southern Ocean During the Middle Eocene to Early Oligocene: A Palynological Perspective |
title_sort |
climate change in the southern ocean during the middle eocene to early oligocene: a palynological perspective |
publisher |
Victoria University of Wellington |
publishDate |
2013 |
url |
http://researcharchive.vuw.ac.nz/handle/10063/2696 |
long_lat |
ENVELOPE(171.000,171.000,-50.667,-50.667) ENVELOPE(-32.500,-32.500,-52.500,-52.500) ENVELOPE(-32.500,-32.500,-52.500,-52.500) |
geographic |
Antarctic Campbell Plateau Georgia Rise Kerguelen Northeast Georgia Rise Southern Ocean The Antarctic Weddell Weddell Sea |
geographic_facet |
Antarctic Campbell Plateau Georgia Rise Kerguelen Northeast Georgia Rise Southern Ocean The Antarctic Weddell Weddell Sea |
genre |
Antarc* Antarctic Southern Ocean Weddell Sea |
genre_facet |
Antarc* Antarctic Southern Ocean Weddell Sea |
op_relation |
http://researcharchive.vuw.ac.nz/handle/10063/2696 |
_version_ |
1774297946415693824 |