Middle Miocene environmental change in the eastern Atlantic Ocean at the Porcupine Basin (IODP Leg 307) : results from an integrated palynological and biogeochemical study
The relatively warm climate of the Miocene reached peak values during the middle Miocene Climatic Optimum (MMCO; 17-14.5 Ma). After the MMCO, the global climate started cooling. This happened through several short-lived cooling events, represented by positive oxygen isotope excursions: the Mi-events...
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ftunivgent:oai:archive.ugent.be:4414521 2023-06-11T04:05:24+02:00 Middle Miocene environmental change in the eastern Atlantic Ocean at the Porcupine Basin (IODP Leg 307) : results from an integrated palynological and biogeochemical study Quaijtaal, Willemijn Schouten, Stefan Donders, Timme Louwye, Stephen 2012 https://biblio.ugent.be/publication/4414521 http://hdl.handle.net/1854/LU-4414521 eng eng Australian Geosciences Council https://biblio.ugent.be/publication/4414521 http://hdl.handle.net/1854/LU-4414521 Proceedings of the 34th International Geological Congress 2012 ISBN: 9780646578002 Earth and Environmental Sciences conference info:eu-repo/semantics/conferenceObject info:eu-repo/semantics/publishedVersion 2012 ftunivgent 2023-05-10T22:32:33Z The relatively warm climate of the Miocene reached peak values during the middle Miocene Climatic Optimum (MMCO; 17-14.5 Ma). After the MMCO, the global climate started cooling. This happened through several short-lived cooling events, represented by positive oxygen isotope excursions: the Mi-events. These disturbances can be associated with growth of the East Antarctic Ice Sheet and potentially Northern Hemisphere ice expansion. The causes and consequences of the Mi-events are not well constrained. For this reason we want to examine the role of the Gulf Stream in the cooling and subsequent warming of the Mi-events, since it is a possible mechanism to amplify regional changes in northwestern Europe. Integrated Ocean Drilling Program (IODP) Leg 307 recovered a high resolution record from the middle Miocene of the Porcupine Basin, offshore southwestern Ireland and therefore under the influence of the Gulf Stream. We have extracted well-preserved palynomorphs (mainly organic-walled dinoflagellate cysts, acritarchs, some pollen) and organic molecules for paleothermometry (e.g. TEX86 and UK'37) from core 1318B. With these proxies the development of the Mi-3 and Mi-4 events are reconstructed on high resolution, by assessing e.g. temperature, sea level, thermocline depth and productivity. First results indicate a pronounced cooling as recorded simultaneously in TEX86, Uk'37 and dinoflagellate cyst assemblages during Mi-4. The presented results will focus in detail on the phasing and rates of change in the reconstructed Mi-events. Conference Object Antarc* Antarctic Ice Sheet Ghent University Academic Bibliography Antarctic East Antarctic Ice Sheet |
institution |
Open Polar |
collection |
Ghent University Academic Bibliography |
op_collection_id |
ftunivgent |
language |
English |
topic |
Earth and Environmental Sciences |
spellingShingle |
Earth and Environmental Sciences Quaijtaal, Willemijn Schouten, Stefan Donders, Timme Louwye, Stephen Middle Miocene environmental change in the eastern Atlantic Ocean at the Porcupine Basin (IODP Leg 307) : results from an integrated palynological and biogeochemical study |
topic_facet |
Earth and Environmental Sciences |
description |
The relatively warm climate of the Miocene reached peak values during the middle Miocene Climatic Optimum (MMCO; 17-14.5 Ma). After the MMCO, the global climate started cooling. This happened through several short-lived cooling events, represented by positive oxygen isotope excursions: the Mi-events. These disturbances can be associated with growth of the East Antarctic Ice Sheet and potentially Northern Hemisphere ice expansion. The causes and consequences of the Mi-events are not well constrained. For this reason we want to examine the role of the Gulf Stream in the cooling and subsequent warming of the Mi-events, since it is a possible mechanism to amplify regional changes in northwestern Europe. Integrated Ocean Drilling Program (IODP) Leg 307 recovered a high resolution record from the middle Miocene of the Porcupine Basin, offshore southwestern Ireland and therefore under the influence of the Gulf Stream. We have extracted well-preserved palynomorphs (mainly organic-walled dinoflagellate cysts, acritarchs, some pollen) and organic molecules for paleothermometry (e.g. TEX86 and UK'37) from core 1318B. With these proxies the development of the Mi-3 and Mi-4 events are reconstructed on high resolution, by assessing e.g. temperature, sea level, thermocline depth and productivity. First results indicate a pronounced cooling as recorded simultaneously in TEX86, Uk'37 and dinoflagellate cyst assemblages during Mi-4. The presented results will focus in detail on the phasing and rates of change in the reconstructed Mi-events. |
format |
Conference Object |
author |
Quaijtaal, Willemijn Schouten, Stefan Donders, Timme Louwye, Stephen |
author_facet |
Quaijtaal, Willemijn Schouten, Stefan Donders, Timme Louwye, Stephen |
author_sort |
Quaijtaal, Willemijn |
title |
Middle Miocene environmental change in the eastern Atlantic Ocean at the Porcupine Basin (IODP Leg 307) : results from an integrated palynological and biogeochemical study |
title_short |
Middle Miocene environmental change in the eastern Atlantic Ocean at the Porcupine Basin (IODP Leg 307) : results from an integrated palynological and biogeochemical study |
title_full |
Middle Miocene environmental change in the eastern Atlantic Ocean at the Porcupine Basin (IODP Leg 307) : results from an integrated palynological and biogeochemical study |
title_fullStr |
Middle Miocene environmental change in the eastern Atlantic Ocean at the Porcupine Basin (IODP Leg 307) : results from an integrated palynological and biogeochemical study |
title_full_unstemmed |
Middle Miocene environmental change in the eastern Atlantic Ocean at the Porcupine Basin (IODP Leg 307) : results from an integrated palynological and biogeochemical study |
title_sort |
middle miocene environmental change in the eastern atlantic ocean at the porcupine basin (iodp leg 307) : results from an integrated palynological and biogeochemical study |
publisher |
Australian Geosciences Council |
publishDate |
2012 |
url |
https://biblio.ugent.be/publication/4414521 http://hdl.handle.net/1854/LU-4414521 |
geographic |
Antarctic East Antarctic Ice Sheet |
geographic_facet |
Antarctic East Antarctic Ice Sheet |
genre |
Antarc* Antarctic Ice Sheet |
genre_facet |
Antarc* Antarctic Ice Sheet |
op_source |
Proceedings of the 34th International Geological Congress 2012 ISBN: 9780646578002 |
op_relation |
https://biblio.ugent.be/publication/4414521 http://hdl.handle.net/1854/LU-4414521 |
_version_ |
1768375161501777920 |