Late Quaternary Biostratigraphy and Paleoceanography of the central Arctic Ocean
The central Arctic Ocean is one of the least explored deep sea regions and long biostratigraphic sediment records are sparse. The main focus of this thesis is the Arctic Ocean foraminiferal record and its application to reconstruct paleoceanographic variations and summer sea ice cover changes betwee...
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Institutionen för geologiska vetenskaper
2011
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ftstockholmuniv:oai:DiVA.org:su-57245 2023-05-15T14:46:10+02:00 Late Quaternary Biostratigraphy and Paleoceanography of the central Arctic Ocean Hanslik, Daniela 2011 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-57245 eng eng Institutionen för geologiska vetenskaper Stockholm : Department of Geological Sciences, Stockholm University Meddelanden från Stockholms universitets institution för geologiska vetenskaper 345 http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-57245 urn:isbn:978-91-7447-311-7 info:eu-repo/semantics/openAccess Arctic Ocean Quaternary biostratigraphy foraminifera paleoceanography Other Earth and Related Environmental Sciences Annan geovetenskap och miljövetenskap Doctoral thesis, comprehensive summary info:eu-repo/semantics/doctoralThesis text 2011 ftstockholmuniv 2023-02-23T21:42:04Z The central Arctic Ocean is one of the least explored deep sea regions and long biostratigraphic sediment records are sparse. The main focus of this thesis is the Arctic Ocean foraminiferal record and its application to reconstruct paleoceanographic variations and summer sea ice cover changes between late Quaternary interglacial periods. One of the studied cores was retrieved from the central Lomonosov Ridge Intra Basin. This core contains a relatively high-resolution biostratigraphic record spanning Marine Isotope Stages (MIS) 1–3, although with a hiatus encompassing the Last Glacial Maximum. Radiocarbon age calibrations in this core show a decreasing trend of high marine reservoir ages of about 1400 years during the last deglaciation to 700 years in the late Holocene. The cores from the Lomonosov Ridge off Greenland and the Morris Jesup Rise contain preserved calcareous microfossils further back in time than most previously studied central Arctic Ocean cores. The calcium content estimated by X-ray fluorescence scanning of these cores shows a distinct pattern of calcium rich intervals coinciding with peaks in foraminiferal abundance in the sediment record of MIS 1–7. The calcium peaks originate from material accumulated during interglacials, primarily through detrital carbonate and dolomite input from the decaying North American ice sheet and secondarily from biogenic material. Intervals of calcareous benthic foraminifera are found in pre MIS 7 sediments on both the southern Lomonosov Ridge and Morris Jesup Rise. Their assemblage composition and stable carbon isotope data suggest increased primary production and decreased summer sea ice cover compared to the Holocene central Arctic Ocean. This is also suggested for an interval of high abundance of the subpolar planktic foraminifera Turborotalita quinqueloba on the southern Lomonosov Ridge with a proposed MIS 11 age. At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 3: Submitted. Doctoral or Postdoctoral Thesis Arctic Arctic Ocean Foraminifera* Greenland Ice Sheet Lomonosov Ridge Sea ice Stockholm University: Publications (DiVA) Arctic Arctic Ocean Greenland Morris Jesup Rise ENVELOPE(-20.000,-20.000,83.750,83.750) |
institution |
Open Polar |
collection |
Stockholm University: Publications (DiVA) |
op_collection_id |
ftstockholmuniv |
language |
English |
topic |
Arctic Ocean Quaternary biostratigraphy foraminifera paleoceanography Other Earth and Related Environmental Sciences Annan geovetenskap och miljövetenskap |
spellingShingle |
Arctic Ocean Quaternary biostratigraphy foraminifera paleoceanography Other Earth and Related Environmental Sciences Annan geovetenskap och miljövetenskap Hanslik, Daniela Late Quaternary Biostratigraphy and Paleoceanography of the central Arctic Ocean |
topic_facet |
Arctic Ocean Quaternary biostratigraphy foraminifera paleoceanography Other Earth and Related Environmental Sciences Annan geovetenskap och miljövetenskap |
description |
The central Arctic Ocean is one of the least explored deep sea regions and long biostratigraphic sediment records are sparse. The main focus of this thesis is the Arctic Ocean foraminiferal record and its application to reconstruct paleoceanographic variations and summer sea ice cover changes between late Quaternary interglacial periods. One of the studied cores was retrieved from the central Lomonosov Ridge Intra Basin. This core contains a relatively high-resolution biostratigraphic record spanning Marine Isotope Stages (MIS) 1–3, although with a hiatus encompassing the Last Glacial Maximum. Radiocarbon age calibrations in this core show a decreasing trend of high marine reservoir ages of about 1400 years during the last deglaciation to 700 years in the late Holocene. The cores from the Lomonosov Ridge off Greenland and the Morris Jesup Rise contain preserved calcareous microfossils further back in time than most previously studied central Arctic Ocean cores. The calcium content estimated by X-ray fluorescence scanning of these cores shows a distinct pattern of calcium rich intervals coinciding with peaks in foraminiferal abundance in the sediment record of MIS 1–7. The calcium peaks originate from material accumulated during interglacials, primarily through detrital carbonate and dolomite input from the decaying North American ice sheet and secondarily from biogenic material. Intervals of calcareous benthic foraminifera are found in pre MIS 7 sediments on both the southern Lomonosov Ridge and Morris Jesup Rise. Their assemblage composition and stable carbon isotope data suggest increased primary production and decreased summer sea ice cover compared to the Holocene central Arctic Ocean. This is also suggested for an interval of high abundance of the subpolar planktic foraminifera Turborotalita quinqueloba on the southern Lomonosov Ridge with a proposed MIS 11 age. At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 3: Submitted. |
format |
Doctoral or Postdoctoral Thesis |
author |
Hanslik, Daniela |
author_facet |
Hanslik, Daniela |
author_sort |
Hanslik, Daniela |
title |
Late Quaternary Biostratigraphy and Paleoceanography of the central Arctic Ocean |
title_short |
Late Quaternary Biostratigraphy and Paleoceanography of the central Arctic Ocean |
title_full |
Late Quaternary Biostratigraphy and Paleoceanography of the central Arctic Ocean |
title_fullStr |
Late Quaternary Biostratigraphy and Paleoceanography of the central Arctic Ocean |
title_full_unstemmed |
Late Quaternary Biostratigraphy and Paleoceanography of the central Arctic Ocean |
title_sort |
late quaternary biostratigraphy and paleoceanography of the central arctic ocean |
publisher |
Institutionen för geologiska vetenskaper |
publishDate |
2011 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-57245 |
long_lat |
ENVELOPE(-20.000,-20.000,83.750,83.750) |
geographic |
Arctic Arctic Ocean Greenland Morris Jesup Rise |
geographic_facet |
Arctic Arctic Ocean Greenland Morris Jesup Rise |
genre |
Arctic Arctic Ocean Foraminifera* Greenland Ice Sheet Lomonosov Ridge Sea ice |
genre_facet |
Arctic Arctic Ocean Foraminifera* Greenland Ice Sheet Lomonosov Ridge Sea ice |
op_relation |
Meddelanden från Stockholms universitets institution för geologiska vetenskaper 345 http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-57245 urn:isbn:978-91-7447-311-7 |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1766317417056698368 |