Pleistocene and Holocene in Murchisonforden area, Nordaustlandet, Svalbard.

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• Professor Veli-Pekka Salonen, Dept. of Geosciences and Geography, University of Helsinki (and Visiting fellow at Clare Hall)
• Wednesday 21 March 2012, 13:00-13:45
• Scott Polar Research Institute, main lecture theatre.

If you have a question about this talk, please contact Steven Palmer.

The research campaign formed part of International Polar Year (2007-2009) activities (IPY-Kinnvika), which made it possible to run three expeditions to High Arctic terrains of Northaustlandet (Svalbard). These areas normally have very difficult access. The target was to reconstruct the glacier history of the Barents Ice Sheet within its north-westernmost sector which has thusfar been only little studied. The area is important palaeoclimatologically because influenced by relatively warm North Atlantic waters, and because the reactions of the glaciers to climate fluctuations are known to be fast and extreme.

Sediments from entire Weichselian glacial Stage were located and related with other similar records from all around Spitsbergen (Kaakinen et al. 2008). The Weichselian record found represented three stadials and two interstadials. The Mid-Weichselian stadial ca. 60-50 000 BP affected the area most heavily causing areal scouring of the landscape and depositing tills. During the latest glacial phase, 25000 – 15000 BP, frozen bed conditions prevailed leading to an almost non-existing erosion or deposition of strata. Deglaciation was dated to ca. 12 500 years ago.

Holocene foraminiferal assemblages from Isvika bay sediments indicate a transition from glacier-proximal to glacier-distal faunas with a clear indication of the inflow of warmer North Atlantic waters in the early Holocene (Kubischta et al. 2011). The climatic optimum was terminated by a glacier re-advance that occurred 6000 years ago. This event caused the deposition of waterlain till, that disturbed the glacio-isostatic emerging of the shores and changed local chironomid fauna to indicate generally colder lake temperatures (Luoto et al. 2011). Since the Mid-Holocene, foraminifera and ice rafted detritus (IRD-) record indicate a gradual cooling climatic trend. Lacustrine faunal changes testify to major environmental turnovers, including a total decline of a previously unknown endemic cladocera species (Nevalainen et al. 2011).

References Kaakinen, A., Salonen, V.P., Kubischta, A., Eskola, K.O. ja Oinonen, M. 2009. Weichselian glacial stage in Murchisonfjorden, Nordaustlandet, Svalbard. Boreas 38:718-729. Kubischta, F., Knudsen, K.L., Ojala, A. ja Salonen, V-P. 2011. Holocene benthic foraminiferal record from a high-arctic fjord, Nordaustlandet, Svalbard. Geographiska Annaler 93, 227-242. Luoto, T.P., Nevalainen, L., Kubischta, F., Kultti, S., Knudsen, K.L., ja Salonen, V-P. 2011. Late Quaternary ecological turnover in a High Arctic Lake Einstaken, Nordaustlandet, Svalbard (80 °N). Geographiska Annaler, 93, 337-354. Nevalainen, L., Van Damme, K., Luoto. T.P. ja Salonen, V-P. 2011.- Fossil remains of an unknown Alona species (Chydoridae, Aloninae) from a high arctic lake in Nordaustlandet, Svalbard, and its relation to glaciation and Holocene environmental history. Polar Biology, 35, 325–333.

This talk is part of the Scott Polar Research Institute - Polar Physical Sciences Seminar series.

This talk is included in these lists:

• AUB_Cambridge Seminars
• Climate Science Seminars within Cambridge
• Department of Geography
• Scott Polar Research Institute - Polar Physical Sciences Seminar
• Scott Polar Research Institute, main lecture theatre
• seminars

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