Severnaya Zemlya, arctic Russia: a nucleation area for Kara Sea ice sheets during the Middle to Late Quaternary

Quaternary glacial stratigraphy and relative sea-level changes reveal at least four expansions of the Kara Sea ice sheet over the Severnaya Zemlya Archipelago at 79°N in the Russian Arctic, as indicated from tills interbedded with marine sediments, exposed in stratigraphic superposition, and from ra...

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Bibliographic Details
Main Authors: Möller, Per, Lubinski, David J., Ingólfsson, Ólafur, Forman, Steven L., Seidenkrantz, Marit-Solveig, Bolshiyanov, Dimitry Yu., Lokrantz, Hanna, Antonov, Oleg, Pavlov, Maxim, Ljung, Karl, Zeeberg, JaapJan, Andreev, Andrei
Format: Article in Journal/Newspaper
Language:English
Published: 2006
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Online Access:https://pure.au.dk/portal/da/publications/severnaya-zemlya-arctic-russia-a-nucleation-area-for-kara-sea-ice-sheets-during-the-middle-to-late-quaternary(246a3420-b1f7-11db-bee9-02004c4f4f50).html
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Summary:Quaternary glacial stratigraphy and relative sea-level changes reveal at least four expansions of the Kara Sea ice sheet over the Severnaya Zemlya Archipelago at 79°N in the Russian Arctic, as indicated from tills interbedded with marine sediments, exposed in stratigraphic superposition, and from raised-beach sequences that occur at altitudes up to 140 m a.s.l. Chronologic control is provided by AMS 14 C, electron-spin resonance, green-stimulated luminescence, and aspartic-acid geochronology. Major glaciations followed by deglaciation and marine inundation occurred during MIS 10-9, MIS 8-7, MIS 6-5e and MIS 5d-3. The MIS 6-5e event, associated with the high marine limit, implies ice-sheet thickness of >2000 m only 200 km from the deep Arctic Ocean, consistent with published evidence of ice grounding at ~1000 m water depth in the central Arctic Ocean. Till fabrics and glacial tectonics record repeated expansions of local ice caps exclusively, suggesting wet-based ice cap advance followed by cold-based regional ice-sheet expansion. Local ice caps over highland sites along the perimeter of the shallow Kara Sea, including the Byrranga Mountains, appear to have repeatedly fostered initiation of a large Kara Sea ice sheet, with exception of the Last Glacial Maximum (MIS 2), when Kara Sea ice did not impact Severnaya Zemlya and barely graced northernmost Taymyr Peninsula.