Pleistocene glaciations of northern Russia – a modern view

Abstract

The size, age and dynamics of Pleistocene glaciers, especially ice sheets that periodically covered the northern seaboard of Eurasia, are crucial for understanding the evolution of arctic climates, sea-level changes, the biota and tectonism. General ideas on the glacial history of the vast areas of northern Russia between 48°and 148°E, beyond the limits of the Fennoscandian glaciation, have considerably changed during the last two decades. The change towards modern views may even be considered as a paradigm shift from the conventional wisdom of the previous half-century. The transformation of the main landmarks of late Quaternary glacial history started in the 1970s and accelerated after 1993 as a result of international collaboration in the Russian Arctic. A wealth of new sedimentological, geomorphic and stratigraphic data has recently accumulated for the sedimentary record of the last 200 ka. This information, together with data collected from native geological surveys, has been synthesized in the form of digital maps of ice limits based on key stratigraphic sites. The results have been published as contributions to the international programs QUEEN and APEX and also as parts of global compilations. These publications give general overviews of the Eurasian glacial history, but some important modern data are reported only in the Russian literature and therefore are hardly known to the international community. In this paper I will first consider the background material on the non-Scandinavian glaciations and then follow this with a review of the modern results obtained in the course of international cooperation. The outcome is inevitably influenced (or biased) by my long-term experience in studying the Pleistocene of northern Russia. I will not discuss here the extreme northeast of Siberia (western Beringia), as this is a distinct topic partly overviewed in recent publications.

The Taimyr Peninsula and the Severnaya Zemlya archipelago, Arctic Russia: a synthesis of glacial history and palaeo-environmental change during the Last Glacial cycle (MIS 5e–2)

“…These reveal thick diamicts (glacials/stadials) interbedded with fluvial/organic beds (interglacials/interstadials), the latter often replaced with marine sediment in the arctic part of west Siberia (see review in, e.g. Astakhov, 2013). The same nomenclature has been used for the stratigraphic work on the Taimyr Peninsula, as in the reference work Antropogen Taimyra by Kind and Leonov (1982).…”

“…However, a large number of modern radiocarbon datings on molluscs within what by Kind and Leonov (1982) was classified as Karginsky marine sediments on southern Taimyr all give infinite ages, while OSL and ESR ages suggest Early Zyryanka or classic Kazantsevo ages (M€ oller, unpublished). Recent redating of the Karginsky type locality along the Yesinei River (Astakhov and Nazarov, 2010;Astakhov, 2013) gave infinite radiocarbon ages, whereas OSL dating of sediment gave a clustered age group with a mean age of 111 ka and an ESR age of c. 122 ka, which all suggest a better correlation to the European Eemian/MIS 5e of this site. These recent improvements in methods Kind and Leonov (1982), but drawn from Landsat image interpretation by M€ oller and Sallaba (2010) Alexanderson et al (2001).…”

“…As pointed out in more recent research (e.g. Svendsen et al, 2004;Astakhov and Nazarov, 2010;Astakhov, 2013;Alexanderson et al, 2014), this stratigraphic/chronological framework has two main pit-falls. Deposits defined as Kazantsevo beds in NW Siberia hosts at places the extinct bivalve Cyrtodaria angusta.…”

“…Basic map is from the International Bathymetric Chart of the Arctic Ocean (IBCAO) (Jakobsson et al, 2008a). and techniques have led Astakhov (2013) to revise the whole stratigraphic/chronologic scheme of NW Siberia (Table 1); it is thus suggested that the Last Interglacial should be named Karginsky and correlated with the European Eemian (MIS 5e), whereas the former Kazantsevo interglacial of NW Siberia should be considered Middle Pleistocene (MIS 7) in age. This chronostratigraphic subdivision (revised scheme for west Siberia, Table 1) is accordingly used throughout in this paper.…”

“…All are, however, poorly constrained to their age of formation; numerous suggestions have been put forward for which glacial stages and phases individual ridges represent, varying from all being of Taz (MIS 6) glaciation age (Fisher et al, 1990) to the southernmost being of Early Zyryanka age (the Urdachsk and Sampesa IMZ, Fig. 1), whereas the more northern JangodaeSyntabuleSeverokokorsk (JSK) and the MokorittoeUpper Table 1 Classic subdivision of the Late and upper part of the Middle Pleistocene of West Siberia according to Volkova and Babushkin (2000) 4 , and the revised chronostratigraphy of Astakhov (2013) 5 , used in this paper. Ages are according to Gibbard et al (2010) 1 , Aitken and Stokes (1997) TaimyreBaikuronyora ridge systems, being very complex to their formation, are suggested having elements of both Early and Late Zyryanka age (Andreeva, 1978;Andreeva and Isaeva, 1982;Kind and Leonov, 1982;Isayeva, 1984;Siegert et al, 1999).…”