In northern Russia ice sheets centred on Scandinavia and in the Barents- and Kara Seas fought to occupy the northern rim of the continent during the last ice age, the Weichselian of western Europe or the Valdaian of Russia. Today, the imprint left by these different ice sheets tells a story about dramatic climate changes and facilitates a better understanding of the mechanisms and forces driving the present-day climate system. Since 1995 a European research project, QUEEN (Quaternary Environment of the Eurasian North) has attempted to reconstruct the changing environments of northern Eurasia from the last interglacial (the Eemian of western Europe or Mikulinian of Russia) and through the Weichselian—what were the processes behind the growth and decay of the ice sheets, what was the duration of individual ice advances, and what was their relationship to the north Atlantic oceanography?

The QUEEN Project comprises more than 70 Scientists from eight nations and critical areas for field-work span the continent from Kola in the west to the Laptev Sea in the east. Within this frame our work has concentrated on the Arkhangelsk region in north-western Russia, and the emphasis has been placed on the development of climate and ice sheet through the last 130 000 years BP, the period of the last interglacial and glacial.

Field-work

The expedition in 2001 concentrated on investigating coastal sections and river exposures along the north-western part of Kanin Peninsula and the eastern part of Chyorskaya Bay. Eighteen new sites were recorded in detail, bringing the number of investigated sites since 1995 up to approximately 100 in the Arkhangelsk region. Previous work by such authors as Ramsay (1904) and Spiridonov and Yakovleva (1961) stressed the importance of the Quaternary deposits from these areas for understanding the ice age history of northern Scandinavia. Especially the quickly eroding northern coast of the Kanin Peninsula, with its more than 40 km long and up to 80 m high coastal cliff, presents a unique opportunity to learn the details of the ice age history of northernmost Europe.

Our expedition left Arkhangelsk on a locally charted ship, Akvanaut II, on 23 June to return again on 23 July. Fieldwork was carried out both from the ship and from land-based camps. Two Norwegian, two Danish, one Russian and one Swedish geologist participated. Generally the weather was not bad, but strong winds and long-lasting swells were a hindrance to landing on the exposed coasts, especially at the northern Kanin coast.

The Eemian interglacial

Our record generally starts with the Eemian. At this time a marine transgression flooded the North-Russian lowlands and created a shallow sea extending up to 400 km inland from the present coastline, which for some millennia connected through Karelia to the Baltic. The marine sediments from this period can be seen in coastal cliffs and river bluffs throughout the region and came to the knowledge of the scientific community already through the classical work of Murchison et al. (1845). Later they became known under the name ”the Boreal Transgression” (Chernyschchev 1891), because of their ”boreal” molluscs—i.e. species which now inhabit the Boreal zone and have their northern limit along the coast of Norway or the Murman coast, and do not penetrate into the Barents Sea–White Sea regions.

The marine sediments are usually easy to identify in the field and they provide us with an important marker horizon, giving an immediate indication of the age of over- and underlying strata. The shallow sea contained a wide range of habitats, and their micro- and macro faunas give a detailed insight into the oceanographic and climatic conditions in the White Sea–Barents Sea region 130 000 years ago. These conditions, and especially the White Sea–Baltic seaway, exerted a major influence on the general North Atlantic ocean surface circulation and on European climate (Funder et al. 2001, Funder et al., in press).

Our results indicate that the majority of the occurrences date from a rather short time interval, 1–2 millennia, at around 130 000 years BP during the Early Eemian (Funder et al., in press). At this time global sea-level may have been rising at the unprecedented rate of 4 cm/year (McCulloch and Esat, 2000), and the sea level rise overtook the isostatic emergence after the melting of the ice sheet in the previous ice age, the Saalian of western Europe or Moscowian of Russia. Sea surface temperatures were approximately 5° warmer than now, and there was no sea ice in the winter. Even the interior ramifications of the sea had near-oceanic salinity. After this, isostatic emergence took over and relative sea level began to fall.

Mid Weichselian marine inundation

In the coastal rim of Chyorskaya and Mezen Bays characteristic marine sub-tidal sediments are exposed between two till beds, both younger than the Eemian. The optical stimulated luminescence results show these sediments to be about 60 000 years old, and they record a period in the middle of the last ice age when tides may have been similar to the present in this macro-tide area where the tidal amplitude amounts to 6–10 metres (Nevessky et al., 1977).

At Bolshoi Vzeglavny approximately 50 spring-neap cycles suggest a mean rate of deposition as high as 80 cm/month for this succession alone, and the sparse mollusc shells indicate arctic or subarctic conditions. A shoreline at around 20 m.a.s.l. near the mouth of the Mezen river may date from this marine incursion, indicating that relative sea-level was at least 25 metres higher than present, probably as a result of crustal depression caused by the weight of the Kara Sea ice, which advanced from the northeast. The importance of this new observation lies in the testimony it gives that after a period of ice sheet cover at least the southern Barents Sea was again free of glaciers and open towards the ocean in the middle of the last ice age (Kjær et al., submitted).

Glaciation history

Until recently it was commonly understood that the three North Eurasian ice sheets—the Scandinavian and the Barents and Kara Sea ice sheets—each advanced from different directions to merge over the northern part of the Arkhangelsk region during the LGM, the last glacial maximum approximately 18 000–20 000 years ago, the time when global ice volumes culminated during the last ice age (e.g. Denton and Hughes, 1981). However, the results of the QUEEN project show that the history of the growing and decaying ice sheets was much more complicated. The Barents- and Kara Sea ice sheets apparently had their largest extension in the eastern part of the Arkhangelsk region as early as approximately 70 000 years ago (Svendsen et al., in press), and at LGM the Kara Sea ice sheet had disappeared, while the margin of the Barents Sea ice sheet was well to the north of Russia. Succeeding an ice-free period around 80 000 years BP, ice started to grow on the Timan ridge, spreading westwards and north-westwards into the White Sea and Kanin Peninsula. The full extension of this local land-based ice cap is still unknown. The Scandinavian ice sheet, on the other hand, did not enter the region until about 20 000 years ago, reaching its maximum as late as around 17 000 years ago, when it invaded the western part of the Arkhangelsk region as far east as the Kanin Peninsula (Larsen et al., 1999).

Although it is premature to draw major conclusions from the investigations at Kanin Peninsula and Chyorskaya Bay, it is clear that a till bed deposited by the Kara Sea ice sheet is found throughout the area. Below this, at least one additional till bed is found, indicating glacier movement from the south-east at Kanin peninsula and from the south-west along the coast of Chyorskaya Bay. Whether this is the same stratigraphical till unit or whether they are separated in time and space is still not verified.