(March): Isolation basin stratigraphy andHolocene relative sea-level change at the Norwegian-Russian border north of Nikel, northwest Russia. Boreas, Vol. 28. pp. 146166. Oslo. ISSN 0300-9483. The marine-lacustrine transition (isolation contact) in sediment cores from eight lake basins situated 13.5-72 m a.s.1.. in the Nonvegian-Russian border area north of Nikel, northwest Russia, was identified based on Lithological and diatom analysis, radiocarbon dated, and used to construct a relative sea-level (RSL) curve for the Holocene. All the lakes except one (interpreted as having an unconformable slumped transition) show a regressive 1-11-111 (marine-transitional-lacustrine) facies succession, indicating a postglacial history of continuous emergence. The RSL curve shows rapid emergence between 10000 and 8000 BP, very slow emergence between 7000 ahd 5000 BP, increased rate of emergence between 4500 and 4000 BP, and a moderate rate of emergence after 3500 BP. The low rate of emergence around 6000 BP correlates with the Tapes transgression of more coastal regions, but corresponding sea level, at 25-26 ma. present s.l., lies 5-10 m lower than the elevation predicted based on existing isobase maps for the region. The discrepancy suggests a need for further work in order to more rigorously define and map the Tapes transgression and associated shoreline complex in the northern Fennoscandian-Kola region.

Sedimentary records of invertebrate assemblages were obtained from a small lake in the Khibiny Mountains, Kola Peninsula. Together with a quantitative chironomid-based reconstruction of mean July air temperature, these data provide evidence of Holocene climate variability in the western sector of the Russian Subarctic. The results suggest that the amplitude of climate change was more pronounced in the interior mountain area than near the White Sea coast. A chironomid-based temperature reconstruction reflects a warming trend in the early Holocene, interrupted by a transient cooling at ca. 8500–8000 cal yr BP with a maximum drop in temperature (ca. 1°C) around 8200 cal yr BP. The regional Holocene Thermal Maximum, characterized by maximum warmth and dryness occurred at ca. 7900–5400 cal yr BP. During this period, July temperatures were at least 1°C higher than at present. The relatively warm and dry climate persisted until ca. 4000 cal yr BP, when a pronounced neoglacial cooling was initiated. Minimum temperatures, ca. 1–2°C lower than at present, were inferred at ca. 3200–3000 cal yr BP. Faunal shifts in the stratigraphic profile imply also that the late-Holocene cooling was followed by a general increase in effective moisture.

We report here on cirque infills mapped in the Khibiny Mountains, Kola Peninsula, Russia. Cirque infills are morainic deposits located near the headwalls of valleys and cirques. Their location and shape, often with concave margins towards the valley side, indicate that they were deposited by ice flowing up-valley, into the mountains, rather than by local glaciers. We suggest that they formed during the last deglaciation, when Khibiny was a nunatak and Fennoscandian ice sheet lobes extended into valleys and cirques of the massif. The formation of cirque infills is probably more related to ice sheet dynamic factors, occurring when the ice margin retreated from the cirques, than to climate-driven interruption in the ice-marginal retreat. Glacial conditions similar to those prevalent when the Khibiny cirque infills were formed, occur today in Antarctica where the ice sheets engulf nunatak ranges. In Heimefrontfjella, Antarctica, the formation of supraglacial moraines at the head of cirques are linked to blue-ice conditions, indicating locally low accumulation rates, a dry continental climate and sublimation dominated ablation. We suggest that these Antarctic moraines are modern analogues of cirque infills on the Kola Peninsula, and possibly, that the cirque infills may be used as palaeoenvironmental indicators.