O.YU. NOSOVA, A.A. VASHKOV (GI KSC RAS)

Lithologic composition of coarse clastic fraction of the tillite from the west part of the Terskie Keivy glacial accumulative complex, southern Kola Peninsula

Petrographic composition of till coarse-clastic fraction in the west part of the Terskie Keivy studied near the Varzuga Village is dominated by sandstone and siltstone of the Riphean Olenitsky Series and various granitoids of the Middle Lopian migmatite-diorite complex and the Late Lopian migmatite- and anatektite-granite complex, which are bedrock or occur near the study area. Clasts of rocks transported from the central and south-western part of the Kola region were found. Petrographic composition and other characteristics of studied glacial deposits from the ridges of the western Terskie Keivy evidence that they formed in an open stream flow. In the current relief, they correlate to eskers, which mark the peripheral zone of the White Sea Ice Stream during a phase of its retreat.
Keywords: ice marginal deposits, eskers, fluvioglacial material, glacier dynamics.