Isolation basins of Onega Bay – specifics of late- and post-glacial sedimentation according to the study of sediments of Lake Pertozero

Some results of the study of bottom sediments of Lake Pertozero (Onega Coast of the White Sea) are presented – section stratigraphy, loss on ignition, diatom and chironomid analyses. At the initial stage of its development, the lake basin was part of a periglacial basin. Since its isolation around 11000 years ago, the lake has experienced several changes in sedimentary conditions that have affected the amount of organic matter contained in the sediments. These changes are noted throughout the lake. Brackish-water diatom complexes were not noted in the Holocene sediments, which indicates that in this area the sea level did not rise above 11 m.