Holocene Relative Sea-Level Changes Reconstruction in the North−West of Onega Peninsula (Konyukhov Bay, White Sea) Based on Paleolimnological Studies

diatom analysis and radiocarbon dating of samples of bottom sediments of Lake Konyukhovskoye (64.882° N, 36.586° E) with a hypsometric level 15.8 m and a runoff threshold of 17.0 m a.s.l. are presented. The results of the analysis of bottom sediments allowed reconstructing the history of the lake and changes in the level of the White Sea in the Holocene. For the first time, Lake Konyukhovskoye was isolated during the Early Holocene regression earlier than 10.2 thousand cal. years BP. Sea conditions and the connection with the White Sea arise during the Tapes transgression ~9.0–8.8 thousand cal. years BP. The relative sea level during the maximum of the transgression was ~17.5 m a.s.l. The final separation of Lake Konyukhovskoye occurred as a result of a drop in sea level below 17.0 m earlier 6.9–6.8 thousand. cal. years BP.

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