Geomorphology of Lake Ladoga basin

Abstract

This work presents results of geomorphological analysis of the Ladoga lakes bottom, based on geophysical and bathymetrical data. The final approach of this investigation is geomorphological scheme with scale 1:1 000000. The digital elevation model of M.A. Naumenko with spatial distribution 0,5 X 0,5 was used as a bathymetrical base. Geophysical part of data are seismoacoustic profiles covering the whole basin with total length in 1304 km. They were received in expeditions of St. Petersburg University, Marine Research Center at Moscow State University and Northern Water Problems Institute KarRC RAS. Geomorphological analysis allows us to mark 6 genetic types. Two types was related to denudative types (denudative structural and erosive subaqual) and four to accumulative types (glacial, fluvioglacial, glacial lacustrine and lacustrine). Four main factors in to form of bottom structure Lake Ladoga during the Late Glacial-Holocene were identified. A neotectonical factor was mostly significant. In addition, there were exogenous factors to form sediment cover of the basin: glacial activity, glacial lacustrine accumulation of varved clays and modern processes of lacustrine accumulation and abrasion of older sediments.