A. V. Amantov, M. G. Amantova
Implication of glacial theory to the development of the Lake Ladoga basin
The general concept of the formation of pre-Quaternary surface and, in many ways, the modern landscape of Lake Ladoga is discussed as a result of geological-geomorphological analysis including specialized computer modeling systems, with implications of aspects of the glacial theory. Complex glacial and fluvio-glacial denudation served a determining factor in the development of structural-denudational forms of various order. We propose existence and specification of the independent family of non-mountain cirques created by ice sheets. It includes giant Severoladozhsky (North Lake Ladoga) cirque representing the largest corrie in the world, as well as Landsort – the deepest basin of the Baltic Sea. In this case a glacial cirque is determined as an amphitheatre-shaped overdeepened basin, with close values of length and width, steep headwall, side slopes and pronounced lip; the basin is usually located within the ice stream, which produces a typical specific contrast terrain profile in geologically and geomorphologically predetermined locations.
Key words: ice sheet, glacial erosion, cirque, corrie, Lake Ladoga, terrain, geomorphology.