Significance of bedrock structure and lithology for the glacial valleys distribution and genesis in Belarus

Abstract

Geographic distribution and genesis of glacial valleys within Belarus are closely connected to the structure, deformation properties and lithology of the bedrocks. The study reveals, that the highest valley density is over the protrusions of the Precambrian and Devonian rocks in the Belarusian anteclise and northern Belarus, that have a gently inclination against glacier and are overlied by thin strata of deformable Mesozoic and Cenozoic chalk, marls or uncemented sands and sandstones. In the areas, where the hard Lover Paleozoic and Devonian rocks constitute the bedrock surface in north and east Belarus, glacial valleys are observed in a smaller number. In addition, we find a small number of valleys in areas of southern Belarus, where the Mesozoic and Cenozoic rocks form the bedrock surface, but basement is present of greater depth and dips generally toward to the south. Resistant of the Precambrian and Devonian rocks in northern Belarus to glacial stress and deformable rocks within the Belarusian anteclise predetermined different processes of glacier erosion and favored to development the different types of glacial valleys.