Development of the topography-controlled Upper Odra ice lobe (Scandinavian Ice Sheet) in the fore-mountain area of southern Poland during the Saalian glaciation

摘要: Abstract During the Saalian (Drenthe) glaciation, Upper Odra ice lobe constituted most southern part of Scandinavian Ice Sheet in central Europe. The was situated an area with varied topography foreland a mountain range. had complex form because it subdivided into several smaller sublobes. primary factors that controlled were investigated. It found ice-lobe development depended largely on topography, but lithology sheet substratum also highly important. main movement direction and caused concentration flow axial Silesian Lowland between subglacial morphological barriers, which thereby formed corridor relatively fast flowing ice, probably streaming supplied lobe. determined within lobe, strongly matched valley system. presence sediments low permeability at base (the Quaternary deposits are underlain by Neogene clays) high pore-water pressure zone triggered basal sheet, promoted rapid favoured tills deposited from active passive extant till patches without fluvioglacial cover atop some parts studied indicate spatially varying dynamics, especially later stage glaciation. Certain underwent stagnation, while other parts, still active. behaviour primarily substratum, produced marginal compression friction. A model is proposed.