The maximum ice-sheet extent of a glaciation or glacial phase is in most cases indicated by the position of end moraines. In some cases, however, the maximum extent of the ice sheet is indicated by a fan which represents the transitional zone between the end moraine and the proximal outwash plain (sandur). Such a fan from the Pomeranian phase near Charlottenthal in NE Germany has been investigated for its lithofacies, and the depositional mechanisms of the two sedimentary environments (end moraine and outwash plain) are reconstructed. The Charlottenthal profile is not characteristic in a sedimentological sense of a typical marginal end moraine or a sandur. The deposits represent subaerial debris flows, sheet floods and channelized currents, which are typically processes for transitional fan. Gravel samples from the till complex show typical Weichselian till compositions. These till compositions indicate a general transport direction from North to South, which is consistent with the known movement of the ice sheet during the Pomeranian phase of the Weichselian.
The petrographic and mineralogical characteristics of glacial deposits from the localities in the northern foothills of the Hruby Jesenik and Rychlebske Mts. have been studied. Grain-size, petrographic composition, heavy minerals, clast shape and roundness have been investigated. The data obtained have been used to create a probability model to differentiate the stratigraphy of particular accumulations and for partial reconstruction of the advance direction of the ice sheet in the area. The main advance direction of the ice sheet was presumed to be from the NW to SE in this region. The erratic material was probably predominantly transported in the basal ice layers according to the clast shape and roundness. An Elsterian age of the sedimentary bodies investigated is suggested by correlation with analogous deposits in adjacent parts of Poland. This model contradicts previous correlations. However, further constraints on the stratigraphic position of these deposits would require the application of dating techniques.
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