Glacial tills and fluvioglacial sediments deposited by the ice-sheet during the Pomeranian Stage (Weichselian) in northeast Germany have been examined in terms of the degree of abrasion, rounding and frosting of quartz grain surfaces in order to determine the conditions and processes that occurred in the alimentation environment of the fine-grained material, as well as during transport. Strata in the glaciomarginal zone and the hinterland of the Pomeranian Stage in the area represent diverse lithofacies, but have similar textural features. These features illustrate mainly that a high-energy aquatic environment had reacted with glacial deposits prior to their inclusion into the ice mass and deposited in the area covered by the Odra lobe. The lack of regional diversification in the character of quartz grain surfaces in glacial deposits between the German part of the Odra lobe and the remainder of the area analysed is recorded solely in the morphological dimension, i.e. the outlet fragment of the ice-front’s course, but not in textural features of the sediments.
The Brandenburg section of the hinterland and of the maximum extent of the Pommeranian phase of the last glaciation, formed in two lobes (Schulz, 1967): Joachimsthal-Ringenwalder and Ucker-markischer, have been covered by a study on petrography of a gravelly and a stony fraction. The methods applied followed suggestions of Bose (1989), Trembaczowski (1961, 1967), Meyer (1983), Smed (1993, 1994) and Zandstra (1999). Petrographical analyses undertaken in Uckermark, NE Germany, were focused on: 1) observation of the dynamics of petrographical features along and in the hinterland of the Odra lobus on the German side, 2) indication of the western limit of the Odra lobus upon petrography of glacial sediments, 3) indication of Scandinavian parent areas of sediments of the Pommeranian phase and estimating the routes of ice-sheet onto German Lowland. The distance between outcrops of Scandinavian rocks causes the number of erratics in sediments of glacial accumulation in the German part of the Odra lobus. There are more Mesosoic rocks in the gravelly fraction as compared with sediments of the same age, but sampled in the Polish part of the Odra lobus. The stony fraction (20-60 mm) is represented mainly by indicator erratics from Smĺland and the Swedish coast in Kalmar Strait. Ĺland erratics, quite frequent in Polish lowlands, are observed rarely in Uckermark. Among statistical erratics there are numerous flints and Mesosoic limestones as well as Lower-Palaeozoic limestones. The theoretical stone centre moves its locality within middle-southern Smĺland.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.