Austrian Journal of Earth Sciences Vienna 2020 Volume 113/1 71 - 86 DOI 10.17738/ajes.2020.0005 Microsedimentology of tills near Ainet, Austria - were palaeo-ice streams in the European Alps underlain by soft deforming bed zones? Jürgen M. REITNER1* & John MENZIES2 1) Geologische Bundesanstalt /Geological Survey of Austria, Neulinggasse 38, A-1030 Wien, Austria 2) Department of Earth Sciences, Brock University, St. Catharines, Ontario, L2S 3A1 Canada * corresponding author:
[email protected] Glacial sedimentology, deformable bed, paleogeography, Last Glacial Maximum, KEYWORDS Alpine Lateglacial, Eastern Alps Abstract Fast moving palaeo-ice masses within the European Alpine Ice Cap (EAIC) during the Last Glacial Maximum within the large valleys of the European Alps are likely comparable in terms of their subglacial conditions to ice streams that drained the larger Quaternary Ice Sheets in Europe and North America. Unlike these continental-style ice sheets, the ice inundat- ing the European Alps, like the Cordilleran Ice Sheet in North America, flowed through confined bedrock valleys that, at close to the glacial maximum, acted in a similar manner to ice streams. Little mention exists as to the extent of soft sedi- ment basal deformation in these deep valleys although increasingly such conditions are known from several parts of the EAIC. The Drau (Drava) ice stream during the Alpine Last Glacial Maximum (= Würmian Pleniglacial, ~ 29 – ~20 ka) as well as small tributary glacier during the early Lateglacial phase of ice decay (~20 – 19 ka) appears as a temperate, fast-moving ice mass that would likely be underlain by soft deforming sediment. It is the underlying microsedimentology of parts of the Drau Valley catchment in the Lienz area of Austria that is the focus of this paper.