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During the last glacial maximum (LGM), large parts of the European Alps were occupied by an extensive interconnected system of valley glaciers. At lower elevations on the eastern fringe of the Alps, only a patchy pattern of isolated glaciers developed. Erosion by many of these smaller glaciers was however sufficient to excavate subglacial basins ('overdeepening') large enough to act as sedimentary archives of deglaciation processes. To constrain the deglaciation history and the post-LGM evolution of an isolated glacial system, we analyzed the geomorphology and the sedimentary record of a local overdeepening at the northern fringe of the Northern Calcareous Alps. We focus on the heavily silted lake system Taferlklaussee (TKS) (Höllengebirge massif, Austria) confined by a succession of terminal moraines and a steep headwall. Field techniques (mapping, Direct Current Resistivity, and core drilling), lab techniques (lithostratigraphic analyses and radiocarbon dating) and Geographic Information System (GIS) analyses are employed to document dynamics of erosion and sedimentation after deglaciation. We discuss drivers and controls of paraglacial landscape evolution. The almost complete postglacial (lake) record indicates abundant sediment input during the lateglacial and early Holocene, but strongly reduced dynamics since the Mid-Holocene. Sediment storage volumes range between 3.83 Mm³ and 5.75 Mm³ and lithology-specific mechanical denudation rates range between 0.8 mm/a and 1.7 mm/a depending on the scenario used. The study provides a well-constrained reference for the depositional dynamics of isolated LGM glacier systems of the Eastern Alps. It highlights the potential of using related sedimentary records to constrain the local variability in postglacial landscape evolution. [ABSTRACT FROM AUTHOR]

A complex ice stream network occupied the European Alps during the last glacial maximum (LGM, MIS 2, Würmian Pleniglacial) with large valley glaciers extending as piedmont lobes into the northern and southern forelands. A completely different situation is reported for the easternmost Alps, where only a patchy pattern of isolated glaciers, confined to minor valleys, localized cirques and small plateaus could develop. Although the Alpine LGM glaciation was intensively studied, data sets vary considerably in the easternmost Alps (e.g concerning the numbers of local glaciers as well as extents) and systematic analyses of the glacial record are missing for the entire region. Consequently, equilibrium line altitudes (ELAs) and ELA depressions (ΔELAs) for these paleo glaciers remain unknown as well, though such data can be extremly useful to provide information on the variance of atmospheric circulation patterns over glacial to interglacial timescales. Characterized by relatively simple geometries and obviously rather simple source area relations (compared to the ice-stream network in the central Alps), they are most suitable for paleo-glacier reconstruction and ELA modelling – and can provide a robust dataset on ELA depression variabilities during the LGM. Such analysis is hardly possible for the ice-stream network occupying most of the central Alps at the same time.To fill this gap, we provide a new GIS-dataset of the LGM glaciation at the Eastern Alps based on the principal work of van Husen (1987), a number of case studies, geological maps, and the analyses of multiple orthophoto and DEM data. First systematic analyses on ELAs and ELA depressions of these low elevated isolated glaciers highlight the highly variable glacier response across the Eastern Alps to topographic and climatic forcing. [ABSTRACT FROM AUTHOR]