During the penultimate glaciation vast areas of the Alps were glaciated, with piedmont glaciers protruding
into the foreland. In the easternmost part of the northward draining valleys of the Alps, the
glaciers did not reach the foreland, but formed valley glaciers confined by the mountainous terrain. This
also applies to the Ybbs valley, where samples for luminescence dating out of glaciofluvial gravel accumulations
were taken at three locations along the present day river course. In a highly dynamic
depositional environment, such as a glacier-fed river system, incomplete resetting of the luminescence
signal is possible, in particular when transport distances are short. In such cases, quartz usually is the
preferred mineral over feldspar, especially if dose rates are low and may theoretically allow obtaining
quartz ages beyond 150 ka. Because previous research has shown, and as corroborated within this study,
quartz from the research area exhibits analytical problems in the high age range. Therefore luminescence
properties of coarse grain (100e200 mm) quartz and in addition K-rich feldspar were investigated with
the aim to reconstruct the chronology of the glacial processes within the Ybbs catchment area. Issues of
incomplete bleaching were pIRIR225 encountered and addressed by comparing quartz OSL, fading corrected
K feldspar IR50 and pIRIR225 to identify reliable ages. Depositional ages based on quartz OSL and
feldspar pIRIR225 signals revealed deposition of ice marginal kame terraces and glaciofluvial foreland
terraces during late to middle MIS 6. In combination with results from previous studies, we could
reconstruct the valley evolution during the Riss glaciation. Newly gained luminescence ages of the
deglaciation in the easternmost Alps coincide with OSL dated deglaciation events in the Western Alps,
indicating that climatic change along the north side of the Alps happened simultaneously.
© 2014 The Authors. Published by Elsevier Ltd and INQUA. This is an open access article under the CC BY