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Loess-palaeosol sequences (LPS) represent important records of palaeoenvironmental dynamics throughout the Quaternary. During the Pleistocene's dry and cold phases, the Danube's riverbed was one of the major sources for loess sediments that built up LPS in southern Germany and southeastern Europe. Surprisingly, studies addressing Bavarian LPS along the Danube River often lack actuality. The Attenfeld site was one of them and is often cited as a typical LPS. Nevertheless, the site's previous interpretations are based on a few empirical data and field observations. Considering the site's closeness to the sediment's source area, the Alps, and the region's importance in Middle and Upper Palaeolithic migrational movements, those former renditions needed an evaluation. Therefore, we applied a multi-proxy approach (including analyses of grain-size distribution, element composition, and sediment colour attributes) combined with optically stimulated luminescence. Based on our findings, we conclude that the Attenfeld site's former interpretations might be too generalised. We identified units that were not mentioned by previous studies (e.g. Early Glacial dark greyish horizon). Field observations, sediment characteristics, and age estimates indicate sediment deposition of the dated units partly before MIS 4, which contrasts with previous interpretations. The results further demonstrate how sensitive LPS are to environmental settings and dynamics.

The continuing development of analytical methods for investigating sedimentary records calls for iterative reexamination of existing data sets obtained on loess-palaeosol sequences (LPS) as archives of palaeoenvironmental change. Here, we re-investigate two LPS (Hecklingen, Zilly) in the northern Harz foreland, Germany, being of interest due to their proximity to the Scandinavian Ice Sheet (SIS) and the position between oceanic climatic influence further west and continental influence towards the east. First, we established new quartz OSL and polymineral IRSL chronologies. Both methods show concordant ages in the upper part of the Hecklingen profile (~20-40 ka), but in the lower part IRSL underestimates OSL ages by up to~15 ka for the period 40-60 ka. Interpretations hence refer to the OSL data set. Second, we applied Bayesian age-depth modelling to data sets from Hecklingen to resolve inversions in the original ages, also reducing averaged 1r uncertainty by~19% (OSL) and~12% (IRSL). Modelled chronologies point out phases of increased (MIS 2, early MIS 3) and reduced (middle and late MIS 3) sedimentation, but interpretation of numerical rates is problematic because of intense erosion and slope wash particularly during MIS 3. Finally, previously obtained grain-size data were re-investigated by end member modelling analyses. Three fundamental grain-size distributions (loadings) explain the measured data sets and offer information on intensity and combined with modelled OSL agestiming of geomorphic processes. We interpret the loadings to represent (i) primary loess accumulation, (ii) postdepositional pedogenesis and/or input of aeolian fine fractions, and (iii) input of coarse aeolian material and/or slope wash. The applied modelling tools facilitate detailed understanding of siteformation through time, allowing us to correlate a strong peak in mean grain size at~26-24 ka to the maximum extent of the SIS and increased influence of easterly winds.

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