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Long-term terrestrial archives of Quaternary climate change illustrate how global changes affect regional climates, but correlation of terrestrial deposits to global records can be challenging due to a lack of material for radiometric dating. The Pannonian Basin (Hungary) contains large river basins, with near-continuous Quaternary deposits ∼600 m in depth. This study tested the IcPD (intra-crystalline protein degradation) approach to amino acid geochronology using bithyniid snail opercula to date deep-core material in geothermally warm regions. Material from seven fully-cored boreholes was collected from four sub-regions: the Körös and Jászság basins, Makó Trough and Békés Basin. IcPD increased with age until approximately 2.3 million years ago, generally supporting stratigraphic correlations previously made between the boreholes. IcPD was consistent between different boreholes within the same sub-region. However due to the steep geothermal gradient in this region, IcPD was systematically different between sub-regions that had different sedimentation rates. Equivalently aged samples buried more deeply had higher IcPD levels, indicating a greater geothermic effect. This provides an insight into how variations in burial temperature can affect protein decomposition within a deeply-buried (>80 m) fossil over geological time, and demonstrates the importance of understanding the geothermal setting for amino acid geochronology. This study shows the utility of IcPD to correlate terrestrial deep-core sediments over the Pleistocene. • The first aminostratigraphy for Quaternary deposits within the Pannonian Basin, Hungary. • IcPD in Bithynia opercula increased with age up to ∼2.3 Ma. • IcPD generally supports stratigraphic correlations previously developed by the multi-proxy age model for these sediments. • Systematic differences in IcPD in opercula >450 ka were observed in different sub-regions due to the steep geothermal gradient. • Knowledge of the geothermal context is essential when building aminostratigraphies for deeply buried Quaternary material. [ABSTRACT FROM AUTHOR]

The Upper Rhine Graben in Central Europe, and notably its depocentre in the Heidelberg Basin, is an archive of complex and long-lasting deposition throughout the Quaternary. A new drill core, 136 m long, from the southern Heidelberg Basin is investigated by characterising sedimentary facies, sediment provenance, as well as analysing the pollen and mollusc content. The chronological framework is based on post-infrared infrared-stimulated luminescence dating, and complemented with amino acid geochronology. The sediment sequence consists of fluvial, colluvial, and palustrine deposits that represent at least the last ∼500 ka, interrupted by some, major and minor, hiatuses. In the lower part, fluvial gravel and colluvial diamicts of a lateral alluvial fan into the Upper Rhine Graben prevail. The central part of the succession consists of a large-scale fining upward cycle that contains increasing amounts of material from the Alps delivered by the Rhine river. This sequence terminates with palustrine fines with rich mollusc and pollen assemblages that allow for a detailed reconstruction of environmental conditions. The results of pIRIR dating place the palustrine deposits in marine isotope stage 11. However, the pollen profile shares similarities with the Mannheim Interglacial that has previously been assigned to the Cromerian, a correlation that is supported by the amino acid geochronology, which poses a chronostratigraphical problem. In the upper part, Alpine sediments are progressively replaced by a new alluvial fan from the graben margin with striking variations in grain size. Overall, the diverse succession is the result of an interplay of tectonic activity and climatic factors. While subsidence triggers the generation of accommodation space and river deflection, pulses of coarse sediment are probably related to periglacial weathering, mass wasting and short-scale transport during cold periods. • Quaternary sediment sequence from the depocentre of the German Upper Rhine Graben. • Fluvial, colluvial, and palustrine deposits representing most of the Mid-Pleistocene. • Interplay of climatic (glacial periods) and tectonic (subsidence) processes. • Palustrine deposits with biostratigraphic and palaeoenvironmental indicators. • Conflicting Holsteinian vs. Cromerian age constraints. [ABSTRACT FROM AUTHOR]