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The Last Climate Cycle (LCC, 130-15kyr) has shown cold, dusty (GS) and warmer, non-dusty (GI) intervals, when the atmosphere was 2-20 times more loaded with dust than today. The alternations between GS and GI occurred on millennial time scales, involving climate forcings other than orbital. The transition between GS and GI lasted on average 50 yrs, resulting from a complete climate reorganization that is not presently understood. A data-model project has acquired and investigated European loess sequences to get high-resolution and well-dated paleodust records of the LCC showing Europe experienced millennial paleodust variations through paleosol-loess unit alternations. These alternations correspond to the millennial climate variability as expressed in the Greenland ice cores, with the paleosol developments occurring during GIs, and loess deposition during GSs. Although evidenced for the last climate cycle along a 50°N transect from Brittany to Ukraine, such system prevailed at least also during the penultimate climate cycle with evidence of similar millennial climate variability during the past 192-130 ka interval, equivalent to marine isotope stage 6. Earth System Models contribute i) to characterize the source regions of the paleodust and ii) to reproduce past variations in dust deposition for key paleoclimate scenarios.A key component of our investigation analyses loess samples dated from the last glacial maximum to detect the origin of the deposited material. A first study on the bulk sediment demonstrates that the paleodust deposited over Europe along a long longitudinal transect (about 2000 km) indicates a short distance transport implying local to regional source. Targeting the

Landscape Evolution Models (LEMs) are powerful tools for simulating erosion and accumulation patterns over a landscape. To accurately capture the complexity of the system, several parameters are used to describe the flow of water on a surface and thereby calculate a change in landscape. However, due to the need for reasonable computing power, simplification is often necessary. The CAESAR-Lisflood LEM simplifies the transition from precipitation to runoff with a cell storage-based system, where water is retained in each cell and released at later iterations, simulating infiltration and forming the hydrograph. This reduced complexity works well for surface processes, but can lead to issues in catchments, where ground water flow and infiltration are unknown parameters, and an unknown proportion of sediment transport is connected to sub-surface processes.Located in the Northern Franconian Jura, Germany, the Weismain River catchment (~125 km2) is a particularly challenging area to model the sediment dynamics, due to its karstic geology. The Weismain river and its tributaries are deeply incised into a limestone plateau forming small, well-defined valleys opening to wider floodplains in the lower parts of the catchment, where sandstone is dominant. To gain a better understanding of the sediment dynamics and the evolution of this catchment, the impact of the karstic environment needs to be evaluated. With CAESAR-Lisflood we are looking at the spatial distribution of alluvial sediment from different model inputs and how differences in discharge calculations affect model results. With this model setup we can gain insight into the sediment dynamics of the catchment and increase confidence in future results.

The μDose system is a recently developed analytical instrument applying a combined α- and β-sensitive scintillation technique for determining the radioactivity arising from the decay chains of 235U, 238U and 232Th as well as from the decay of 40K. The device was designed to meet the particular requirements of trapped charge dating methods and allows the assessment of environmental (i.e. low) levels of natural radionuclides. The μDose system was developed as a piece of low-cost laboratory equipment, but a systematic test of its performance is still pending. For the first time, we present results from a comprehensive performance test based on an inter-laboratory comparison. We compare the results obtained with μDose measurements with those from thick source alpha counting (TSAC), inductively coupled plasma optical emission spectrometry (ICP-OES) and low-level high-resolution gamma spectrometry (HRGS) applied in five participating laboratories. In addition, the reproducibility and accuracy of μDose measurements were tested on certified reference materials distributed by the International Atomic Energy Agency (IAEA; RGU-1, RGTh-1 and RGK-1) and on two loess standards (Nussy and Volkegem) frequently used in trapped charge dating studies. We compare μDose-based results for a total of 47 sediment samples with results previously obtained for these materials by well-established methods of dose rate determination. The investigated natural samples cover a great variety of environments, including fluvial, aeolian, littoral, colluvial and (geo-)archaeological sites originating from high and low mountain regions as well as from lowlands in tropical areas, drylands and mid-latitude zones of Europe, Africa, Australia, Central Asia and the Americas. Our results suggest the μDose system's capability of assessing low-level radionuclide contents with very good accuracy and precision comparable to well-established dosimetry methods. Based on the results of our comparative study and with respect to the practical experiences gained so far, the μDose system appears to be a promising tool for trapped charge dating studies.

When modeling landscape evolution a uniform set of defining parameters is used to describe a heterogeneous landscape. This poses a particular challenge when reconstructing the fluvial history of the Weismain river basin (~125 km2). Located in the Northern Franconian Jura, Germany, the evolution of the landscape is closely related to its underlying bedrock. The Weismain river and its tributaries are deeply incised into a limestone plateau forming small, well-defined valleys that are opening up to wider floodplains in the lower parts of the catchment, where sandstone is dominant. The karstic nature of the catchment complicates a model calibration for the whole basin and therefore the reconstruction of its evolution.In this study, we focus on two sub-catchments of the Weismain River where either lime- or sandstone are prominent. We are using the landscape evolution model CAESAR-Lisflood to model the sediment outputs of those tributaries and compare them to high-resolution, OSL-dated fluvial archives derived from extensive fieldwork. The numerical modeling approach should give insight into geomorphic processes, connectivity inside the system, and the possible impact from sub-surface irregularities in the area.

International audience; Spectroscopic investigations provide important insights into the composition of luminescence emissions relevant to trapped-charge dating of sediments. Accurate wavelength calibration and a correction for the wavelength-dependent detection efficiency of the spectrometer system are crucial to ensure the correct spectrum interpretation and allow for its comparison with those obtained from other systems. However, to achieve an accurate detection efficiency correction, it is necessary to obtain the device-specific spectral response function (SRF). Here, we compare two SRF approximation methods by using either a calibration lamp of known irradiance or calculating the product of efficiency curves provided by the manufacturers of all known optical elements. We discuss the results using radiofluorescence (RF) measurements of two K-feldspar samples as an example. Feldspar infra-red (IR) RF spectra are known to be composed of several overlapping emissions, whose variation with sample mineralogy is still poorly understood and requires more extensive investigations. We find that both methods of sensitivity correction yield broadly similar results. However, the observed differences can alter a spectrum's interpretation. For example, we observe that after peak deconvolution the maximum signal wavelength of the IR-RF peak used for dating applications differs by ∼3–13 nm between the two methods, depending on sample and diffraction grating. We recommend using calibration lamps to determine a device's SRF but highlight the need to consider issues such as higher-order signals in the choice of filters to establish the SRF's reliable wavelength range. Additionally, we find that a simple and inexpensive fluorescent white light yields an acceptable wavelength calibration comparable to that obtained from a specialized light source.

Adolescent idiopathic scoliosis is a disease of the growing skeleton. The goal in therapy is to decelerate or to prevent progression of the spinal curve. As part of a retrospective study the patient group of the scoliosis surgery from 1995-2016 was analysed according to the inclusion criteria of the Scoliosis research Society (SRS). 159 of 643 of the patients fullfilled the specific criteria. The assessment of effectiveness was based on the progression of the angle of curvature. If it was ≤5° it was judged positively. The therapy in accordance to Cheneau is a full-time bracing orthosis. Data from 159 patients - 136 fem. (85.5%), 23 male (14.5%) was analysed. The average age at the beginning of treatment was 13.3±1.7 years. The average duration was 3.47±1.2 years. The average Cobb-angle before treatment was 28.39°±9.44°. At the completion is was 27.7°±12.34°. Stabilisation of scoliosis (≤5°) was achieved for 136 of the patients (85.5%). The final follow-up showed a progression of the Cobb angel5° in 23 cases, of which 19 had to undergo secondary surgery. The length of therapy had a positive influence (p=0.057) on the result. Brace treatment constitutes an effective method of therapy at curvatures between 20-40°. Short duration of therapy correlates with a expressively increased risk towards progression (p=0.057). The Cheneau brace treatment constitutes an effective treatment at curvature angles between 20-40°. The risk of progression can be reduced by a timely and correct identification.Die idiopathische adoleszente Skoliose ist eine Erkrankung des wachsenden Skeletts. Das Therapieziel ist, die Progression der Wirbelsäulenkrümmung zu verhindern oder zu reduzieren. Im Rahmen einer retrospektiven Studie wurden Patienten der Skoliose-Sprechstunde von 1995 bis 2016 bzgl. der Korsetttherapie analysiert. Die Einschlusskriterien entsprachen den Vorgaben von Scoliosis Research Society (SRS) Die Effektivität der Therapie wurde anhand der Progression des Krümmungswinkels bewertet. Bei ≤ 5° wurde der Verlauf als positiv gewertet. Erfasst wurde die Krümmung zum Zeitpunkt der Erstdiagnostik und nach Abtrainieren des Korsetts mit einem follow-up von min. 2 Jahren. Die Therapie erfolgte mit Korsetten nach Cheneau als “full-time-bracing“. Es wurden die Daten von 159 Pat. - 136 weibl. (85,5%), 23 männl. (14,5%) ausgewertet. Das mittlere Alter zu Behandlungsbeginn lag bei 13,3±1,7 Jahren. Die mittlere Behandlungsdauer betrug 3,47±1,2 Jahren. Der mittlere Cobb Winkel vor der Behandlung betrug 28,39±9,44° und zum Abschluss der Behandlung 27,70±12,34°. Eine Stabilisierung der Krümmung wurde bei 136 Pat. (85,5%) erzielt. In 23 Fällen kam es zu einer Progression des Cobb-Winkels von5°, hiervon mussten sich 19 Pat. einer sekundären Operation unterziehen. Die Therapiedauer hatte einen relevanten Einfluss auf das Endergebnis (p=0,057). Die konservative Therapie der adoleszenten idiopathischen Skoliose mittels Cheneau Korsett stellt eine effektive Behandlungsstrategie bei Krümmungswinkeln zwischen 20–40° dar. Bei frühzeitiger korrekter Indikationsstellung und konsequenter Tragedauer lässt sich das Risiko der Progression der Skoliose deutlich verringern.

The Negev Highlands (Israel) are characterized by a rich settlement history over the last millennia. To sustain life in this arid environment, measures to collect and store water were introduced. Two types of installations to collect and store runoff water were built in the region: open reservoirs, and more elaborate subterranean rock-cut cisterns. This article focuses on the latter. Based on a few inscriptions found in rock-cut cisterns, it is assumed that the majority were constructed in the Hellenistic (Nabatean) to Byzantine period. To evaluate this age assessment, this study was carried out at the Borot Hazaz cisterns system, using optically stimulated luminescence (OSL) dating together with micromorphological analyses. Both were applied to sediments that were relocated during the cistern’s construction and usage and after the maintenance activities ended. Despite unfavourable conditions for resetting the OSL signal, including fluvial transport over short distances and sediment deposition by humans in large quantities, it was possible to reconstruct the life cycle of the cistern system. The present study places the construction of the system during the late Roman to Byzantine period, with utilization and long-term maintenance during the following centuries. Maintenance ceased at the Borot Hazaz cistern system gradually over the course of the last 500 years.

The µDose-system is a recently developed analytical instrument applying a combined α- and β-sensitive scintillation technique for determining the radioactivity arising from the decay chains of 235U, 238U and 232Th as well as from the decay of 40K. The device was designed to meet the particular requirements of trapped charge dating methods and allows the assessment of environmental (i.e. low) levels of natural radionuclides. The µDose-system was developed as a low-cost laboratory equipment, but a systematic test of its performance is still pending. For the first time, we present results from a comprehensive performance test based on an inter-laboratory comparison. We compare the results gained with µDose-measurements with those from thick source alpha counting (TSAC), inductively coupled plasma optical emission spectrometry (ICP-OES) and low-level high-resolution gamma spectrometry (HRGS) applied in five participating laboratories. In addition, the reproducibility and accuracy of µDose-measurements were tested on certified reference materials distributed by the International Atomic Energy Agency (IAEA; RGU-1, RGTh-1 and RGK-1) and on two loess standards (Nussy and Volkegem) frequently used in trapped charge dating studies. We compare µDose-based results for a total of 47 sediment samples with results previously obtained for these materials by well-established methods of dose rate determination. The investigated natural samples cover a great variety of environments, including fluvial, aeolian, littoral, colluvial and (geo-)archaeological sites originating from high- and low-mountain regions as well as from lowlands in tropical areas, drylands and mid-latitude zones of Europe, Africa, Australia, Central Asia and the Americas. Our results suggest the µDose-system’s capability of assessing low-level radionuclide contents with very good accuracy and precision comparable to well-established dosimetry methods. Based on the results of our comparative study and with respect to the practical experiences gained so far, the µDose-system appears to be a promising tool for trapped charge dating studies.

There are two main statements of a long-accepted paradigm of fluvial morphodynamics formalized inter alia by S.A. Schumm: (i) changes in fluvial systems strongly depend on exceeding external and / or internal thresholds ​​and (ii) they are always characterized by a nonlinear and asynchronous character. While the first aspect of this paradigm is part of numerous studies on fluvial morphology and river dynamics, the second aspect has so far tended to be sidelined in practical geomorphology.With particular respect to the field of paleo-environmental research, this is evident from studies that aim at determining ages of Pleistocene river terraces in order to provide a time frame for the reconstruction of paleo-environmental conditions. Typically, numerical dating approaches are only applied to a single location that is supposed to be exemplary for the respective terrace level. Numerical ages determined for this specific location are then extrapolated and interpreted in a generalizing way to derive "THE age" of the river terrace as a whole.With respect to the concept of asynchronism of fluvial reactions to environmental changes, such an approach seems problematic. In fact, asynchronism implies different sections of a river showing different and specific reactions to environmental changes at a given point in time. For fluvial terraces, this means that the processes controlling their formation may already have started in some sections of a valley, while in other sections they do not yet have any impact on landscape evolution.In this contribution, we present luminescence ages of fluvial deposits originating from an Upper Pleistocene river terrace in a small valley located in the headwater of the Main River, Germany. Here, several samples from various locations throughout the river longitudinal course have been analysed. The luminescence ages determined for the lowermost part of the valley are significantly older than those from the middle section, which in turn are older than those from the valley’s upper reaches.Our results suggest a diachronic alignment of sedimentation ages for fluvial deposits, starting with old ages close the mouth of a river and getting progressively younger for locations approaching the upper reaches. If these findings are confirmed in other fluvial systems and are not only the result of specific local conditions, they will be of great relevance for geomorphological research in fluvial landscapes. As a result, the widespread approach of deriving age estimates for fluvial terraces from numerical results merely determined for a single location appears to be inadequate and should be subjected to a critical review.

We present a multi-proxy approach to reconstruct Middle Bronze Age (MBA, 1600-1250 BCE) land use practices in the north-western Alpine foreland (SW Germany, Hegau). We combined biogeochemical proxies from multi-layered colluvial deposits and archaeobotanical and archaeozoological data within and in the surrounding of the archaeologically well-documented settlement site of Anselfingen. Offsite pollen data from two peat bogs were used to place the onsite and near-site vegetation and land use data to a regional context.Phases of colluvial deposition were reconstructed by optically stimulated luminescence (OSL) and radiocarbon (AMS 14C) dating. The first phase of major colluviation could be correlated with MBA land use followed by phases of colluvial deposition during the Iron Age, the Medieval period, and modern times. Charcoal spectra from colluvial deposits and archaeological structures indicate MBA forest management favoring Quercus in the surrounding area north of the settlement. The analysis of faecal biomarker (5ß-stanols up to 40 %) and excavated pig bones (up to 14 %) suggest the presence of a forest pasture mainly used for pig farming. In the surrounding area south of the settlement, an arable field with a buried MBA plough horizon (2Apb) could be verified by soil micromorphological features such as very dusty clay coatings and a banded microstructure and by high concentrations of grass phytoliths from leaves and stems. Agricultural practices (e.g. ploughing) focused on five staple cereal crops (Hordeum distichon/vulgare, Triticum dicoccum, Triticum monococcum, Triticum spelta, Triticum aestivum/turgidum) as indicated by the onsite archaeobotanical records. Stilted pantries, reconstructed from MBA post-holes, were interpreted as storage facilities, while excavated heat stones are likely to indicate post-harvest processing of cereal crops and other agrarian products. Higher levels of urease activity compared to microbial biomass carbon (up to 2.1 µg N µg Cmic-1), and input of herbivorous animal faeces indicate livestock husbandry on fallow land or manuring practices. The suites of polycyclic aromatic hydrocarbons (PAHs) and their spatial distribution indicate the use of fire for various purposes, e.g. for landscape opening and maintenance, for domestic burning and for technical applications. The offsite pollen data support the onsite and near-site vegetation change. During the MBA, fire played a major role in shaping the landscape (peak of micro-charcoal during the MBA in the offsite pollen records) and anthropogenic activities promoted oak dominated forest vegetation at the expense of natural beech forests. This approves a broad regional human influence in the north-western Alpine foreland during the MBA.Our data allow in-depth insights into the MBA subsistence economy on a local and regional scale, which was not limited to settlements at lakeshore sites. The MBA in the north-western Alpine foreland was a period of establishing settlements with sophisticated land management and land use practices also at low and mid altitude inland sites. We could further show that colluvial deposits are promising archives for the reconstruction of past land use practices.

Cortical excitability, the variable response to a given cortical input, is widely studied in neuroscience, from slice experiments and in silico modeling work to human clinical settings. However, a unifying definition and a translational approach to the phenomenon are currently lacking. For example, at the onset of epileptic seizures, cortical excitability may impair resilience to perturbations (external or endogenous). In this study, we tested in vivo whether changes in cortical excitability quantified as evoked response to small perturbation corresponded to changes in resilience to larger perturbations. To do so, we used both cell-type circuit specific optogenetic stimulation in mice and direct intracranial stimulation in one human subject and quantified 1) evoked cortical responses to single pulses of varying intensity, and 2) evoked cortical facilitation and suppression to paired pulses at varying intervals. In the presence of a gamma-Aminobutyric acid (GABA) agonist or antagonist, we found that 1) cortical response to single pulses and 2) cortical facilitation decreased and increased, respectively. Additionally, using trains of opto-pulses in mice in the presence of a GABA agonist, we found increased resilience to the induction of seizures. With this study, we provide evidence for a tight correlation between cortical excitability and resilience, exploring a range of cortical dynamics, from physiological excitability, to pathological discharges. Our study carried out with two different stimulation methods in two species suggests that varying cortical excitability can be tracked with simple protocols involving minute short-lived perturbative stimuli.

This paper aims to reconstruct Middle Bronze Age (MBA; 1600–1250 BCE) land use practices in the northwestern Alpine foreland (SW Germany, Hegau). We used a multi-proxy approach including the analysis of biogeochemical proxies from colluvial deposits and buried topsoils in the surroundings of the well-documented settlement site of Anselfingen and off-site pollen data from two peat bogs. This approach allowed for in-depth insights into the MBA subsistence economy and shows that the MBA in the northwestern Alpine foreland was a period of establishing settlements with sophisticated land management and land use practices. The reconstruction of phases of colluvial deposition was based on ages from optically stimulated luminescence (OSL) and radiocarbon (AMS14C) dating from multi-layered colluvial deposits and supports the local archaeological record with the first phase of major colluvial deposition occurring during the MBA followed by phases of colluvial deposition during the Iron Age, the Medieval period and modern times. The on-site deposition of charred archaeobotanical remains and animal bones from archaeological features, as well as polycyclic aromatic hydrocarbons (PAHs), charcoal spectra, phytoliths, soil microstructure, urease enzymatic activity, microbial biomass carbon (Cmic) and heavy metal contents from colluvial deposits, were used as proxies for on-site and near-site land use practices. The charcoal spectra indicate MBA forest management which favored the dominance of Quercus in the woodland vegetation in the surrounding area north of the settlement site. Increased levels of 5β stanols (up to 40 %) and the occurrence of pig bones (up to 14 %) support the presence of a forest pasture mainly used for pig farming. In the surrounding area south of the settlement, an arable field with a buried MBA plow horizon (2Apb) could be verified by soil micromorphological investigations and high concentrations of grass phytoliths from leaves and stems. Agricultural practices (e.g., plowing) focussed on five staple crops (Hordeum distichon/vulgare, Triticum dicoccum, Triticum monococcum, Triticum spelta, Triticum aestivum/turgidum), while the presence of stilted pantries as storage facilities and of heat stones indicate post-harvest processing of cereal crops and other agrarian products within the settlement. In the area surrounding the settlement, increased levels of urease activity, compared to microbial biomass carbon (up to 2.1 µg N µg Cmic-1), and input of herbivorous and omnivorous animal faeces indicate livestock husbandry on fallow land. The PAH suites and their spatial distribution support the use of fire for various purposes, e.g., for opening and maintaining the landscape, for domestic burning and for technical applications. The off-site palynological data support the observed change in on-site and near-site vegetation as well as the occurrence of related land use practices. During the Early and Middle Bronze Age, fire played a major role in shaping the landscape (peak of micro-charcoal during the MBA), and anthropogenic activities promoted Quercus-dominated forest ecosystems at the expense of natural beech forests. This indicates a broader regional human influence in the northwestern Alpine foreland at low- and mid-altitude inland sites during the Middle Bronze Age.

Stone pavements are typical landforms in arid environments, composed of a monolayer of clasts at the surface, associated with an underlying unit of eolian fines. They represent important paleoenvironmental sediment archives, for which reliable chronostratigraphic age constraints are needed. In a first study on stone pavements from the Mojave Desert/USA and Badia Desert/Jordan it could be demonstrated that optically stimulated luminescence dating (OSL) on quartz represents a promising dating method for the eolian fines, but quartz OSL results remained challenging, because the De distributions were unexpectedly broad and OSL fine- and coarse-grain ages were significantly different (Fuchs et al., 2015). The reason for this age difference was unclear and methodological as well as geomorphological arguments were proposed. Here we present new quartz OSL results from additional study sites and various environmental settings, to better understand possible methodological or geomorphological reasons for the previously detected age characteristics. Stone pavements from the Negev Desert/Israel, from Fuerteventura/Spain and from the Black Rock Desert/USA are investigated in this new study, and their OSL results derived from different grain sizes are compared and discussed.

In many Central European river catchments changes in long-term sediment dynamics are caused by external driving forces (e.g. human impact, climate change). In addition, the sensitivity of fluvial systems to environmental change is controlled by the catchment’s geomorphic connectivity of individual sediment sinks. In this study, we reconstruct the temporal evolution of different types of sediment reservoirs along the sediment cascade in a mesoscale upland catchment to assess its sensitivity to external changes. The chronological evolution of hillslope and floodplain sediments is based on 79 OSL and 83 C14 ages. Our results show that deposition of hillslope sediments coincides with the first evidence for human-induced soil erosion triggered by the earliest European farmers, but were decoupled from the river network for more than two millennia when the aggradation of overbank fines started and steadily increased. Therefore, the connectivity between the colluvial and alluvial sediment sinks of the catchment is mainly controlled by the landscape geometry and frequency and magnitude of erosion, transport and deposition processes.

Revealing an amazing diversity of forms, river systems have always to be interpreted as products of their specific landscapes. Extremely sensitive to external and internal forcing, they reflect the particular characteristics of climatological and geological conditions as well as the changes of these conditions. These changes are regularly preserved in depositional series whose varying sedimentary characteristics can be attributed either to palaeoclimatic variations or to tectonic activities and their corresponding changes in fluvial discharge and sediment load. What applies to fluvial sediments in general, is particularly true for river terraces. Regularly, they are regarded as valuable palaeoenvironmental and archaeological archives and their particular importance is well documented by a huge and still growing number of studies spanning a wide range of climatic and regional settings.However, the information gained from fluvial terraces and their significance for palaeoenvironmental and present-day fluvial research strongly depend on an accurate and precise dating of the terrace formation. Numerical ages are of fundamental importance for the interpretation of sedimentological, morphological and stratigraphical findings. They are essential for assessing the influence of various driving forces and for providing insights into the mechanisms and dynamics of river adjustments over variable temporal scales.In this contribution, we present luminescence ages of fluvial deposits originating from an Upper Pleistocene river terrace in a small valley located in the headwater of the Main River, Germany. For this study, several samples from various locations throughout the river longitudinal course have been analysed. Surprisingly, the determined luminescence ages for material from the lowermost part of the valley are significantly older than those from the middle section, which in turn are older than those from the valley’s upper reaches. Based on the evaluation of a high-resolution digital elevation model (DEM) and on intensive fieldwork, we can be sure that all samples originate from the very same morphological unit, a well-preserved late Pleistocene fluvial terrace.Our results suggest a diachronic alignment of sedimentation ages for fluvial deposits, starting with old ages close to the mouth of a river and getting progressively younger for locations approaching the upper reaches. If these findings are confirmed in other fluvial systems and are not only the result of very specific local conditions, they will be of great relevance for geomorphological research in fluvial landscapes. As a result, the widespread approach of deriving age estimates for fluvial terraces from numerical results merely determined for a single location appears to be inadequate and should be subjected to a critical review.

Quartz optically stimulated luminescence (OSL) and post-IR IRSL dating of potassium-rich feldspar separates were applied to fluvial sediments which had been supposed to be of pre-Eemian (pre-MIS 5e) age. Our aim was to establish a reliable chronology for the upper three terrace levels from a sequence of five fluvial terraces in a region of Northern Bavaria (Germany) characterized by a complex Pleistocene fluvial history. The investigated quartz samples proved to be in dose saturation and the calculated OSL ages could only be interpreted as minimum age estimations. The performance of the used pIRIR225-approach was tested by a set of bleaching experiments, dose recovery tests (DRT) and measurements of sample specific laboratory fading rates. Despite applying a pIRIR225-protocol, the phenomenon of ‘anomalous fading’ remained a major problem for age calculation in this study. Although various fading correction methods were applied, only the model proposed by Huntley and Lamothe (2001) could successfully be used. Overall, the corrected pIRIR225-ages were in good agreement with age constraints derived from stratigraphical and sedimentological findings. For some feldspar samples, however, the determined ages were far beyond a realistic age range for a meaningful interpretation when considering the (morpho-)stratigraphical setting. Although the reasons for these significant age overestimations are not clear so far, they might either indicate methodological limitations of the post-IR IRSL approach or point to serious problems attributed to the luminescence properties of the used K-feldspar separates or to the specific regional environmental settings during sample deposition. Despite these problematic findings, the numerical results derived from the post-IR IRSL measurements could be used to establish a preliminary chronological framework for the various evolutionary stages identified for the research area.