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Paleosol horizons preserved in loess-palaeosol sections (LPS) provide valuable archives of Quaternary palaeoenvironmental changes over time and spatial palaeoenvironmental gradients during the same period. Here, we present the characteristics of paleosol horizons in two LPS near the western edge of the Rhône Rift Valley in southeastern France: (1) the LPS “Baix” (total thickness: 14 m), located about 17 km north of Montélimar (44°42’36”N, 4°43’21”E), thus, in the transition zone between the presently temperate and the Mediterranean region of Europe; (2) the LPS “Collias” (total thickness: 9 m), located in the Uzès Basin, about 15 km northeast of Nîmes (43°57’11.94”N, 4°27’56.71”E), thus, in presently fully Mediterranean climate. Investigation of the paleosol horizons in the main profile at Collias was complemented by those of three smaller nearby LPS, “Collias-North_D112” (43°57’12.55”N, 4°27’55.83”E), “Collias-South_D112” (43°57’12.44”N, 4°27’53.36”E), and “Collias-North” (43°57’21.67”N, 4°28’6.99”E), in order to capture the spatial variability of the characteristics of some key horizons.To our knowledge, no LPS have been analysed yet in such a transitional position between the presently temperate and Mediterranean climate. Primarily the LPS Baix may provide a crucial link between the rigorously analysed LPS in the presently temperate regions further north (e.g., in northern France, the Alsace region and Germany) and the LPS in the Mediterranean region (e.g., in southern France, Catalonia, Italy and Croatia), including the LPS Collias. Therefore, we aimed to decipher the paleoenvironmental record of the LPS Baix and Collias, and to identify similarities and differences between them. Optically stimulated luminescence (OSL) dating provided a chronological frame for both LPS.The basal part of the LPS Baix starts with reddish Bt(g) horizons of a Stagnic Luvisol, representing the remains of an Eemian to Early Würmian (MIS 5) pedocomplex formed under warm and - at least temporarily - relatively moist conditions. The corresponding pedocomplex in the profile Collias-North_D112 displays an intensive red (chromic) Bt horizon overlain by several Bw horizons formed in reworked soil sediment and underlain by a massive calcrete. In the main profile at Collias, this red horizon has been entirely reworked by slope processes and has regained an angular blocky structure afterwards. Thus, it appears as a dark orange-red Bw horizon. Both, the LPS Baix and Collias include a prominent brown Bw horizon of a truncated Cambisol that developed in middle Pleniglacial (MIS 3) deposits. It is associated with large, elongated, vertically oriented calcium carbonate nodules, indicating that considerable amounts of calcium carbonate must have been leached from the former middle Pleniglacial Cambisol and accumulated in the underlying loess unit. No distinct palaeosols were observed in the Late-Pleniglacial deposits of the LPS Baix and Collias; a slightly brownish colour indicates very weak weathering (several BCk horizons) in the Late-Pleniglacial sediments of both LPS.

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.

The term “Bergstraßenneckar” (BSN) refers to an abandoned course of the river Neckar. It flowed in a northern direction east of the river Rhine in the eastern part of the northern Upper Rhine Graben in southwestern Germany. The former meandering course merged with the Rhine ca. 50 km further north of the site of the present-day confluence near Mannheim. The palaeo-channels are still traceable by their depressional topography, in satellite images and by the curved boundaries of adjacent settlements and land parcels. In the plan view, satellite and aerial images reveal a succession of meander bends, with older bends being cut off from younger channels. Based on stratigraphic investigations of the channel infill in the northern part of the BSN, fluvial activity is assumed from ca. 14 500 years ago until the onset of the Holocene. We present results of the first stratigraphic investigations at two sites in the southern part of the BSN near Heidelberg (Rindlache, Schäffertwiesen), together with results from granulometric, carbonate and organic content analyses, as well as electrical resistivity tomography (ERT) measurements. The data clearly show a change from high-energy fluvial bedload (sand, gravel) to low-energy fluvio-limnic suspended load (organoclastic and calcareous mud) and to peat formation. Radiocarbon dating indicates a time lag of ca. 1500 years between the cut-off meander site (Schäffertwiesen) and the younger site (Rindlache) that was possibly still active until the present-day confluence near Mannheim was established and the BSN eventually became abandoned. Our preliminary data conform with the pedo-sedimentary evidence from the northern BSN, but slight differences in the stratigraphic pattern of the youngest channels are identified: whilst for the younger channel sections of the northern BSN the channel-bottom facies (sand, gravel) is directly overlain by peat, the channel at Rindlache shows substantial intervening mud deposition, which is interpreted as suspension load from flooding by the new Neckar channel nearby. The study shows that more chronostratigraphic data from channel sections of the southern BSN are needed to better constrain the timing of the fluvial activity and to decipher the reasons for the abandonment of the BSN. These data are also necessary to better understand the pattern of temporary reactivation of the BSN channels across the Holocene and their usage by humans, which can be deduced from historical sources and archaeological data.

Geoarchaeological research at the archaeological site of Mǎgura Gorgana should elucidate the environmental setting Neolithic and Copper Age communities were faced with, when they settled along the Lower Danube Valley, Romania. This should enable a better understanding of human-environment interactions, the natural preconditions of a trading network, as well as the living conditions of the human population during this time. To reach this aim numerous corings were conducted in the study area and the sediments were analysed using a multitude of methods, as total element analyses, determination of carbon and nitrogen isotopes, radiocarbon and OSL-dating and microfaunistical analyses. The present study shows how the interpretation of the results applying a multi-proxy and a ‘regionalisation’ approach reveals the existence and the extent of ‘Lake Gorgana’, a vast paleolake that covered nearly the whole floodplain in the study area during a long phase of the Holocene and, in particular, during the settlement period at Mǎgura Gorgana in the 5th millennium BC. These new findings are of great importance for archaeological concerns but the lake sediments even more represent a valuable geoarchive containing information about e.g. changing lake ecology, paleoclimate, and the human footprint with regard to different spatial and temporal scales.

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.

Loess-palaeosol sequences are most important archives for reconstructing terrestrial palaeoenvironments. However, in the European Mediterranean, these archives are surprisingly scarcely investigated. In southern France, respective sediment-soil archives were last investigated in more detail in the middle of the last century, when major construction works in the region provided access to numerous loess exposures. However, this was before the breakthrough of luminescence-dating as a major chronometric method for the Later Pleistocene. Thus, the loess was poorly dated. Later, Mediterranean loess archives attracted fewer researchers than their central-European counterparts. Reasons for this may be that, compared to the loess belt of temperate Europe, Mediterranean loess deposits are often reworked and mixed with slope deposits. Moreover, palaeosols that developed during climate ameliorations of the last glacial period seem to reflect less pronounced temperature and humidity shifts than those in temperate regions. The most prominent palaeosol developed within the last-glacial loess in the Rhône Valley is a brown palaeosol with large carbonate concretions at its base. However, it is usually severely truncated.We allocated joint research efforts from groups in Germany and France to track last-glacial sedimentation and climate shifts in loess-palaeosol sections along the Rhône Valley, south of the confluence of the River Saone at Lyon. Thereby, optically stimulated luminescence (OSL) dating serves as a vital tool for establishing chronometries for the loess-palaeosol sections in southern France, with first results from the Rhône Valley in Bosq et al. (2018, 2020). We summarize results from two sites that are regarded as key sections for palaeoenvironmental reconstruction along the Rhône Valley as evaluated from inspections during fieldwork, complemented by several smaller sections. Our presentation focusses on challenges met with OSL dating attempts of these Mediterranean archives and first achievements in backing the stratigraphies established by sediment-soil analyses in the field and laboratory by chronometric data.ReferencesBosq, M., Bertran, P., Degeai, J.-P., Kreutzer, S., Queffelec, A., Moine, O., Morin, E., 2018. Last Glacial aeolian landforms and deposits in the Rhône Valley (SE France): Spatial distribution and grain-size characterization. Geomorphology 318, 1–20. doi:10.1016/j.geomorph.2018.06.010Bosq, M., Kreutzer, S., Bertran, P., Degeai, J.-P., Dugas, P., Kadereit, A., Lanos, P., Moine, O., Pfaffner, N., Queffelec, A., Sauer, D., 2020. Chronostratigraphy of two Late Pleistocene loess-palaeosol sequences in the Rhône Valley (southeast France). Quaternary Science Reviews 245, 106473. doi:10.1016/j.quascirev.2020.106473

International audience; A sedimentological and chronostratigraphical investigation was carried out on two loess sections located in the Mediterranean area in southeast France along the Rhône River (Lautagne) and the lower reach of a tributary of the Rhône River (Collias). High-resolution sampling (5–20 cm) for magnetic susceptibility, grain size distribution (including non-parametric end-member modelling), colour reflectance and geochemistry was performed. The chronology was based on luminescence dating of quartz grains and radiocarbon dating of small gastropod shells, coupled with hierarchical Bayesian modelling. The Collias section (~8 m thick) records the whole last climatic cycle. It comprises a thick red basal pedocomplex S1 developed during the Last Interglacial and the Early Glacial, similar to that observed elsewhere in southern and southeastern Europe. Loess deposition occurred during the Lower (L1L2) and the Upper Pleniglacial (L1L1). It was interrupted by soil formation during the Middle Pleniglacial, of which a brown Bwk horizon has been preserved (L1S1). By contrast, the ~5 m thick Lautagne section provides a detailed record of the Upper Pleniglacial. Weakly developed hydromorphic soils are correlated with the Greenland Interstadials GI-4 to GI-2, while the main period of coarse loess sedimentation corresponds to the Greenland Stadials GS-5 to GS-2. At a regional scale, the time of loess deposition ranges between 38.5 ka and 12 ka, with a peak at ~28–24 ka, overlapping with the maximal advance of the Alpine Ice Sheet (AIS). This strongly suggests that regional glacier dynamics was the main driver of loess sedimentation.

There is currently a renewed interest in loess genesis and occurrence in Italy. Well-known loess profiles in northern Italy have been re-examined, and previously unknown loess deposits in central and southern Italy have been reported. This work combines a meta-analysis of published data with new data, presented here for the first time, to provide the state of the art on the spatial distribution, characteristics, genesis, and deposition ages of loess in Italy. A database of 98 soil horizons from 91 soil profiles was created and made available. It stores information on soils formed from loess or containing layers that show admixture of loess. Soil data include the source of information, the topographic, geomorphological and geological setting, kind of parent material and land use, main soil horizon properties as described in the field, soil classification, particle size distribution and chemical data. Loess is reported from almost all regions of Italy. It is generally pedogenized throughout the entire loess body and forms the parent material of deep and complex soil profiles. The thickness of the loess deposits varies from a few decimeters to a few meters; pedogenesis and local reworking partially change the original loess characteristics. In this study, we propose a set of parameters that help recognizing loess in soils: particle size distribution and sorting, geomorphological setting, pedostratigraphic position, shape of the grains under optical and scanning electron microscope (SEM), and soil-micromorphological characteristics. The ages of the loess deposits range between 70 ka BP and 18 ka BP. There are also a number of samples that have been dated to the Holocene. The meta-analysis suggests that climate is not the only driver of loess deposition in Italy; geomorphological instability and human disturbance, as well as the influence of Saharan dust, most likely played major roles, too. This study demonstrates that loess is much more widespread in Italy than previously estimated. Yet, further research on the spatial and temporal distribution of loess deposition across the Mediterranean region is needed to better understand its genesis, sources and trajectories, periods of enhanced loess formation, and the role of loess deposits in ecosystem functioning and resilience.

Feldspar, used for infrared stimulated luminescence (IRSL) dating, is known as a dosimeter which might not completely retain the environmental dose over time, therefore leading to age underestimation. The dose leakage is believed to be caused by non-thermal (anomalous) charge redistribution in the crystal and reflected in an IRSL signal which diminishes with time accordingly. After laboratory irradiation, this signal decline may be monitored by successive IRSL readouts following increasing delay times. Hence, tests of anomalous signal fading are integral steps of IRSL dating procedures applied to feldspar and feldspar-bearing polyminerals. In these measurements IR-stimulation is in most cases preceded by thermal pretreatment (preheating) of the sample. Per common practise, preheating is performed immediately after laboratory irradiation to avoid unwanted electron redistribution assumed to occur if preheating is performed immediately before the delayed IRSL-readout. Here we compile a series of single aliquot regeneration (SAR) measurements questioning this practice. As a result, the fading measurements may possibly reveal post-irradiation afterglow. The results also suggest that data curves resembling anomalous fading may be caused by insufficient control of the readout temperature waning with increasing delay time. The unwanted effects are observed best for IRSL at room-temperature and on luminescence readers with an out-of-date steering software, but they are relevant also for IRSL at elevated temperature and on modern readers, likely including novel post-IR IRSL (pIRIR) protocols. For temperatures as homogeneous as possible during IRSL readout of the (fading) dose, we recommend preheating immediately prior to (delayed) IRSL-readout in order to avoid measurement artefacts either resembling entirely anomalous fading of the IRSL-signal or increasing the true values. It should be noticed that multifold SAR protocol and measurement parameters, like e.g. the type of luminescence reader or the use of N2 flow, may further modify the course of the data values and therefore the amount of the measured signal loss in a particular time interval after laboratory irradiation. Furthermore, calculations of signal fading (g-value) should consider only IRSL-readout after a minimum delay time after laboratory irradiation to avoid including possible post-irradiation afterglow in g-value determination. The measurements compiled in the present study were performed on polymineral fine grains extracted from loess-borne samples from southern Germany and a limnic sample from Mexico. Therefore, the observations are assumed to be not only of local or regional interest but they appear to be of general relevance to SAR fading tests. However, with respect to the likely varying temperatures during IRSL readout of the fading dose administered in the laboratory, the observations are at least partly owed to the promptly measured test dose for normalizing the preceding (fading) dose. This is in contrast to classical multiple aliquot additive (MAA) measurements in which preheating may be replaced by long storage of a sample after laboratory irradiation and in which fading tests may be designed to also correct for possibly (slightly) changing IRSL readout temperatures at different delay times. Thus, the observations are at least partly SAR-immanent.

In this paper we generate chronological constraints through optically stimulated luminescence (OSL) dating on extensive prehistoric stone structures that stretch out in the Arabian Desert and appear as geometric lines, known as the “Works of the Old Men”. Two major types of the “Works” that are common throughout the Arabian Desert are the “wheels” and the more intensively investigated “desert kites”. Here, OSL dating was applied to “wheels” in the Wadi Wisad area, in the eastern badia of Jordan. OSL dating generated ages that fall into the Late Neolithic to Chalcolithic and Early Bronze Age periods. This chronological spectrum is consistent with the well-documented prehistoric activities at the archaeological site of Wisad Pools, also located in the Wadi Wisad area. Spatial analyses of the “Works” in Wadi Wisad and in the Azraq Oasis revealed that: 1) the wheels are organized in clusters, 2) the spatial distribution of the wheels is predetermined by the kites, 3) the kites were most probably created earlier than the wheels in the study areas and 4) a cluster of wheels nearby the Azraq Oasis tentatively demonstrates ranking and, perhaps, tendency for alignment, although this is not the case for the other wheel-clusters studied. Despite the progress toward understanding the chronological and spatial aspects of the wheels, a great deal of research remains to resolve the actual nature of these enigmatic stone structures.

Tell Hujayrat al-Ghuzlan, situated at the northern periphery of modern Aqaba in southern Jordan, is one of the most important sites in Levantine archeology spanning the transitional period from late Chalcolithic to Early Bronze Age times. Numerous stone structures spread out in the surrounding area of the prehistoric settlement were interpreted as the remains of a complex hydro-technical system constructed for water supply of the settlement, agriculture, and craft production. Although construction of the water management system in prehistoric times seems likely, this hypothesis could not be proofed, as archeological evidence is missing and direct dating of the structures is not possible with established dating techniques. But the chronological placement of the irrigation system is essential to evaluate the settlement site appropriately within a wider socioeconomic context. Therefore, here, a feasibility study was carried out to test whether it is possible to date the last exposure of the stone surfaces of the irrigation system to daylight, as expected to occur during construction or repair works. For age determination, the high-resolution optically stimulated luminescence (HR-OSL) dating technique was applied. Five samples were dated, three of them from different hydro-technical components. The HR-OSL ages represent likely man-made as well as non-intentional or natural events. In summary, the results indicate that the water management system was in use in Early Bronze Age times, thus providing a minimum age for the time of construction.

Event-stratigraphical correlations between regional terrestrial sedimentary archives and marine or ice-core records that provide climate history are highly desirable for a deeper understanding of the effects of global climate change. However, such correlations are not simple, as the terrestrial records tend to be floating and fragmentary, and usually show varying sedimentation rates. Therefore, a reliable chronometric framework is a prerequisite for any event stratigraphy involving terrestrial archives. We propose that the age model underlying the event-stratigraphical approach for the eastern European key loess section at Stayky in Ukraine needs revision. Here we explore why it is unlikely that the Middle Pleniglacial Vytachiv Soil developed during Greenland interstadial (GIS) 8, and why the embryonic soils in the upper part of the Upper Pleniglacial part of the loess section most likely post-date the Heinrich 2 event. As a consequence, the revised age-model challenges the earlier suggested correlation of the suite of incipient soils above the Vytachiv Soil with Greenland Interstadials, which was supposed to start with GIS7 but for which matching from after GIS5 seems more likely. The revised chronology suggests that the transition from Middle to Upper Pleniglacial environmental conditions at the eastern European key section occurred during the final phase of marine isotope stage (MIS) 3. Thus, the picture appears to be in accordance with that of the western European key section at Nussloch. This points to a common driver of palaeo-environmental change in both regions, such as early late glacial maximum (LGM) advances of the Arctic ice shield or changes of the North Atlantic circulation and sea-ice distribution associated with changes in the palaeowind field relevant to aeolian loess deposition and soil formation. To test and substantiate the alternative age model, more chronologies for well-stratified loess sections throughout the European loess belt are required.

Riso calibration quartz (RCQ) is used worldwide in luminescence laboratories to calibrate β-sources. RCQ is advantageous because the inherent γ-dose is determined conveniently with a blue light stimulated luminescence (BLSL) single aliquot regeneration (SAR) protocol and dose equivalents (DEs) are highly reproducible with standard errors of the mean of usually

The loess section of Nussloch in southwestern Germany is a key profile for the reconstruction of the terrestrial palaeo-environment of central Europe at the time of the Last Glacial and Interglacial. Recently, the significance of the site for palaeo-environmental and geoarchaeological research increased additionally, with the discovery of unique Palaeolithic cultural remains from anatomically and culturally modern humans that invaded southwestern Germany during the Weichselian (Wurmian) Pleniglacial period. At Nussloch, a chrono-stratigraphical key position is taken by a Middle Pleniglacial Cambisol remain which, under the designation Lohne Soil, serves as an important pedostratigraphic marker horizon for the greater area. Repeatedly, Greenland interstadial (GIS) 8 was suggested as a likely period of soil formation for the Lohne Soil. This interpretation is yet not justified on the basis of published chronometric data. Critical assessment of the data points to a later period of soil formation, likely during GIS7 to GIS5. This conclusion is supported by a new set of radiocarbon ages for the Nussloch site which are presented here for the first time. Consequences of a revised chronology for correlations of Pleniglacial Cryosols below and above the Lohne Soil with Greenland interstadials are discussed. The implications are important for European loess research as the Nussloch section serves as a reference base for loess sections throughout Europe.

This study reveals that in the SE Carpathians terrace development and fluvial incision during the Middle Pleistocene-Holocene are predominantly controlled by tectonic uplift as shown by terrace distributions and uplift amounts and rates. The work focuses on a transect from the internal nappes and Braşov intramontane basin (western domain) to the external nappes and Focşani foredeep basin (eastern domain). New infrared stimulated luminescence ages were obtained and minimum terrace formation ages were determined to derive fluvial incision rates, and thereby, to constrain tectonic uplift. In the eastern domain, non-uniform terrace distributions in adjacent sub-parallel more active Punta and less active Şuşiţa rivers and an eastward migrated fluvial incision from the orogen to the foredeep basin indicate tectonic uplift as dominant control on terrace development. Strath-terraces in the western and eastern domains indicate repeated events of vertical fluvial incision and lateral erosion during the early Middle Pleistocene and late Middle Pleistocene-Holocene, respectively. These events imply successive recurrent disturbances of equilibrium conditions due to pulses of increased tectonic uplift. Fill-terraces in the western domain show that initial aggradation periods were followed by uplift-driven vertical incision during the late Middle-Late Pleistocene. As fill-terraces show a wide-spread development, climatic change and complex response cannot be excluded as contributing factors. Synchronous to terrace development, loess deposition periods during the late Middle-Late Pleistocene and Latest Pleistocene and intercalated episodes of palaeosol formation during the Late Pleistocene imply comparable climatic conditions across the SE Carpathians. Dominant strath-terraces of the eastern domain indicate stronger fluvial incision (~. 240. m) since the late Middle Pleistocene, whereas older strath- and younger dominant fill-terraces of the western domain designate a lower amount (~. 90. m) since the early Middle Pleistocene. Middle Pleistocene-Holocene fluvial incision rates document higher tectonic uplift in the external nappes and lower towards the western intramontane and eastern foredeep basins. © 2013 Elsevier B.V.

Affected by the shifting Intertropical Convergence Zone, Lake Malawi holds an outstanding limnic sediment archive storing palaeo-environmental information of a climatically highly responsive landscape in the East African Rift Valley. Reliable chronological data are essential to interpret the lake-bottom sediments and optically stimulated luminescence (OSL) dating is an important method to build up the chronology. We report on material-property studies and OSL-dating results for polymineral fine grains extracted from piston cores obtained from the northern basin of Lake Malawi during the 1998 campaign of the International Decade of the East African Lakes (IDEAL). OSL-dating is based on a post-IR blue (pIRB) light stimulation single aliquot regeneration (SAR) protocol. Our results support earlier publications demonstrating the general applicability of OSL-dating on Lake Malawi sediments of Holocene and late Pleistocene age. However, the study also shows that dose rate estimations imply major challenges which need to be investigated in more detail to improve future OSL-dating results.

Based on infrared-stimulated luminescence (IRSL) dating of loess-borne sediments, a chronometry of Holocene landscape evolution is established for a representative study site in the early settled Kraichgau area in south-western Germany. The results show that the gently rolling relief is due essentially to soil erosion and colluvial deposition triggered by humans cultivating the loess soils since the onset of agriculture in the Neolithic period. Levelling of relief is accompanied by alterations in soil-type patterns from Haplic Luvisols before the impact of humans, over variably truncated Luvisols with Bt-horizons prevailing at the slope surfaces in the Middle Ages, to Calcaric Regosols characterizing both sites of erosion and accumulation since then. The tremendous changes show that the effects of human activities have been recorded over thousands of years, indicating an early Anthropocene in a geomorphological and pedological sense. Most landscapes are probably more modified by humans than thought at first sight. As the results show, this recognition requires considering that current geomorphological and soil forming processes might work at different frequencies or magnitudes (e.g. by changes of internal system thresholds, such as increased erodibility following the complete erosion of a more resistant Bt-horizon) and/or in a different direction (e.g. accumulation instead of erosion or sediment transport due to slope angles decreased by former deposition of colluvium) than they would in the absence of a human-controlled pre-history.

Lumineszenzdatierung ist eine häufig angewendete Methode zur Altersbestimmung quartärer Materialien, wie z.B. archäologischer Artefakte, vulkanischer Ablagerungen oder von Sedimenten unterschiedlicher Ablagerungsräumen. Das vorliegende Manuskript gibt einen Überblick über die physikalischen Grundlagen der Lumineszenzdatierung, erläutert die notwendigen Prozeduren von der Probennahme bis hin zur Altersberechnung, diskutiert potenzielle Probleme die eine korrekte Altersberechnung beeinträchtigen können und stellt Verfahren vor, mit denen diese Probleme erkannt und beseitigt werden können. Abschließend wird ein kurzer Überblick über die gängigsten Anwendungsgebiete gegeben, von Artefakten bis hin zu verschiedenen Sedimenten, die für Luminszenzdatierung geeignet sind., research

The Atacama Desert is known to be one of the driest places on earth. However, in the study area between Ica and Nasca, South Peru (75–76°W, 14–15°S), palaeoclimate proxies show several semi-arid phases during the Holocene. A more humid period during the early Holocene favoured an open grass land, which allowed the accumulation of desert loess [Eitel, B., Hecht, S., Machtle, B., Schukraft, G., Kadereit, A., Wagner, G., Kromer, B., Unkel, I., Reindel, M., 2005. Geoarchaeological evidence from desert loess in the Nazca-Palpa Region, Southern Peru: palaeoenvironmental changes and their impact on pre-Columbian cultures. Archaeometry, 47, 137–158.]. The Paracas and Nasca cultures existing in that region between the 9th century BC and 7th century AD had propitious conditions to evolve and to settle close to the rivers fed by the monsoonal precipitation in the Cordillera Occidental. Culminating aridity after 600 AD might have caused the collapse of the Nasca civilization. The onset of semi-arid climate towards the end of the Late Intermediate period (∼14th century AD), allowed a reoccupation of the area. Here, we present 14C and OSL data from sediments of river terraces, a debris flow and loess snails (Scutalus sp.), indicating appreciable geomorphic activity between 1390 and 1714 cal AD. This phase is isochronous to the Little Ice Age period on the northern hemisphere and to an increase in the ice accumulation on the Quelccaya glacier in the Peruvian Altiplano [Thompson, L.G., Mosley-Thompson, E., Bolzan, J.F., Koci, B.R., 1985. A 1500-year record of tropical precipitation in ice cores from the quelccaya ice cap, Peru. Science, 229, 971–973.].

In the upper Hoanib River catchment area, northwestern Namibia, fine-grained silty deposits are widespread. Accumulated as river-end deposits they form excellent geomorphological archives of a highly sensitive desert-margin area. Different sedimentary complexes are separated sedimentologically and by luminescence dating. The deposits give evidence of climate oscillations at the eastern margin of the Namib Desert during the past 50,000 years. In northwestern Namibia, the dry conditions of the desert-margin area with less than 200–300 mm mean annual precipitation prevailed at ∼60–40 ka and at ∼34–24 ka when sediment complex-I accumulated. During the Last Glacial Maximum (LGM), fluvial activity and sedimentation were most likely interrupted due to arid conditions. Between ∼12 ka and the Mid-Holocene higher rainfall and runoff led to the aggradation of sediment complex-II. The climate was more humid than before the LGM, but drier than at present. After ∼3 ka runoff increased and the Hoanib River re-eroded the older deposits forming deep channels. A prominent, more sandy and gravely 4 m-terrace in the upper and middle course of the Hoanib River dates to the Little Ice Age (LIA). It is likely that this terrace is genetically linked with the Amspoort Silt formation in the Lower Hoanib valley.

The paper presents proxies from an interdisciplinary geoarchaeological working group. Sediment analyses and geomorphological studies, radiocarbon ages of snail shells and luminescence dating of loess allow a preliminary chronology of the environmental evolution of the eastern Atacama desert, Nazca–Palpa region (southern Peru). Until now, typical desert loess was unknown from the arid western flank of the Andes (southern Peru). The loess points to periods of more humid conditions with open grasslands at the eastern Atacama desert margin in the early and middle Holocene. In the footzone of the Andes, aridification set in before the Paracas Culture (c. 800–200 bc) evolved, but the Cordillera Occidental remained semi-arid. A second push of increasing aridity started at the latest in the Middle Nazca Period (after ad 250). During this time, the Nazca settlement centres moved upstream through the river oasis, following the eastward-shifting desert margin. It is possible that culminating aridity after ad 600 caused the collapse of the Nazca civilization. During the Late Intermediate Period (ad 1000–1400), more humid conditions favoured the massive reoccupation of the eastern Atacama up to a distance of about 40 km from the Pacific coast. Since the 14th and 15th centuries, the Palpa region has again been part of the hyper-arid Atacama. The study shows that in the Nazca–Ica region, the deep cultural changes of Pre-Columbian civilizations were not caused by catastrophic run-off of El Nino events, but by a shifting eastern desert margin due to the changing monsoonal influence.

Detailed geomorphological and chronological investigations of the NW-Namibian Amspoort Silt formation show that the sediments are typical river-end deposits. This type of endoreic sediment, occuring only in desert margin areas, provides valuable information about the palaeo-environment. In the Hoanib valley, the fine-grained deposits have buried riverine trees. Radiocarbon dating of the wood and luminescence dating of the sediments allow a detailed reconstruction of the aggradation processes. Accumulation started ∼10 km downstream of Amspoort around the beginning of the 15th century and ended in the 19th century, some kilometres upstream of Amspoort. This upstream shift of sedimentation during the Little Ice Age was caused by gradually decreasing runoff resulting from aridification of the upper part of the Hoanib river catchment lying east of the Namib desert margin ≥1.200 m a.s.l. The Amspoort Silt terrace is evidence of palaeo-hydrological fluctuations in NW-Namibia. At present, the Hoanib river erodes deeply into the silty deposits, indicating that NW-Namibia receives more monsoonal rainfall today than during the Little Ice Age. However, this contradicts the hypothesis of a (continual) natural aridification of NW-Namibia (Damaraland, Kaokoveld) since the mid-19th century in the course of global climatic change. Rather, deposition and erosion of the Amspoort Silts indicate that landscape degradation in NW-Namibia is primarily anthropogenically induced and most probably not accelerated by a decrease in precipitation.

During the late Pleistocene to mid-Holocene, the Medjerda river system in Mediterranean Tunisia shows events of increased flooding and aggradation of relatively coarse overbank deposits. Geomorphic activity in river systems within this region correlate with aridification of the climate, but not with temperature. The late-Pleistocene to mid-Holocene synthetic profile of the Ghardimaou floodplain (mid-Medjerda river) indicates fluvial activity from 12.4 to 11.8, 6.6 to 6.0 and after 4.8 ka cal. BP. External correlations imply global and regional causes of the late-Pleistocene to mid-Holocene climatic development such as North Atlantic deep-water formation, fluctuations in Saharan humidity and impacts of local Mediterranean weather phenomena. Palaeomagnetic records offer additional opportunities to interpret fluvial activity in river systems, especially for detecting chronological hiatuses in apparently homogeneous sediment sequences.

Die Lumineszenzmethode hat sich seit ihren Anfangen vor 50 Jahren zu einem wichtigen Datierungsverfahren fur quarz- und feldspathaltige archaologische Fundstucke und quartargeologische Ablagerungen entwickelt. Dabei werden Erhitzungs- oder Belichtungsereignisse datiert, bei denen das naturliche Lumineszenzsignal der Minerale zum letzten Mal geloscht wurde. Der zeitliche Anwendungsbereich erstreckt sich bis zu Altern von hunderttausend Jahren. Neuere Entwicklungen - insbesondere ortsaufgeloste Lumineszenzmessung im mikroskopischen Masstab - lassen nicht nur Fortschritte hinsichtlich der Altersgenauigkeit und des Altersbereichs erwarten, sondern eroffnen auch neue Anwendungsmoglichkeiten.

Half a century after the publication of the first Thermoluminescence (TL) ages, the field of Luminescence Dating has reached a level of maturity. Both research and applications from all fields of archaeological science, from archaeological materials to anthropology and geoarchaeology, now routinely employ luminescence dating. The advent of optically stimulated luminescence (OSL) techniques and the potential for exploring a spectrum from mono-minerallic single grains to polymineral multi-aliquots enhanced the applicability, accuracy and the precision of luminescence dating. The present contribution reviews the physical basis, mechanisms and methodological aspects of luminescence dating; discusses advances in instrumentations and facilities, improvements in analytical procedures, and statistical treatment of data along with some examples of applications across continents. The case studies review the dating of heated and solar bleached archaeological material (artefacts, sediments, rocks, rock art and buildings) that cover all periods from Middle Palaeolithic to Medieval Eras and both Old and New World archaeology. They also include interdisciplinary applications that contribute to palaeo-landscape reconstruction.

Half a century after the publication of the first Thermoluminescence (TL) ages, the field of Luminescence Dating has reached a level of maturity. Both research and applications from all fields of archaeological science, from archaeological materials to anthropology and geoarchaeology, now routinely employ luminescence dating. The advent of optically stimulated luminescence (OSL) techniques and the potential for exploring a spectrum from mono-minerallic single grains to polymineral multi-aliquots enhanced the applicability, accuracy and the precision of luminescence dating. The present contribution reviews the physical basis, mechanisms and methodological aspects of luminescence dating; discusses advances in instrumentations and facilities, improvements in analytical procedures, and statistical treatment of data along with some examples of applications across continents. The case studies review the dating of heated and solar bleached archaeological material (artefacts, sediments, rocks, rock art and buildings) that cover all periods from Middle Palaeolithic to Medieval Eras and both Old and New World archaeology. They also include interdisciplinary applications that contribute to palaeo-landscape reconstruction.

Half a century after the publication of the first Thermoluminescence (TL) ages, the field of Luminescence Dating has reached a level of maturity. Both research and applications from all fields of archaeological science, from archaeological materials to anthropology and geoarchaeology, now routinely employ luminescence dating. The advent of optically stimulated luminescence (OSL) techniques and the potential for exploring a spectrum from mono-minerallic single grains to polymineral multi-aliquots enhanced the applicability, accuracy and the precision of luminescence dating. The present contribution reviews the physical basis, mechanisms and methodological aspects of luminescence dating; discusses advances in instrumentations and facilities, improvements in analytical procedures, and statistical treatment of data along with some examples of applications across continents. The case studies review the dating of heated and solar bleached archaeological material (artefacts, sediments, rocks, rock art and buildings) that cover all periods from Middle Palaeolithic to Medieval Eras and both Old and New World archaeology. They also include interdisciplinary applications that contribute to palaeo-landscape reconstruction.

Half a century after the publication of the first Thermoluminescence (TL) ages, the field of Luminescence Dating has reached a level of maturity. Both research and applications from all fields of archaeological science, from archaeological materials to anthropology and geoarchaeology, now routinely employ luminescence dating. The advent of optically stimulated luminescence (OSL) techniques and the potential for exploring a spectrum from mono-minerallic single grains to polymineral multi-aliquots enhanced the applicability, accuracy and the precision of luminescence dating. The present contribution reviews the physical basis, mechanisms and methodological aspects of luminescence dating; discusses advances in instrumentations and facilities, improvements in analytical procedures, and statistical treatment of data along with some examples of applications across continents. The case studies review the dating of heated and solar bleached archaeological material (artefacts, sediments, rocks, rock art and buildings) that cover all periods from Middle Palaeolithic to Medieval Eras and both Old and New World archaeology. They also include interdisciplinary applications that contribute to palaeo-landscape reconstruction.

Half a century after the publication of the first Thermoluminescence (TL) ages, the field of Luminescence Dating has reached a level of maturity. Both research and applications from all fields of archaeological science, from archaeological materials to anthropology and geoarchaeology, now routinely employ luminescence dating. The advent of optically stimulated luminescence (OSL) techniques and the potential for exploring a spectrum from mono-minerallic single grains to polymineral multi-aliquots enhanced the applicability, accuracy and the precision of luminescence dating. The present contribution reviews the physical basis, mechanisms and methodological aspects of luminescence dating; discusses advances in instrumentations and facilities, improvements in analytical procedures, and statistical treatment of data along with some examples of applications across continents. The case studies review the dating of heated and solar bleached archaeological material (artefacts, sediments, rocks, rock art and buildings) that cover all periods from Middle Palaeolithic to Medieval Eras and both Old and New World archaeology. They also include interdisciplinary applications that contribute to palaeo-landscape reconstruction.

Optically stimulated luminescence (OSL) dating is essential to establish a chronometry for the reconstruction of the history of the landscape development in the Palpa-Nasca region. To achieve this, we apply both traditional techniques based on the preparation of disturbed samples and a novel, spatially resolved HR-OSL technique used for samples with their original mineral-grain structure (Greilich and Wagner, this volume). The new technique offers a great potential to access new types of sediment archives relevant to geomorphological and geoarchaeological studies.

The aim of this geoarchaeological pilot study is to investigate to what extent geochemical and geochronometric techniques can be used in order to decipher the landscape development around Hisarlik hill and to detect events that left traces in the sedimentary archives encircling the Troia settlement area. Three drill holes close to and one further away from the hill were sunk up to 23 m below ground level into the sediments at today’s footslope and alluvial plain positions. The stratigraphy and sedimentology of the cores were investigated. In addition, geochemical analyses as well as luminescence (OSL) and 14C dating were carried out on samples taken from the drill cores. Detailed stratigraphic and geochemical analyses are not only relevant for landscape reconstruction, but also for identifying the facies suitable for luminescence dating. Hill-slope sediments and some alluvial deposits are considered to yield reliable ages. Major landscape changes by sediment accumulation occurred during the Troia VI and IX periods.

International audience; The cross-bleaching behaviour of automated Risø TL/OSL (DA-12, DA-15, DA-20) luminescence readers is investigated. By design, up to 24 or 48 aliquots can be stored on a carousel in a single measurement chamber. Due to this construction, irradiation or illumination on one sample may affect the adjacent position resulting in systematic errors. Previously reported for blue LEDs, such cross-talk (cross-bleaching/illumination) has never been quantified explicitly for the infrared (IR) LEDs, although they are intensively used in IRSL measurements of e.g. feldspar and polymineral samples. In IRSL measurements of feldspar or polymineral samples it is important to keep the time constant between the (midpoint of the) irradiation and the subsequent read out to avoid the malign effects of anomalous fading in laboratory constructed dose response curves. This may be achieved by running all measurements for equivalent dose estimation on a single sample before moving to a subsequent sample (e.g. by using the " run 1 at a time " option in the Risø sequence editor). However, if the measurement sequence is not designed carefully, then using this option may result in a significant depletion of the natural signal on subsequent samples. Here we investigate the size of this reduction due to cross-bleaching from the IR diodes and quantify the cross-bleaching for 10 different Risø TL/OSL readers produced between 1994 and 2011. We find that cross-bleaching from the IR diodes is worse than from the blue diodes. Using the " run 1 at the time " option can result in significant dose underestimation (1) if the sequence is not split into different sets, or (2) if samples are not placed on every 2 nd position. In addition, a newly designed flange for the optical unit of the TL/OSL reader is presented which appears to reduce cross-bleaching significantly.