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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.

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.

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.

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.

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.].

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.