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The sites of Hawelti–Melazo in the Tigray region of the northern Ethiopian Highlands is an archaeological hotspot related to the D'mt kingdom (ca. 800–400 BCE). The existence of several monumental buildings, which have been excavated since the 1950s, underline the importance of this area in the Ethio-Sabaean period. We investigated the geomorphological and geological characteristics of the site and its surroundings and carried out sedimentological analyses, as well as direct (luminescence) and indirect (radiocarbon) sediment dating, to reconstruct the palaeoenvironmental conditions, which we integrated into the wider context of Tigray. Luminescence dating of feldspar grains from the May Agazin catchment indicate enhanced fluvial activity in the late Pleistocene, likely connected to the re-occurring monsoon after the Last Glacial Maximum (LGM). The abundance of trap basalt on the Melazo plateau, which provides the basis for the development of fertile soils, and the presumably higher groundwater level during the Ethio-Sabaean Period, provided favourable settlement conditions. The peninsula-like shape of the Melazo plateau was easily accessible only from the east and northeast, while relatively steep scarps enclose the other edges of the plateau. This adds a possible natural protective function to this site.

Glaciers preserve climate variations in their geological and geomorphological records, which makes them prime candidates for climate reconstructions. Investigating the glacier–climate system over the past millennia is particularly relevant first because the amplitude and frequency of natural climate variability during the Holocene provides the climatic context against which modern, human-induced climate change must be assessed. Second, the transition from the last glacial to the current interglacial promises important insights into the climate system during warming, which is of particular interest with respect to ongoing climate change. Evidence of stable ice margin positions that record cooling during the past 12 kyr are preserved in two glaciated valleys of the Silvretta Massif in the eastern European Alps, the Jamtal (JAM) and the Laraintal (LAR). We mapped and dated moraines in these catchments including historical ridges using beryllium-10 surface exposure dating (10Be SED) techniques and correlate resulting moraine formation intervals with climate proxy records to evaluate the spatial and temporal scale of these cold phases. The new geochronologies indicate the formation of moraines during the early Holocene (EH), ca. 11.0 ± 0.7 ka (n = 19). Boulder ages along historical moraines (n = 6) suggest at least two glacier advances during the Little Ice Age (LIA; ca. 1250–1850 CE) around 1300 CE and in the second half of the 18th century. An earlier advance to the same position may have occurred around 500 CE. The Jamtal and Laraintal moraine chronologies provide evidence that millennial-scale EH warming was superimposed by centennial-scale cooling. The timing of EH moraine formation coincides with brief temperature drops identified in local and regional paleoproxy records, most prominently with the Preboreal Oscillation (PBO) and is consistent with moraine deposition in other catchments in the European Alps and in the Arctic region. This consistency points to cooling beyond the local scale and therefore a regional or even hemispheric climate driver. Freshwater input sourced from the Laurentide Ice Sheet (LIS), which changed circulation patterns in the North Atlantic, is a plausible explanation for EH cooling and moraine formation in the Nordic region and in Europe.

Unanswered questions about the glacier and climate history preceding the global Last Glacial Maximum (LGM) in the southern temperate latitudes remain. The Marine Isotope Stage (MIS) 3 is normally understood as a global interstadial period; nonetheless its climate was punctuated by conspicuous variability, and its signature has not been resolved beyond the polar realms. In this paper, we compile a 10Be depth profile, single grain infrared (IR) stimulated luminescence dating and 14C samples to derive a new glacier record for the principal outwash plain complex, deposited by the western Patagonian Ice Sheet (PIS) during the last glacial period (Llanquihue Glaciation) on the Isla de Chiloé, southern Chile (42∘ S). In this region, the Golfo de Corcovado Ice Lobe left a distinct geomorphic and stratigraphic imprint, suitable for reconstructing former ice dynamics and timing of past climate change. Our data indicate that maximum glaciation occurred by 57.8±4.7 ka without reaching the Pacific Ocean coast. Ice readavanced and buttressed against the eastern side of the Cordillera de la Costa again by 26.0±2.9 ka. Our data further support the notion of a large ice extent during parts of the MIS 3 in Patagonia and New Zealand but appear to contradict near contemporaneous interstadial evidence in the southern midlatitudes, including Chiloé. We propose that the PIS expanded to its full-glacial Llanquihue moraines, recording a rapid response of southern mountain glaciers to the millennial-scale climate stadials that punctuated the MIS 3 at the poles and elsewhere.

We propose a new concept of the Weichselian ice dynamics in the south-western sector of the Baltic Sea depression. The review of existing geochronological data from Germany, Denmark and southernmost Sweden in combination with new optically stimulated luminescence (OSL) data from the German Oder Lobe area is the basis for a reassessment and an improvement of previous ice dynamic models. Factors like the pre-existing topography, glaciotectonic features and the occurrence of till beds and inter-till deposits of varying origin are also taken into consideration for our process-based reconstruction of the sedimentary environments close to the ice margin and hence the ice dynamics of the Scandinavian Ice Sheet (SIS). During the early MIS 3 (marine isotope stage), the late MIS 3 and MIS 2, the SIS advanced into present-day terrestrial areas around the south-western Baltic Sea Basin. The first ice advance during the warming phase in early MIS 3 is poorly documented as the Ellund–Warnow Advance in Germany but may be correlated with the numerically dated Ristinge Advance in Denmark and Sweden. The late MIS 3 advance in contrast is reliably documented. It shaped the landforms of the Brandenburg Advance and the maximum Weichselian ice extent in the Oder Lobe area in north-eastern Germany and occurred contemporaneously with the Klintholm Advance in southern Sweden and Denmark. The lack of a corresponding till in various cliff profiles along the Baltic Sea coastline between southern Schleswig-Holstein and the island of Rügen can be explained by the distinct lobate structure of this ice advance, which was strongly guided by the pre-existing low-lying topography. We propose the horst of Bornholm, Denmark, acting as an ice divide, with ice-dammed lakes existing on the lee side between two glacier lobes. This lobate structure had not been considered in previous conceptual models, which led to seemingly conflicting chronological and stratigraphical interpretations. Our introduction of the lobate structure for the first time resolves these contradictions and integrates the data in a coherent model. The dynamics of the MIS 2 readvance to the Last Glacial Maximum (LGM) extent were clearly different to the previous advance and were most likely characterized by a more uniformly advancing ice front with a less lobate structure which also overrode the horst of Bornholm and the island of Rügen. This advance reached the maximum Weichselian ice extent in some parts of the south-western SIS, but, in the Oder Lobe area, it is proven to have terminated at a lesser extent than the early MIS 3 advance, but it did shape the most prominent morphological landform record of the last glacial cycle. In order to advance the reconstruction of Weichselian ice dynamics in the future, we strongly suggest using both an MIS-based terminology and a process-based approach in the interpretation of geochronological data to live up to the dynamic nature of continental ice sheets.

Intraplate regions characterized by low rates of seismicity are challenging for seismic hazard assessment, mainly for two reasons. Firstly, evaluation of historic earthquake catalogues may not reveal all active faults that contribute to regional seismic hazard. Secondly, slip rate determination is limited by sparse geomorphic preservation of slowly moving faults. In the Vienna Basin (Austria), moderate historical seismicity (Imax, obs ∕ Mmax, obs = 8∕5.2) concentrates along the left-lateral strike-slip Vienna Basin Transfer Fault (VBTF). In contrast, several normal faults branching out from the VBTF show neither historical nor instrumental earthquake records, although geomorphological data indicate Quaternary displacement along those faults. Here, located about 15 km outside of Vienna, the Austrian capital, we present a palaeoseismological dataset of three trenches that cross one of these splay faults, the Markgrafneusiedl Fault (MF), in order to evaluate its seismic potential. Comparing the observations of the different trenches, we found evidence for five to six surface-breaking earthquakes during the last 120 kyr, with the youngest event occurring at around 14 ka. The derived surface displacements lead to magnitude estimates ranging between 6.2 ± 0.5 and 6.8 ± 0.4. Data can be interpreted by two possible slip models, with slip model 1 showing more regular recurrence intervals of about 20–25 kyr between the earthquakes with M ≥ 6.5 and slip model 2 indicating that such earthquakes cluster in two time intervals in the last 120 kyr. Direct correlation between trenches favours slip model 2 as the more plausible option. Trench observations also show that structural and sedimentological records of strong earthquakes with small surface offset have only low preservation potential. Therefore, the earthquake frequency for magnitudes between 6 and 6.5 cannot be constrained by the trenching records. Vertical slip rates of 0.02–0.05 mm a−1 derived from the trenches compare well to geomorphically derived slip rates of 0.02–0.09 mm a−1. Magnitude estimates from fault dimensions suggest that the largest earthquakes observed in the trenches activated the entire fault surface of the MF including the basal detachment that links the normal fault with the VBTF. The most important implications of these palaeoseismological results for seismic hazard assessment are as follows. (1) The MF is an active seismic source, capable of rupturing the surface despite the lack of historical earthquakes. (2) The MF is kinematically and geologically equivalent to a number of other splay faults of the VBTF. It is reasonable to assume that these faults are potential sources of large earthquakes as well. The frequency of strong earthquakes near Vienna is therefore expected to be significantly higher than the earthquake frequency reconstructed for the MF alone. (3) Although rare events, the potential for earthquake magnitudes equal or greater than M = 7.0 in the Vienna Basin should be considered in seismic hazard studies.

Bisher basierte die Chronologie des Weichsel-Pleniglazials in Nord-Ost-Deutschland im Wesentlichen auf morphostratigraphischen Befunden und Radiokohlenstoffdatierungen organischer Sedimente aus dem Liegenden glazigener Ablagerungen. Im Laufe der letzen Jahre kamen im Rahmen verschiedener Studien Datierungsmethoden zum Einsatz, mit deren Hilfe es möglich war, die glazigenen Sedimente direkt zu datieren: Optisch Stimulierte Lumineszenz (OSL) von glazifluvialen Sedimenten und Oberflächen-Expositionsdatierungen (surface exposure dating, SED) von erratischen Blöcken. Wir fassen die Ergebnisse dieser Studien zusammen und bewerten sie auf der Grundlage eines prozessbasierten Interpretationsschemas neu, um somit eine neue Chronologie für die weichselzeitlichen Haupteisrandlagen in Nord-Ost-Deutschland vorstellen zu können. Auf der Grundlage der verfügbaren Daten lassen sich zwei Phasen während des letzten Glazials nachweisen, wobei die Brandenburger Phase einen Eisvorstoß im späten Marinen Isotopenstadium (MIS) 3 bis frühen MIS 2 repräsentiert, während die Pommersche Phase einen Eisvorstoß widerspiegelt, der seinen Maximalstand um ~20 ka erreichte. Hinsichtlich der endgültigen Stabilisierung der Geländeoberflächen nach der initialen Eisfreiwerdung zeigt sich eine hohe Abhängigkeit von Phasen aktiver Transformation unter periglazialen Bedingungen. Erste Ergebnisse numerischer Datierungen deuten auf eine solche Aktivitätsphase um ~15 ka hin.

In order to reassess the geomorphologic development of the Rangsdorf lake area a strategy combining the technical potentials of a GIS with geomorphologic fieldwork was developed. As a basis for the GIS-analysis topographic and geologic maps of different age were digitally processed. The main focus was on updating the Prussian Geological Maps from the 19th century. After the combination with a specially developed DEM, a preliminary model of the geomorphologic development was constructed: In Weichselian time subglacial meltwater deeply incised into a push-morainic area of Saalian age, creating a braided system of meltwater channels. In the course of the meltdown of the ice subaeric meltwater runoff and with it accumulational processes set in. Large masses of dead ice were buried especially within the overdeepened meltwater channels. Later, as the dead ice started to melt a broad lake system evolved. Dunes were formed in lateglacial time. The Holocene was dominated by accumulative processes which caused a relative levelling of the relief. In the course of the verification of that model by fieldwork it became clear that the Saalian formation is of even greater meaning than assumed before: Not only full forms but also channels originate from Saalian time. The predominance of glacially-erosive processes on the till plains and glacially-accumulative processes within the meltwater channels throughout the Weichselian Glaciation was supported by the field evidence.

During COP 21 in Paris 2015, several states and organizations agreed on the "4/1000" initiative for food security and climate. This initiative aims to increase world's soil organic carbon (SOC) stocks by 4‰ annually. The influence of soil development status on SOC dynamics is very important but usually not considered in studies. We analyse SOC accumulation under forest, grassland and cropping systems along a soil age gradient (10-17,000years) to show the influence of soil development status on SOC increase. SOC stocks (0-40cm) and accumulation rates along a chronosequence in alluvial soils of the Danube River in the Marchfeld (eastern Austria) were analysed. The analysed Fluvisols and Chernozems have been used as forest, grassland and cropland for decades or hundreds of years. The results showed that there is a fast build-up of OC stocks (0-40cm) in young soils with accumulation of ~1.3tha -1 a -1 OC in the first 100years and ~0.5tha -1 a -1 OC between 100 and 350years almost independent of land use. Chernozems with a sediment deposition age older than 5.000years have an accumulation rate<0.01tOCha -1 a -1 (0-40cm). Radiocarbon dating showed that the topsoil (0-10cm) consists mainly of ">modern" and "modern" carbon indicating a fast carbon cycling. Carbon in subsoil is less exposed to decomposition and OC can be stored at long-time scales in the subsoil ( 14 C age of 3670±35 BP). In view of the '4/1000' initiative, soils with constant carbon input (forest & grassland) fulfil the intended 4‰ growth rate of SOC stocks only in the first 60years of soil development. We proclaim that under the present climate in Central Europe, the increase of SOC stocks in soil is strongly affected by the state of soil development., (Copyright © 2018 Elsevier B.V. All rights reserved.)

During the penultimate glaciation vast areas of the Alps were glaciated, with piedmont glaciers protruding into the foreland. In the easternmost part of the northward draining valleys of the Alps, the glaciers did not reach the foreland, but formed valley glaciers confined by the mountainous terrain. This also applies to the Ybbs valley, where samples for luminescence dating out of glaciofluvial gravel accumulations were taken at three locations along the present day river course. In a highly dynamic depositional environment, such as a glacier-fed river system, incomplete resetting of the luminescence signal is possible, in particular when transport distances are short. In such cases, quartz usually is the preferred mineral over feldspar, especially if dose rates are low and may theoretically allow obtaining quartz ages beyond 150 ka. Because previous research has shown, and as corroborated within this study, quartz from the research area exhibits analytical problems in the high age range. Therefore luminescence properties of coarse grain (100-200 μm) quartz and in addition K-rich feldspar were investigated with the aim to reconstruct the chronology of the glacial processes within the Ybbs catchment area. Issues of incomplete bleaching were pIRIR225 encountered and addressed by comparing quartz OSL, fading corrected K feldspar IR50 and pIRIR225 to identify reliable ages. Depositional ages based on quartz OSL and feldspar pIRIR225 signals revealed deposition of ice marginal kame terraces and glaciofluvial foreland terraces during late to middle MIS 6. In combination with results from previous studies, we could reconstruct the valley evolution during the Riss glaciation. Newly gained luminescence ages of the deglaciation in the easternmost Alps coincide with OSL dated deglaciation events in the Western Alps, indicating that climatic change along the north side of the Alps happened simultaneously.

Research has shown that people prefer supporting to conflicting information when making decisions. Whether this biased information search also occurs in group decision making was examined in three experiments. Experiment 1 indicated that groups as well as individuals prefer supporting information and that the strength of this bias depends on the distribution of the group members' initial decision preferences. The more group members had chosen the same alternative prior to the group discussion (group homogeneity), the more strongly the group preferred information supporting that alternative. Experiment 2 replicated these results with managers. Experiment 3 showed that the differences between homogeneous and heterogeneous groups reflect group-level processes. Higher commitment and confidence in homogeneous groups mediated this effect. Functional and dysfunctional aspects of biased information seeking in group decision making are discussed.