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The depocenters of epicontinental basins usually comprise relatively continuous depositional records, and these can be used in the determination of sediment routing and paleogeographic changes via a set of various geophysical, sedimentological, biostratigraphic and geochronological approaches. although the margins of such basins will have a major role as constraints for that sediment routing, their depositional records are typically scarce and incomplete, posing a common challenge in terms of gaining information about them. the present study focuses on the upper Miocene succession present in the Malé Karpaty Mts., a pre-cenozoic horst dividing the vienna and Danube basins (central Europe). The data gained by facies analysis, biostratigraphy, shallow seismic survey, authigenic 10Be/9Be dating and correlation of archival borehole profiles reveals, that the succession under consideration represents a record of the lake Pannon transgression, which appeared in the study area at ~10.9-10.6 ma. The subaerially exposed granitic massif and middle miocene successions sourced a shoal water delta, which intercalated with waveinduced dunes and open lacustrine muds in brackish sublittoral to marginal littoral environments. the granitic massif was probably also exposed later, during the regression of lake Pannon at ~10.2-10.0 ma, as a result of the progradation of the paleo-Danube delta from the vienna Basin southeastwards. The depositional record of the regressive sequence was documented and dated in well-cores from the nearby Danube Basin margin. The documented scenario of transgression preceding the overall regression of the paleo-danube delta system by a relatively short period is characteristic of several other localities across the Pannonian Basin system, and may imply that the progradation of depositional system caused a base-level rise on account of sediment loading-induced subsidence. [ABSTRACT FROM AUTHOR]

The growing number of studies based on data provided by the accelerator mass spectrometry (AMS) technique from increasingly diverse matrices implies that developing very effective and reproducible sample processing techniques is crucial to meet the demand generated. After being dissolved, the isolation of the cosmogenic nuclide to be measured and its chemical purification imply complex processes throughout successive stages The presented automatic system was designed to perform the final steps of the 10Be and 26Al chemical extraction protocol from natural matrices (sediments, pure mineral phases,...), previously purified, decontaminated and dissolved in the case of in situ-produced cosmogenic nuclides, or leached or dissolved in the case of meteoric cosmogenic nuclides. Driven by Labview software, the developed automatic system, in addition to freeing the operator from tedious tasks, allows reproducibly processing simultaneously up to eight samples of different volumes in roughly 40 min. This article presents the design of the automated extraction bench and its performance based on the recovery efficiency of the stable element and the reproducibility of the measurements of the cosmogenic nuclide concentrations by AMS. [ABSTRACT FROM AUTHOR]

The recent tectonics of the arid northern Chile Andean western forearc is characterized by trench‐parallel normal faults within the Atacama Fault System (AFS). Since the 1995‐Mw 8.1 Antofagasta earthquake, the mechanism driving this recent and localized extension is considered to be associated with the seismic cycle within the subduction zone. Analyzing morphotectonic patterns along these faults allows examining the seismic potential associated with the subduction zone. Using field Digital Elevation Models and in situ‐produced cosmogenic 10Be, we determined a 0.2 mm/a long‐term slip rate along the Mejillones Fault, one of the most prominent structures within the AFS. This result suggests that the AFS corresponds to slow slip rate faults despite the rapid subduction context. However, the size of coseismic slips observed along the AFS faults suggests that larger subduction earthquakes (Mw > 8.1) may occur episodically in the area. [ABSTRACT FROM AUTHOR]

Bedrock outcrops punctuating regolith-covered surfaces in the summit/upper slope and hillside positions (tors and crags) have long been a subject of inquiry in geomorphology for their evolutionary trajectories and now also as valuable geoheritage sites. Methodological advances in research, such as DTM-based geomorphological analysis and terrestrial cosmogenic nuclide inventories, create new perspectives to decipher the spatial and temporal context of tor emergence and decay. The shape, structural controls, 10Be inventories and relation to surrounding medium-scale landforms were studied at thirteen conspicuous bedrock outcrops developed in metamorphic and sedimentary lithologies in the Bohemian-Moravian Highland, Czechia. The shapes of studied bedrock outcrops indicate significant litho-structural controls. The general outline is mainly governed by (sub)vertical joints, whereas the inclination of foliation or bedding planes dictates summit and cliff morphology. Some of the tors described in this study developed in exceptionally densely foliated and jointed gneiss, which does not comply with the generally accepted view of tors as massive rock compartments resisting weathering. A series of rock hardness measurements performed at three gneissic tors using Schmidt hammer show statistically significant within-tor variability of R-values, indicating different exposure times to subaerial weathering. The complexity of landform assemblages, within which studied tors/crags are developed, varies from isolated bedrock outcrops surrounded by smooth slopes covered with debris-rich soils to outcrops accompanied by low rock cliffs, debris-covered steps, slope benches, boulder fields and isolated large blocks. The 10Be inventories reveal ages mostly from the Late Pleistocene and rarely from the Holocene. Summit/upper slope tors and hillside crags show considerable variability in maximum denudation rates ranging from 6.4 ± 0.2 to 105.6 ± 4.8 m/Ma. Paired samples from the summits and cliffs of eight outcrops indicate three possible post-emergence evolutionary scenarios with summit downwearing while keeping the outcrop outline, balanced cliff and summit degradation rate, and backwearing as the dominant degradation process. [Display omitted] • Terrestrial cosmogenic nuclide inventories determined on tors and crags, Czechia. • Tor and crag surfaces show Late Pleistocene to Holocene apparent exposure ages. • The variety of medium-scale landforms accompanies tors and crags. • Rock hardness (R values) show significant variability within individual tors. • Post-emergence evolutionary scenarios differ among the investigated tors. [ABSTRACT FROM AUTHOR]

Abstract Seismically active fault zones receive a great deal of attention due to their potential for quantification of seismic hazards. Zones with low slip rates pose a challenge, however, since their poor topographic expression is related to difficulties in the quantification of fault movement. This study focuses on the Dobrá Voda Depression, an area with the highest level of seismic activity in the Western Carpathians. The Quaternary tectono-sedimentary evolution of the small intramontane basin was investigated with the use of facies analysis of cores, dated with the use of cosmogenic nuclide depth profiles (10Be, 26Al and 36Cl), together with 26Al/10Be burial dating and radiocarbon dating. A set of archived boreholes and geoelectric survey data was used for the correlation of results with those from new boreholes across the depression. Four facies associations were distinguished: (FA1) Colluvial deposits that comprise subaerial debris flows and mudflows; (FA2) Fluvial deposits with high sediment supply: accommodation ratio, composed mostly of sandy-gravelly channel fill facies; (FA3) Fluvial deposits with low sediment supply: accommodation ratio, consisting mostly of floodplain muds, overbank heterolithic facies and minor sandy-gravelly channel fills; and (FA4) Swamp deposits, which are mostly made up of peat. Geochronological results suggest that the studied part of FA3 was deposited before 1.0 Ma due to a rise in the base level following a major incision event. Overbank-dominated deposits of FA3 covered an incision surface, resulted in a difference of ca. 65 m of elevation of these strata, which represents the minimal thickness of FA3. The second phase of incision was related to reactivation of Miocene normal faults resulting in further topographic differentiation. The initiation of fault activity is recorded by the deposition of colluvial FA1 before ca. 250 ka. FA2 accumulated between ca. 160 and 100 ka, mostly at the toes of slopes bounding the fault scarps on the basin margins. The last documented phase of evolution represents an increase of accommodation, which was connected to the deposition of Holocene peat in swamps as well as floodplain muds of FA4 above FA2. The observed settings imply that variation between incision and accumulation in a scale of hundreds of thousands of years is characteristic for low relief tectonically active zones. The presented research demonstrates the significance of sedimentological analysis for reconstruction of tectonic evolution in areas with low slip rate activity. Highlights • Depth profile exposure dating of 10Be, 26Al and 36Cl applied together with 14C dating. • Accumulation in the area was interrupted by two phases of incision at >1 Ma and 250–100 ka. • Reactivation of normal faults and topographic differentiation during 250–100 ka. • Overbank/channel fill ratio and alluvial/colluvial deposition changes driven by base level shifts. • Accumulation-incision alteration characteristic for moderate relief tectonically active zones. [ABSTRACT FROM AUTHOR]

Abstract The Danube Basin, located in the junction of the Eastern Alps and Western Carpathians, comprises up to 600 m thick alluvial succession, which was previously assigned to the Quaternary without geochronological constraints. The internal stratigraphy and timing of the succession remained unknown, although it has potential to provide an important record of geological evolution of the region. The present study involves 26Al/10Be burial dating of 17 samples from wells along with facies correlation from the NW margin towards the basin centre, with the purpose of recovering the Pliocene-Quaternary depositional archive. Obtained ages ranging from 0.58 ± 0.06 to 3.39 ± 2.11 Ma allow for four separate members to be distinguished. The lowermost Kolárovo Fm. with inferred depositional age of ~5–2.6 Ma shows lateral variability with gradual shift of channel fills composed of sands and gravelly sands across the floodplain/pond facies from NW to SE. An abrupt increase of sediment supply:accommodation ratio was observed at ~2.6 Ma, and led to the dominance of amalgamated gravelly channel fills in the centre of the basin. Another sharp increase of sediment supply was observed at ~1.2 Ma, reflected in a brief period of dominance of gravelly channel fill facies across the basin. This highly supplied environment then gradually occupied the whole basin after ~0.9 Ma. Petrographic study implies a distant provenance for the period ~5.0–2.6 Ma. The subsequent interval is characterised by sediment sourcing from uplifting mountains of the Western Carpathians on the margins of the Danube Basin, drained by the Váh River. A notable change appeared after ~0.9 Ma, when the Eastern Alpine provenance of clasts brought by the Danube River prevailed. Based on a review of existing data about regional tectonics and climate, the changes in this depositional record are interpreted as an interplay of climate changes (~2.6 Ma and ~1.2 Ma) and local vertical movements affecting both sediment input and drainage network patterns. The accommodation space was formed without contribution of fault activity according to the observed settings. A noteworthy observation is time transgressive shift of facies boundaries in the Pliocene-Quaternary succession. Graphical abstract Unlabelled Image Highlights • Continual late Pliocene to Quaternary accumulation in highly supplied "bypass" settings • Time-transgressive character of facies change from NW to SE across the basin. • Climatically triggered abrupt increase of sediment supply:accommodation ratio at ~2.6 Ma and ~1.2 Ma • Gradual increase in sediment supply:accommodation ratio due to local uplifts in ~5.0–2.6 and ~1.2–0.0 Ma • W. Carpathian provenance (Váh River) was replaced by the E. Alpine (Danube River) after ~0.9 Ma. [ABSTRACT FROM AUTHOR]

The purpose of the study was to investigate, whether the newly developed laboratory at the Dept. of Geology and Palaeontology (Comenius University in Bratislava, Slovakia) is suitable for processing of samples for authigenic 10Be/9Be dating method. The approach was validated on reprocessing of four samples, which were previously analysed at CEREGE (Aix-en-Provence, France). The samples underwent leaching and resin chemistry. Each sample was triplicated with the preparation of a blank sample. Processed samples were sent to CEREGE for isotopic measurements, which provided 15 values of 10Be/9Be ratio. The obtained values showed a good consistency for each sample, although two subsamples appeared as outliers (one of which was original). Analytical uncertainties are comparable to the original measurements, difference is below 1.5 %. Processing blanks yielded stable values at least three orders of magnitude lower than measured subsample 10Be/9Be ratios, what imply a good workflow conditions. These tests revealed that the new laboratory is suitable for processing samples for authigenic 10Be/9Be dating method. [ABSTRACT FROM AUTHOR]

Authigenic 10 Be/ 9 Be dating method was applied to lacustrine, deltaic and alluvial sequences of the northern Danube Basin (Pannonian Basin System), to bridge the insufficiency of geochronological data for the Late Miocene to Pliocene period. The measurements of 51 samples (both lacustrine and floodplain), ranging from 11.6 to 0.95 Ma are consistent with the existing magnetostratigraphic and biostratigraphic data standing mainly on the evolution degree of endemic mollusk fauna, mammals and dinocysts. This agreement confirms our assumption that the incoming beryllium fluxes remained constant over the studied time period and thus that the two initial 10 Be/ 9 Be ratios determined in actual Holocene/Late Pleistocene sediments (lacustrine and floodplain) are valid for these environments. The obtained ages indicate gradual progradation of the deltaic depositional systems across the Danube Basin with a clear time-transgressional character, replacing basin floor and shelfal environments. Deltaic sedimentation occurred firstly in the north at foothills of the Western Carpathians from 11.0 Ma, and changed to the alluvial environment after 10.5 Ma. At the same time (~ 10.5 Ma), the paleo-Danube deltaic system draining the Eastern Alps entered the study area from the Vienna Basin situated on the West. Later, the deltaic systems were merged in the central part of the basin and reached its southeastern margin at ~ 9.4 Ma. Regression of the Lake Pannon from the southernmost part of the study area is evidenced after 8.7 Ma. Alluvial deposition of meandering rivers lasting until 6.0–5.0 Ma followed and was interrupted by the early Pliocene basin inversion. Sedimentation of braided streams took place during the late Pliocene and Pleistocene, reflecting uplift of mountains surrounding the basin margins. This study documents the powerful potential of the authigenic 10 Be/ 9 Be dating method and its reliability in a basin with complicated tectonic and sedimentary history. It demonstrates that this method can effectively be applied to lacustrine and floodplain deposits and to samples from outcrops as well as boreholes. [ABSTRACT FROM AUTHOR]

The terrace sequence of the Hungarian part of the Danube valley preserves a record of varying tectonic uplift rates along the river course and throughout several climate stages. To establish the chronology of formation of these terraces, two different dating methods were used on alluvial terraces: exposure age dating using in situ produced cosmogenic 10 Be and luminescence dating. Using Monte Carlo approach to model the denudation rate-corrected exposure ages, in situ produced cosmogenic 10 Be samples originated from vertical depth profiles enabled the determination of both the exposure time and the denudation rate. Post-IR IRSL measurements were carried out on K-feldspar samples to obtain the ages of sedimentation. The highest terrace horizon remnants of the study area provided a best estimate erosion-corrected minimum 10 Be exposure age of >700 ka. We propose that the abandonment of the highest terrace of the Hungarian Danube valley was triggered by the combined effect of the beginning tectonic uplift and the onset of major continental glaciations of Quaternary age (around MIS 22). For the lower terraces it was possible to reveal close correlation with MIS stages using IRSL ages. The new chronology enabled the distinction of tIIb (∼90 ka; MIS 5b–c) and tIIIa (∼140 ka; MIS 6) in the study area. Surface denudation rates were well constrained by the cosmogenic 10 Be depth profiles between 5.8 m/Ma and 10.0 m/Ma for all terraces. The calculated maximum incision rates of the Danube relevant for the above determined >700 ka time span were increasing from west (<0.06 mm/a) to east (<0.13 mm/a), toward the more elevated Transdanubian Range. Late Pleistocene incision rates derived from the age of the low terraces (∼0.13–0.15 mm/a) may suggest a slight acceleration of uplift towards present. [ABSTRACT FROM AUTHOR]

Sequences of alluvial fill-terraces record the long-term variation of fluvial transport regimes in response to Quaternary climatic changes. Through a production of increasingly precise chronologies, the broadening range of sediment dating methods in recent years has improved our understanding of correlations between alluvial dynamics and external forcing mechanisms. However, results in this field have mostly focused on periglacial and other mid-latitude settings. These may not readily apply to glaciofluvial environments, where alluvial regimes are narrowly dependent on the behavior of the adjacent ice-field. Here we constrain the ages of three glaciofluvial fill terraces based on five vertical 10 Be age profiles in the Ariège River catchment, and produce a chronofunction of related contrasts in terrace tread topsoil characteristics. Each profile consists of 9 to 11 gravel samples collected over depths of 4.6 to 15 m. Terrace T1 (+ 15 m above the current riverbed) was sampled at ~ 4, 22 and 53 km downstream from the Last Glacial Maximum terminal moraine system of the Ariège outlet glacier. The profiles of T2 (+ 30 m) and T3 (+ 50 m) complete the data set. Beryllium-10 age profiles date the age of terrace tread abandonment as a result of fluvial incision. Results show that the incision of T1 occurred over a protracted period during the Last Termination, beginning ca. 17.5 – 3.5 + 2.0 ka. Prior to this, aggradation occurred from MIS 4 to the global Last Glacial Maximum (LGM), i.e.,under maximum ice extent conditions, and lasted a few thousand years thereafter. The protracted influx of debris after the LGM was sustained by paraglacial storage release in the catchment and promoted by strong coupling between slope and channel processes. Fluvial incision of T1 occurred during the post-LGMcold-to-warm transition after a time (supported by paleobotanical evidence) when the vegetation cover was capable of ensuring catchment-wide slope stability. The wave of incision propagated downstream between 17.5 – 3.5 + 2.0 ka (proximal profile) and 13.0 – 0.5 + 3.5 ka (distal profiles). The exposure-age confidence intervals for T2 and T3 are much larger than for T1 (60–145 ka and 204–226 ka, respectively) but the data nonetheless allow the aggradation of T2 and T3 to be attributed to MIS 6 and MIS 8, respectively. The soil chronosequence permitted by the fill-terrace age sequence indicates that the Luvic Cambisols capping T1 formed after ~ 13–16 ka, i.e.,during the Holocene; (ii) the Haplic Luvisols capping T2 required at least ~ 130 ka, i.e.,two interglacials; and (iii) the deeply rubified, highly eluviated Luvisols capping T3 required at least ~ 250 ka, i.e.,at least three interglacials. [ABSTRACT FROM AUTHOR]

The chronology of the late Pleistocene glaciation in the Massif Central, France, is not well documented and there are divergent hypotheses regarding the timing of glacial events in this area. This study aims at reconstructing the chronology of late Pleistocene glacial fluctuations in the Aubrac Mountains. We present a new set of Be-10 and Al-26 exposure ages from twenty erratic boulders embedded in six glacial landforms. Glacial landforms were sampled to determine the timing of three glacial stades and the deglaciation of the Aubrac Mountains. These new data allowed us to constrain the timing of: (i) the Local Last Glacial Maximum, which is coeval with the early Marine Isotopic Stage 2 (MIS 2) (28–24 ka), and (ii) the Grandvals and Bouquincan stades, which are both coeval with the late MIS 2 (24–16 ka). Deglaciation occurred during Heinrich Stadial 1 (18–15.6 ka). This new direct glacial chronology is supported by regional paleoenvironmental proxies and it updates the chronostratigraphic framework available for the southwestern Massif Central. Western European atmospheric circulation changes (i.e., a southward shift in North Atlantic storm tracks and Mediterranean influences) during MIS 2 were identified as significant factors controlling glacier growth in the Aubrac Mountains as well as other glaciated mountains within the southwestern Massif Central, such as the Cantal, Margeride and Lozère mountains. • The Aubrac icefield fluctuations (Marine Isotopic Stage 2) were used as significant climatic proxies in the Massif Central. • Timing of three distinct glacial stades were inferred from cosmogenic exposure dating (n = 20). • The Local Last Glacial Maximum was coeval withthe early Marine Isotopic Stage 2 (28–24 ka). • Minor glacier advances were recorded during the late Marine Isotopic Stage 2 (24–16 ka). • The Heinrich Stadial 1 (18–15.6 ka), characterized by an arid climate, was coeval with the Aubrac Mountains deglaciation. [ABSTRACT FROM AUTHOR]

A new chronology of the last glaciation is established for the Krkonoše (Giant) Mountains, Central Europe, based on in-situ produced 10Be in moraine boulders. Exposure ages and Schmidt Hammer rebound values obtained for terminal moraines on the northern and southern flank of the mountains suggest that the oldest preserved moraines represent early phases of the Last Glacial Maximum (LGM). Large moraines at the outlet of the Snowy Cirques (Śnieżne Kotły) and in the middle part of the Úpa (Obří důl) trough were deposited around 21ka while a series of smaller moraines above the LGM deposits represent readvances that occurred no later than 18.1±0.6ka, 15.7±0.5ka, 13.5±0.5ka and 12.9±0.7ka. An exposure age of 13.8±0.4ka obtained for protalus ramparts at the foot of the Úpská jáma Cirque headwall indicates that glaciers advanced only in north- to east-facing cirques during the Lateglacial. The last glacier fluctuation was synchronous with the Younger Dryas cold event. The timing of local glacier advances during the last glacial episode correlates with the late Weichselian glacier phases in the Alps and in the Bavarian/Bohemian Forest. [ABSTRACT FROM AUTHOR]

Late Quaternary slip rates characterize the seismic potential of an active fault in terms of estimating the average expected recurrence period for rupturing episodes. Along the Baikal Rift faults the slip rate distributions are poorly understood. This study provides morphotectonic and paleoseismological analyses of the Kichera Fault that stretches within the North Baikal Rift over a length of 100 km. Exposure ages of key displaced terraces of the Neruchanda River from in-situ produced cosmogenic 10Be depth profiles show that the highest terrace T5 is older than 315 ka, intermediate terrace T3 was abandoned 100.0 ± 30 ka ago and the lowest terrace T1 is as old as 48.3 ± 19.9 ka. These exposure ages, coupled with terrace elevation from the actual Neruchanda River bed, allow us to estimate the incision rates for the corresponding time periods which are 0.1 (maximum), 0.16 ± 0.05 and 0.19 ± 0.08 mm yr−1, respectively. Using the cumulated amplitudes of the terrace displacement, we estimate the vertical slip rates along the Kichera Fault are 0.42 ± 0.13 and 0.19 ± 0.08 mm yr−1 over the last ~100 ka and ~48.3 ka, respectively. Paleoseismological studies including morphomertic analyses of the tectonic scarp and trenching across the fault allowed estimating the age (5.4 ka) and minimum magnitude (6.8) of the last Kichera Fault rupture. Using the estimates of short- and long-term slip rates, we propose mean recurrence intervals of 5.3 and 2.4 ka, respectively. The last interval is shorter than the time since the last earthquake, indicating that the future event could be of greater magnitude to maintain the long-term average slip rate. [Display omitted] • Terraces deformed by the Kichera Fault were dated using In-situ 10Be method. • Vertical slip rates along the Kichera Fault show high variability through time. • Age and magnitude of the last rupture along the Kichera Fault were estimated. • Kichera Fault is the major regional hazard source with a high seismic potential. • Kichera Fault may rupture in the nearest time during the seismic cluster. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the denudation rates in the Quadrilátero Ferrífero, Minas Gerais State (Brazil). The aim is to compare chemical weathering rates from measurements of solute fluxes in rivers and long-term mean erosion rates deduced from in situ-produced cosmogenic 10Be concentrations measured in fluvial sediments. Both water samples and sediments were collected in fifteen stations (checkpoints) located in four hydrographic basins with low anthropogenic perturbations. Depending of the type of substratum, three degrees of chemical denudation rates from water samples are observed: (i) high rates in marbles; (ii) medium rates in schists, phyllites, granites, gneisses and migmatites; (iii) low rates in quartzites and itabirites. Preliminary results of long-term erosion rates deduced from in situ-produced 10Be are comparable with those of chemical rates. [Copyright &y& Elsevier]

We perform a systematic and detailed study of the 14C and 14C‐10Be dating systems for meteorite terrestrial ages. Physical model calculations indicate that neither the 14C production rates nor the 14C/10Be production rate ratios are constant enough to be reasonably approximated by average values. By using simple averages, one introduces a significant size‐dependent bias into the database for meteorite terrestrial ages. By combining modeled 14C production rates and 14C/10Be production rate ratios with (22Ne/21Ne)cos ratios and assuming ~80% ablation losses, relatively easy to use correlations of 14C production rates and 14C/10Be production rate ratios as a function of (22Ne/21Ne)cos are established. The new correlations enable the determination of terrestrial ages that are more accurate than ages based solely on average values for 14C and/or 14C/10Be. We validate the model predictions by measuring 14C activity concentrations, 14C/10Be production rate ratios, 21Necos concentrations, and (22Ne/21Ne)cos ratios in four recently fallen meteorites: Mt. Tazerzait, Boumdeid (2011), Bensour, and SaU 606. The experimental data confirmed the model predictions, although the available data are insufficient to be conclusive. More data from freshly fallen meteorites are needed for validating the model predictions for different chondrite sizes and chondrite types. [ABSTRACT FROM AUTHOR]

Despite a wealth of recent studies dealing with the evolution of the drainage network in the uplifted Ardennes massif (E. Belgium), especially from the Middle Pleistocene onwards, the Ardennian landscape evolution and long-term incision rates in the Meuse catchment remain poorly documented over the whole Plio-Quaternary. Alluvium-filled multilevel cave systems represent a relevant setting to unravel the Late Cenozoic history of regional river incision. We present here a dataset of 26Al/10Be concentration data obtained from fifteen pebble samples washed into the Chawresse system, one of the largest multi-level cave systems of Belgium, which developed in Devonian limestones of the lower Ourthe Valley, the main Ardennian tributary of the Meuse. The sample collection spans an elevation difference higher than 120 m and their depleted 26Al/10Be ratios yield burial ages ranging from ~0.25 to 3.28 Ma. After critical assessment of our dataset for intra-karstic reworking issues, the most striking outcome of the obtained burial ages is the acceleration by a factor five of the incision rates (from ~30 to ~150 m/Ma) during the first half of the Middle Pleistocene. Integrating this incision peak and our pre-burial denudation rates, we then revisit the existing framework of Plio-Quaternary denudation and river incision in the Ardennian Meuse catchment. Whilst our 26Al/10Be concentration data shed new light on the temporal and spatial variability of the local river and hillslope system response to coupled tectonic and climatic forcings, it simultaneously highlights sampling issues and the need for further chronological data. • Ardennian multi-level cave system (Belgium) spanning a height difference >120 m • 26Al/10Be burial dating of fluvial sediments whose ages range from ~0.25 to 3.28 Ma • Critical assessment of our dataset because of probable intra-karstic reworking issues • Five-fold increase of incision rates (~30 to ~150 m/Ma) during the Middle Pleistocene • Spatio-temporal variability of regional river response during the Plio-Quaternary [ABSTRACT FROM AUTHOR]

Coarse debris accumulations cover large areas in high latitude and mountain environments, but their age and origin remain mostly unknown. Here we reassess the morphology of a prominent coarse debris accumulation in the Sudetes Mountain range in central Europe and constrain its timing with 10Be surface exposure data. Our observations indicate that the landform in the south-eastern slope of the Suť ridge appears consistent with the morphology of a block slope. The oldest minimum age of 150.1 ± 4.8 ka obtained for the tor at the upper limit of the block slope indicates the disintegration of the ridge and surface lowering under periglacial conditions prior to the last glacial-interglacial cycle. Four exposure ages retrieved for block samples range from 84.3 ± 3.8 to 26.8 ± 2.6 ka, providing evidence for block emplacement during the last cold peri od. The exposure ages extend existing chronological dataset for peri/glacial landforms in the Sudetes and constrain the timing of cold environments in the area prior the Last Glacial Maximum. The ages are also consistent with surface exposure data reported for block fields and block slopes in Western Europe and confirm the formation of similar landforms over the last glacial period in the Sudetes. [ABSTRACT FROM AUTHOR]

Relationships between spatially variable accommodation rate and the distribution of channel belt deposits are important issues in alluvial stratigraphy. This segment of sedimentology still records important progress using experimental models and field examples. This study focuses on the alluvial stratigraphy of the Volkovce Fm. which was deposited between ~9.0–6.0 Ma in the northern Pannonian Basin System, and it provides an excellent natural laboratory to study this topic. The spatial variability of channel belt distribution was determined in 809 borehole logs drilled to 200–300 m depths while the facies associations were defined on the outcrops. A significant variance in channel belt content was observed, since it reaches 10–40% of the stratigraphic column in the southwestern part of the study area and only 0–15% in the northeastern portion. Moreover, the transition between the areas of different channel belt distribution is oriented perpendicular to the paleo-drainage network axis. Geochronology was then established by applying the authigenic 10Be/9Be dating method to three borehole cores. The Bayesian age-depth models used herein proved a decrease in average accommodation rates from ~200 m/Myr to ~50 m/Myr towards the area with <15% of channel belts. The results indicate that the four times higher subsidence caused dominant deposition of channel belts in the area of maximum subsidence and avoided the basin-scale avulsion to relocate the channels in the area of lower accommodation rate. This was most likely caused by topographic confinement. The deposition of poorly-drained floodplain and swamp facies appeared in the area of lower accommodation rate, where absence of channels caused low sediment supply. The study highlights that authigenic 10Be/9Be dating Bayesian age-depth models can provide a strong geochronological framework for the late Cenozoic alluvial depositional record necessary for interpretation of the influence of allogenic factors on stratigraphic architecture. Unlabelled Image • Alluvial channel belt distribution variability studied in period ~9.0–6.0 Ma, dated by authigenic 10Be/9Be • Channel belts form 10–40% in the SW part of the area but only 0–15% in the NE part. • The four times higher subsidence attracted channel network to the area with maximum subsidence. • Channel deposition control sediment supply, linked to positive relief and well-drained floodplain • Poorly-drained floodplain related to negative relief occurred in low subsidence area. [ABSTRACT FROM AUTHOR]

• The Vosges Massif: a formerly half-glaciated massif. • 10Be- and 26Al-based catchment-wide denudation rates at the massif scale. • 40% of the studied catchments (9/22) are in cosmogenic disequilibrium. • Glacial deposits and former glacial cover correlates with 26Al/10Be ratios. • Sediments sampled in non-steady catchments might have survived several glacial cycles. Although catchment-wide denudation rates inferred from in situ cosmogenic nuclide concentrations measured in stream sediments has represented a ground-breaking progress in geomorphology over the last three decades, most of these studies rely on 10Be concentrations only. It seems that this current and routine one-nuclide approach to infer catchment-wide denudation rates has somehow overshadowed two key assumptions that are cosmogenic steady-state and short sediment transit time at the catchment scale. Although a paired-nuclide approach allow testing these assumptions, it is rarely performed on stream sediments and this can become highly problematic in slow-eroding, formerly glaciated contexts. In this study, we thus measure both 10Be and 26Al in stream sediments pertaining to twenty-one rivers draining an entire low mountain range: the Vosges Massif (NE France). The latter exhibits a sharp gradient between its southern and northern part in terms of lithology, morphometry and climate. Moreover, if its northern part remained void of glacial cover during Quaternary cold stages, its southern part was significantly and repeatedly glaciated. We aim to assess the factors that control the denudation of the Vosges Mountains and to quantitatively explore the impact of both repeated glacial cover and storage of glacially derived sediments on 26Al/10Be ratios, hence cosmogenic (un-)steadiness in modern river samples. Our results first show that elevation, slope, channel steepness and precipitation are primarily organised along a N-S increasing trend. 10Be- and 26Al-derived catchment-wide denudation rates accordingly range from 34 ± 1 to 66 ± 2, and 41 ± 3 to 73 ± 7 mm/ka, respectively, in thirteen investigated catchments that are in cosmogenic equilibrium. Lithological contrasts may control the pattern of denudation with a higher erodibility of the sandstone-dominated catchment to the north compared to the crystalline-dominated catchments to the south. Our results also show that catchments in strong cosmogenic disequilibrium (26Al/10Be ratios from 1.4 to 5.2) spatially cluster in the SW part of the Vosges Mountains that was the most intensively glaciated during Quaternary cold stages. If this precludes any conclusion about controlling factors at the whole massif scale, this study is the first to quantify the impact of past glaciations on cosmogenic (un-)steadiness measured in stream sediments. A statistically significant relationship between the degree of depletion of the 26Al/10Be ratios and the spatial pattern of glaciation is found: the larger the former glacial cover in each catchment, the lower the 26Al/10Be ratio. Equally important is the significant correlation reported between the degree of depletion of the 26Al/10Be ratios and the proportion of glacial and fluvio-glacial deposits within each catchment. These two relationships underline the link between cosmogenic unsteadiness in the stream cosmogenic signal and long-lasting and repetitive ice shielding, and complex sediment routing systems in glacial environments, respectively. We thus argue to systematically measure 26Al in complement to 10Be and to test the steady-state assumption when it comes to infer catchment-wide denudation rates from modern stream sediments, especially in slow eroding, formerly glaciated landscapes. [ABSTRACT FROM AUTHOR]

Cosmogenic radionuclide 10Be and 26Al targets (BeO and Al2O3) for AMS analysis are produced by a growing number of geochemical laboratories, employing different sample processing methods for the extraction of Be and Al from environmental materials. The reliability of this geochronological tool depends on data reproducibility independent from the preparation steps and the AMS measurements. Our results demonstrate that 10Be and 26Al concentrations of targets processed following different, commonly used protocols and measured at two AMS facilities lead to consistent results. However, insoluble fluoride precipitates, if formed during processing, can cause decreased 26Al results, while 10Be concentrations are unaffected. [ABSTRACT FROM AUTHOR]

Successions deposited under rifting and post-rift settings of an isolated epicontinental basin often exhibit contrasting characteristics. Facies linked to transgression during basin rifting are typically locally sourced fan deltas transporting coarse-grained sediment, whereas the post-rift setup generally involves a normal regression marked by more extensive catchments, sediment sourced from greater distances, and an overall decrease in average grain size compared to the transgressive facies. In this study, we present a specific scenario based on a sedimentological, stratigraphic, and authigenic 10Be/9Be analysis of the Nemčiňany Formation, an Upper Miocene fan deltaic succession in the eastern Danube Basin, Slovakia. Deposition of the Nemčiňany Fm. was initiated shortly after ~11.6 Ma by the fourth rifting phase of the Pannonian Basin System, triggering the transgression of Lake Pannon. The depositional system persisted until ~9.6 Ma, likely balancing the increased accommodation rate with sediment supply in the shallow lake area situated on a basement high. Subsequently, a relative decrease in the accommodation rate prompted the progradation of shelf-slope scale clinoforms, originating from the Nemčiňany depositional system, toward the center of the Komjatice depression at ~9.4 Ma, resulting in a normal regression of Lake Pannon. The persistence of the Nemčiňany fan delta system, unlike common stratigraphic patterns, was associated to the high sediment supply yielded by the paleo-Hron river, which entered the basin in the study area. These observations underscore the need for caution in predicting provenance shifts during changes in geodynamic stages of a basin. [ABSTRACT FROM AUTHOR]

• Pre-Acheulean industry dating at Dungo IV site (Baia Farta, Benguela, Angola). • Burial of the hominin occupation surface since at least 614 ka. • Apparent maximum uplift rate at the site of 170 m.Ma −1. Along the Angolan coast, the Early Paleolithic sites of Dungo IV and V (Baia Farta, Benguela) have delivered a rich pre-Acheulean lithic industry testifying the antiquity of the hominin settlement in western Africa despite the current absence of any hominin fossil in the area. In Dungo IV, the Paleolithic level is located on a conglomeratic paleo-beach (104 m a.s.l.) buried under an at least 3 m thick sandy layer. In Dungo V, two unearthed large whale fossils are associated with numerous lithic tools intimately mixed with the whale bones. This is the oldest evidence of stranded marine mammal scavenging by hominins in this part of Africa. The lack of volcanism and fossils makes chronological constrain difficult. Considering its configuration, the Dungo IV site may be relevant for a dating based on both the 10Be and 26Al cosmogenic nuclides. For this purpose, a depth profile all along the sandy layer overlying the archeological layer has been sampled. Statistical treatments performed on the 26Al/10Be ratios obtained for the depth profile demonstrate that they all belong to the same population. If we consider that the samples have always been at or close to their sampling depth, the regression modeling allows computing that the surface sedimentary layer has been emplaced at least 614 ka ago and less than 662 ka ago. On the other hand, if we consider that the surface deposit has been truncated, burial durations ranging from 585 ka to 786 ka and truncations lower than 4 m result from the modeling of the evolution of the 10Be and 26Al concentrations as a function of depth. The analyses of four pre-Acheulean artefacts lead to a minimum burial duration of 730 ka and a maximum burial duration of 2.11 Ma. The low pre-burial denudation rates modeled from the data acquired for the stone tools as well as for the overlying layer (1–16 m.Ma −1) imply large inherited 26Al and 10Be concentrations. The post-depositional maximum denudation rate of 71 m.Ma −1 associated with both the lithic artefacts and the surface sedimentary layer (considering that the samples have always been at or close to their sampling depth) as well as the deduced maximum uplift rate of ∼170 m.Ma −1 are in agreement with the known tectonic evolution and the climatic variability of this area. This study confirms the antiquity of the hominin presence in western Africa more than 2000 km away from the closest old hominin fossil sites. [ABSTRACT FROM AUTHOR]

Despite significant progress in understanding the stability of rock slopes, little is known about the time scales of the evolution of slow-moving rockslides. The Ledové sluje rockslide in the Thaya River canyon is a unique and infrequent slope failure developed in crystalline rocks of the Variscan orogen in Central Europe. Fresh topography with trenches, rock walls, slided blocks, scree slopes and crevice-type caves has attracted generations of geologists for more than a century, but questions of mechanism and age of the rockslide have remained unresolved. To address this question, we combined geomorphological research with detailed analysis of the geological structure, electrical resistivity profiling and terrestrial cosmogenic nuclide dating (TCN). Our data show that failure developed above the river undercut bank along a planar sliding surface predisposed by NW-oriented gently dipping metamorphic foliation intersected by steep fractures and faults. Although TCN dating does not allow determination of the entire life span of the rockslide, its scarp predisposed by NE- to ENE-striking fault was largely exposed in the Last Glacial during marine isotope stages (MIS) 3 and 2 between ~ 43 and 23 ka, suggesting slow gradual or multievent movement of the rockslide slope rather than a single catastrophic event. We conclude that, although very rare in Central Europe, rockslides in the crystalline rocks of the Palaeozoic orogens may leave a much longer topographic footprint than in the adjacent Alpine mountain belts. [ABSTRACT FROM AUTHOR]

Abstract We estimate recent (20 ka) incision and lateral migration rate on a spectacular ~N-S striking gorge cross-cutting N-dipping limestones in a fold-and-thrust belt of the external Southern French Alps. Upstream of the gorge, the river makes a right angle turn and follows the limestone surface parallel to the bedding direction (~EW). Eighteen samples were gathered along two vertical river polished profiles and three others on the denuded north-dipping surface layer, in order to determine river incision and lateral migration timing and rates. Surface age exposures of polished river cliff and bedding surface have been obtained from 36Cl cosmogenic nuclide dating and allow us to constrain the rate of vertical incision and of surface denudation of the Jurassic limestone layer. Fifteen 36Cl exposure ages have been obtained and range from ~21 ka to ~3 ka. Samples clearly define two age/height linear trends, which slopes correspond to incision rates of 1 and 0.3 mm/yr, respectively. The transition from low to high incision rate occurs at about ~12 ka, i.e. during the Younger Dryas glacial phase. Data also indicate that the vertical incision of the N-S branch of the gorge is coeval with the lateral (northward) river migration of its E-W branch associated with the denudation of the limestones surface. Extrapolating incision rates deduced from 36Cl exposure ages through time suggests that the incision of the Clue and denudation of the Jurassic limestones started about 500–600 ka ago. [ABSTRACT FROM AUTHOR]

Abstract The trans-boundary Slovak-Hungarian Domica–Baradla cave system (Slovak and Aggtelek karsts), >26 km in length, consists of evolution levels that have been formed in relation to the incision phases of the Jósva Valley. Existing opinions on the age of the well-known cave system have not been based on the dating of cave sediments deposited during older evolution phases. Previous U-series dating and the first paleomagnetic analyses of dripstones, flowstones and fine-grained allochthonous sediments identified only younger accumulative phases of the cave evolution in Late Pleistocene. Our cosmogenic nuclide dating (10Be and 26Al) of allochthonous fluvial gravels from the upper and lower levels of the Domica Cave (Slovakia) reveal much older evolution phases. Two burial ages at 3.47 ± 0.78 Ma and 2.94 ± 0.50 Ma show that the upper level of the cave system originated in, or before, the Middle Pliocene. Its younger accumulation phases (Early–Middle Pleistocene) are documented based on magnetostratigraphy and U-series dating of fine-grained sediments and flowstones. The Brunhes/Matuyama boundary (780 ka), Kamikatsura excursion (~900 ka), Santa Rosa excursion (~932 ka) and Jaramillo magnetozone (~1.001–1.069 Ma) were identified from the newly studied profile in the Suchá chodba Passage (the ages of flowstones in upper part of this profile are ~130 ka, 173 ka and 199 ka). In some places, several small older (paleokarst?) solutional phreatic cavities are cut by this cave level. The lower evolution level, located 12–18 m below the upper level, originated in the Early Pleistocene (the burial age of allochthonous fluvial gravels is 1.92 ± 0.25 Ma). Low pre-burial denudation rates (3.1–5.6 m/Ma) correspond with the slowdown or interruption of tectonic uplift of the area and the long-term stabilized erosion base level during the formation of these cave levels. Their origin was linked with the formation of large pediments, of which remnants are preserved on both sides of the Jósva Valley (Hungary). The pediments probably correlate to the 'foothill' (Middle Pliocene) and 'river-side' (Late Pliocene–Early Pleistocene) levels in the denudation chronology of the Western Carpathians. Highlights • Fluvially-modelled cave levels developed in relation to the formation of large pediments. • Combined use of absolute dating methods for the reconstruction of cave chronology. • The largest cave levels in the marginal part of the Western Carpathians formed in the Middle Pliocene and Early Pleistocene. • Paleo-denudation rates during the formation of cave levels are equivalent to low denudation rates of old cratons. • Refined denudation chronology of the Western Carpathians during the Middle Pliocene. [ABSTRACT FROM AUTHOR]

Deglaciation chronology of the Polish High Tatra Mountains has been reconstructed based on 10 Be exposure age dating. Fifty-seven rock samples were collected from boulders located on the terminal and lateral moraines that limit the horizontal extent of the LGM and the Lateglacial glaciers in the Biała Woda and Sucha Woda catchments. The uncertainty-weighted mean age of 21.5 ± 2.5 ka obtained for the maximum terminal moraine in the Sucha Woda Valley indicates that the oldest preserved moraines were formed during the global LGM. The age population ranges between 15.1 ± 1.0 and 28.3 ± 2.0 ka, and suggests that glaciers reached their maximum position (LGM I) as early as 28–25 ka and the final stabilization of the form occurred much later possibly after melting of buried dead ice. The younger glacial oscillation (LGM II) occurred no later than 20.5 ka and is represented by well-preserved termino-lateral moraine systems in the Pańszczyca Valley. The first Lateglacial stage (LG1) in the study area is documented in the Rybi Potok Valley at the RP1 moraine (1300 m a.s.l.), which was stable at around 16.6 ± 0.3 ka. The younger LG2 stage has no defined absolute age, however, it is constrained between 16.5 and 15.5 ka by the timing of the LG3 stage. This cold event is represented by well-formed moraines in the Roztoka/Pięć Stawów Polskich, Rybi Potok and Pańszczyca valleys of which exposure age indicates their deposition between 15.0 ± 0.5 and 15.6 ± 0.1 ka. The LG1, LG2 and LG3 stages likely occurred during the Oldest Dryas cold stage (Greenland Stadial 2.1a) related to the North Atlantic cooling Heinrich Event 1. The youngest glacial oscillation is evidenced by moraines in the Pusta and Pańszczyca valleys. These moraines are composed of very large granitic blocks of which exposure ages often exhibit isotope inheritance. This is reflected by the youngest P3 moraine in the Pańszczyca Valley with a mean age of deposition close to the LGM. The R4 moraine system in the Pusta Valley, however, indicates two oscillations phases that occurred at around 13 ka and correlates well with the timing of RP5 moraine formation in the Za Mnichem Valley. The LG4 stage is related to the climate cooling during the Younger Dryas (Greenland Stadial 1). LGM ELAs reconstructed for the Biała Woda and Sucha Woda/Pańszczyca glaciers were located at 1460–1480 m a.s.l. During the Oldest Dryas stages, the ELA in the High Tatras rose from 1600 to 1650 m a.s.l. in the Rybi Potok Valley and from 1700 to 1800 m a.s.l. in the Roztoka/Pięć Stawów Polskich Valley. The Younger Dryas ELA, depending on glacier's exposition, was located between 1950 and 2000 m a.s.l. Climate modelling results show that the LGM glaciers (maximum advance) could have advanced in the High Tatras when the mean annual temperature was lower than today by 11–12 °C and precipitation was reduced by 40–60%. During the Lateglacial stages the temperature decrease in the study area changed from 10 °C during the Oldest Dryas to 6 °C during the Younger Dryas and precipitation lowering decreased from −50% to −30% or even −10%, respectively compare to modern conditions. [ABSTRACT FROM AUTHOR]

10 Be exposure ages from moraines and bedrock sites in the Roháčská Valley provide chronology of the last glaciation in the largest valley of the Western Tatra Mts., the Western Carpathians. The minimum apparent exposure age of 19.4 ± 2.1 ka obtained for the oldest sampled boulder and the mean age of 18.0 ± 0.8 ka calculated for the terminal moraine indicate that the oldest preserved moraine was probably deposited at the time of the global Last Glacial Maximum (LGM). The age of this moraine coincides with the termination of the maximum glacier expansion in other central European ranges, including the adjacent High Tatra Mts. and the Alps. The equilibrium line altitude (ELA) of the LGM glacier in the Roháčská Valley, estimated at 1400–1410 m a.s.l., was 50–80 m lower than in the eastern part of the range, indicating a positive ELA gradient from west to east among the north-facing glaciers in the Tatra Mts. Lateglacial glacier expansion occurred no later than 13.4 ± 0.5 ka and 11.9 ± 0.5 ka, as indicated by the mean exposure ages calculated for re-advance moraines. This timing is consistent with the exposure age chronology of the last Lateglacial re-advance in the High Tatra Mts., Alps and lower mountain ranges in central Europe. The ELA in the Roháčská Valley estimated at 1690–1770 m a.s.l. in this period was located 130–300 m lower than in the north-facing valleys in the High Tatra Mts. 10 Be exposure ages obtained for a rock glacier constrains the timing of this landform stabilization in the Salatínska Valley and provides the first chronological evidence for the Lateglacial activity of rock glaciers in the Carpathians. [ABSTRACT FROM AUTHOR]

Assessment of vertical movements of tectonically bounded blocks is crucial for determination of geohazards in densely inhabited zones, such as the border zone of western Slovakia and eastern Austria. The morphostructure of the Malé Karpaty Mts. divides the Vienna and Danube basins in the Western Carpathian - Eastern Alpine junction, and its neotectonic activity is of high importance. This study was focused on 26Al/10Be burial dating of fluvial sediment in the Stará Garda Cave, located in the central part of the mountains. The structural research revealed predisposition of forming of horizontal passages in low angle to subhorizontal bedrock stratification together with low-grade metamorphic foliation. Fluvial origin of the passages was inferred from mezoscale erosional features on the bedrock as well as from facies character of the well preserved sedimentary profile. Cave sediment was according to petrographic analysis derived from a watershed comparable to recent one of the Stupavský Potok Stream. Three analysed dating samples provided low values of isotopic concentrations, allowing us only to calculate the minimum burial age of the deposit of 1.72 Ma. Assuming the low position of the cave above recent surface streams, resulting maximum incision rate of 26 m/Ma indicates very low uplift of the mountains horst during the quaternary. The slow incision of the river network is in good agreement with a widespread preservation of the planation surface called "Mid-mountain level". In contrast are relatively high values of palaeodenudation rates inferred from isotopic concentrations. Generally, our results indicate that the Malé Karpaty Mts. horst underwent relatively intense but short uplift in the Early Pleistocene, followed by very moderate uplift up to the recent. [ABSTRACT FROM AUTHOR]

The authors offers information on a study on geomorphic record along the General Carrera, Chile and Buenos Aires, Argentina, Glacial Lake, in response to a comment by Martinod et al. Topics discussed include cold events as recorded by the outer moraine and the inner moraine, glacial rebound and morphological description of the Rio Bayo/Rio Tranquilo valley.

Through the investigation of terrestrial ages of meteorites from Oman, we aim to better understand the time scales of meteorite accumulation and erosion in Oman and the meteorite flux in the past. Here, we present 14C and 14C‐10Be terrestrial ages of seven ordinary chondrite strewn fields and two unpaired single meteorites from the Sultanate of Oman. After critical evaluation of multiple data for each strewn field, we propose "best estimate terrestrial ages," typically based on 14C/10Be. For objects for which complex irradiation histories are known or suspected, terrestrial ages were calculated solely using 14C. The best estimate strewn field ages range from 8.1 ± 3.0 ka (SaU 001) to 35.2 ± 5.1 ka (Dho 005). Including two previously dated strewn fields, the mean and median age of nine Oman strewn fields is 15.9 ± 12.3 and 13.6 ka, respectively. The new data show a general good agreement with data previously obtained in a different laboratory, and we observe a similar general correlation between strewn field ages and mean weathering grade as in previous work based on individual meteorites. Weathering degree W4 is reached for dated samples after 20–35 ka. While the age statistics of strewn fields does not show the previously observed lack of young events, the low abundance of young (0–5 ka) individual meteorites as compared with older (~20 ka) meteorites is confirmed by our data and remains unexplained. [ABSTRACT FROM AUTHOR]

The migration of Homo erectus in Southeast Asia during Early Pleistocene is cardinal to our comprehension of the evolution of the genus Homo. However, the limited consideration of the rapidly changing physical environment, together with controversial datings of hominin bearing sites, make it challenging to secure the robust timeline needed to unveil the behavior of early humans. Here, we reappraise the first appearance datum of Javanese H. erectus by adding the most reliable age constraints based on cosmogenic nuclides 10 Be and 26 Al produced in situ to a compilation of earlier estimates. We find that H. erectus reached Java and dwelled at Sangiran, Java, ca. 1.8 Ma. Using this age as a baseline, we develop a probabilistic approach to reconstruct their dispersal routes, coupling ecological movement simulations to landscape evolution models forced by reconstructed geodynamic and climatic histories. We demonstrate that the hospitable terra firma conditions of Sundaland facilitated the prior dispersal of hominins to the edge of Java, where they conversely could not settle until the Javanese archipelago emerged from the sea and connected to Sundaland. The dispersal of H. erectus across Sundaland occurred over at least tens to hundreds kyr, a time scale over which changes in their physical environment, whether climatic or physiographic, may have become primary forcings on their behavior. Our comprehensive reconstruction method to unravel the peopling timeline of SE Asia provides a novel framework to evaluate the evolution of early humans. [ABSTRACT FROM AUTHOR]

Deglaciation chronology of the Bystra catchment (Western Tatra Mountains) has been reconstructed based on 10 Be exposure age dating. Fourteen rock samples were collected from boulders located on three moraines that limit the horizontal extent of the LGM maximum advance and the Lateglacial recessional stage. The oldest preserved, maximum moraine was dated at 15.5 ± 0.8 ka, an age that could be explained more likely by post-depositional erosion of the moraine. Such scenario is supported by geomorphologic and palaeoclimatological evidence. The younger cold stage is represented by well-preserved termino-lateral moraine systems in the Kondratowa and Sucha Kasprowa valleys. The distribution of the moraine ridges in both valleys suggest a complex history of deglaciation of the area. The first Late-glacial re-advance (LG1) was followed by a cold oscillation (LG2), that occurred at around 14.0 ± 0.7–13.7 ± 1.2 ka. Glaciers during both stages had nearly the same horizontal extent, however, their thickness and geometry changed significantly, mainly due to local climatic conditions triggered by topography, controlling the exposition to solar radiation. The LG1 stage occurred probably during the pre-Bølling cold stage (Greenland Stadial 2.1a), however, the LG2 stage can be correlated with the cooling at around 14 ka during the Greenland Interstadial 1 (GI-1d – Older Dryas). This is the first chronological evidence of the Older Dryas in the Tatra Mountains. The ELA of the maximum Bystra glacier was located at 1480 m a.s.l. in accordance with the ELA in the High Tatra Mountains during the LGM. During the LG1 and LG2 stages, the ELA in the catchment rose up to 1520–1530 m a.s.l. and was located approximately 100–150 m lower than in the eastern part of the massif. Climate modelling results show that the Bystra glacier (maximum advance) could have advanced in the catchment when mean annual temperature was lower than today by 11–12 °C and precipitation was reduced by 40–60%. This is in accordance with LGM conditions previously reported for the High Tatras. During the LG1 and LG2 stages the temperature decrease in the study area reached 10 °C and precipitation was lower by ∼30% compare to modern conditions. This resulted in slightly higher accumulation (20–30%) in the Western Tatra Mountains compare to the High Tatra Mountains. [ABSTRACT FROM AUTHOR]

We present geomorphic, stratigraphic, and chronological data acquired along the General Carrera-Buenos Aires (GCBA) glacial lake located along a major morphological incision across the Andes. Complementing relevant available data, relative chronology of morphoclimatic records together with 18 10Be cosmic ray exposure ages allow constraining the timing of the Patagonian ice sheet fluctuations since the last glacial maximum. It improves the knowledge of Patagonia climate evolution in the 46°-48°S area and allows documenting the uplift rates (glacial rebound) for the past ~7-9 ka. The first major ice lobe retreat occurred after 17.3 ± 0.6 ka and has likely continued during the Antarctic cold reversal from ~12.9 to 14.5 ka. Between ~12.9 and ~10.9 ± 1.3 ka, the General Carrera Lake evolved as an endorheic basin. Terraces T4-T1 (top to bottom) have recorded abrupt lake regressions likely controlled by rainfall deficit. They have accumulated in the time interval ~17.3-12.3 ka (maximum limits). Two glacial re-advances at ~10.9 ± 1.3 and ~7.9 ± 1.1 ka marked a major climate change that led the lake to be ice dammed again. A major transgression occurred that subsequently flooded the previously accumulated terraces. Since then, a pervasive regression has steered the GCBA Lake to the situation at present. The highest shoreline of the transgression is used as a passive marker in order to quantify the magnitude and character of the regional deformation. At long 72°30'W, the GCBA Lake area uplifted (glacial rebound) at a rate between 15 and 33.5 mm yr-1 during the past ~7.9 ± 1.1 ka. We infer that the high uplift rate mainly originates from the North Patagonian icefield ice loss. [ABSTRACT FROM AUTHOR]

10 Be exposure age chronology of the last glaciation was established in a key area at the southern slopes of the High Tatra Mts., Western Carpathians. In-situ produced 10 Be in moraine boulders, glacially transformed bedrock surfaces and rockfall accumulations constrains the timing of the Last Glacial Maximum (LGM) glacier expansion and provides chronological evidence for the post-LGM decay of one of the largest paleoglaciers in the range. The uncertainty-weighted mean age of 22.0 ± 0.8 ka obtained for the terminal moraine in the forefield of the Velká Studená dolina Valley indicates that the oldest moraine was deposited close to the global LGM. This finding confirms that well-preserved moraines in the range were formed during the last glacial cycle and that glaciation on the southern flank of the range was more extensive than earlier in the last glacial cycle. The maximum glacier extent correlates with late Würmian/Weichselian glacier phases in the Alps, the Bavarian/Bohemian Forest and the Krkonoše Mts., but probably postdates the period of maximum glaciation in the Southern Carpathians. Re-advance moraines at the mouth of the Velká Studená dolina Valley and in the middle part of the Malá Studená dolina Valley were deposited no later than around 20.5 ka and 15.5 ka, respectively. The timing of these advances is broadly synchronous within the High Tatra Mts. as well as with glacier advances in the Alps, Bavarian/Bohemian Forest and Krkonoše Mts. 10 Be exposure ages obtained from glacially transformed bedrock surfaces range between 20.5 ± 1.7 ka and 10.7 ± 0.3 ka constraining the onset and the final phase of the deglaciation. Surface exposure dating of four rockfall accumulations produced uncertainty-weighted mean ages of 20.2 ± 1.2 ka, 17.0 ± 0.7 ka, 16.5 ± 0.4 ka and 15.6 ± 0.7 ka. These ages indicate that activation of rock-slope failures occurred under paraglacial conditions within a few centuries up to 1400 years after the formation of re-advance moraines. [ABSTRACT FROM AUTHOR]

The 10 Be method was used to investigate the effect of mining activities on the natural denudation rates in alluvial sediments from catchments of the Southern Espinhaço Range (SER) in Minas Gerais State (Brazil). In this region, which is predominantly composed of quartzites, the 10 Be concentrations were measured in alluvial sediments from catchments in a preserved natural area of the Serra do Cipó National Park and on the Diamantina Plateau, which was subjected to diamond extraction from beginnings of XVIII century until the end of the XX. Two types of drainage were identified in the Diamantina Plateau area: (i) reworked drainage (alluvial sediments reworked by panning) and (ii) overloaded drainage (alluvial sediments originating from panning processes on saprolites located upstream). The mean denudation value for the natural drainages (∼4.4 m.My-1) is similar to that of the reworked drainages (∼4.3 m.My-1) However, the denudation rates obtained for eleven samples from three sites in overloaded basins range from ∼6.4 m My-1 to ∼22.8 m My-1 and are thus higher than those determined for the reworked and natural basins. These results show that despite the alluvium deposits have been intensely reworked by panning, the values of denudation rates were not changed, they are similar to denudation rates from the natural drainages. However, the natural rates are lower than those affected by panning processes on saprolites. [ABSTRACT FROM AUTHOR]

We analyze major landforms of the Lut Desert in Iran to provide a comprehensive source‐to‐sink picture of aeolian systems on time scales from decades to millions of years. We map the modern sandflows, along which we evaluate the volume and chronology associated with the excavation of mega‐yardangs upwind and the formation of giant dunes downwind. Sediment discharges deduced from long‐term erosion and deposition are of the same order of magnitude (105–106 m3 yr−1) as short‐term and medium‐term sand discharges derived from wind data and dune morphodynamics. At the scale of the internal aeolian sediment‐routing system of the Lut, we establish an overall sediment budget constrained by the joint development of the erosional and depositional landforms. Our findings thus quantify the geomorphic controls of aeolian processes on arid landscapes at multiple length and time scales, while providing information on mass exchanges between continents and atmosphere. Plain Language Summary: Wind‐blown sand and dust emissions shape singular landscapes in arid environments and globally impact climate, life, and human activities. Nevertheless, the contributions of aeolian processes to the evolution of continental surfaces and to their mass exchanges with oceans and the atmosphere are still subject to considerable uncertainties. Compared to sediment transport in rivers, this is because wind transport is not associated with a well‐identified channel network that directly links sand and dust production (source) to accumulation (sink) areas. The Lut Desert in Iran is nested in a closed topographic depression which provides an appropriate context to investigate the work of the wind. Spectacular landforms called mega‐yardangs and giant dunes are used together with modern wind data to map and quantify sandflows at different time scales. These sandflows are consistent with each other from decades to millions of years and allow to estimate the amount of sediments transported across the Lut Desert or emitted into the atmosphere. These estimates are not only important for the management of terrestrial drylands, but they can also provide information about the past evolution of planetary bodies dominated by aeolian processes such as Mars or Titan. Key Points: The wind regimes within the Lut Desert create an internal aeolian sediment‐routing systemThe joint development of erosional and depositional landforms are consistent with modern sandflowsSource‐to‐sink aeolian fluxes are of the same order of magnitude from decades to millions of years [ABSTRACT FROM AUTHOR]

The timing of mountain glacier fluctuations is poorly constrained in some parts of Greenland during the Late Holocene. We present 31 10Be cosmic‐ray exposure ages (CRE) of boulders collected from three mountain glacier moraines located in the Tasilap valley, in southeastern Greenland, and 10 10Be CRE ages from one mountain glacier in the Isortup valley, in southern Greenland. For the first time in these areas, mountain glacier fluctuations are documented from moraine CRE for the Late Holocene period. Several glacier advances during the Late Holocene are revealed with exposure ages ranging from 3.90±0.26 to 0.4±0.04 ka. Moraines of three of the four glaciers investigated, dated to 3.75±0.13 ka (n = 3), 3.3±0.19 ka (n = 2) and 2.87±0.13 ka (n = 3), show a common timing of the largest glacier expansion during the Late Holocene. Evidence of at least one individual moraine deposited at ~1.2 ka was found on all glaciers. Finally, the most recent period of glacial advance during the Late Holocene is documented by one glacier in each valley at ~0.66–0.70 ka. The maximum glacier extent at ~3 ka differs from the Late Holocene glacier maximum extent usually reported during the Little Ice Age in east Greenland based on moraine dating and lake sediments. We suggest that the combination of a stronger East Greenland Current and a weaker Irminger Current, potentially associated with increased sea‐ice concentration, superimposed on the long‐term decrease in summer insolation during the Late Holocene could be responsible for this large glacial advance at ~3 ka in southern and southeastern Greenland. [ABSTRACT FROM AUTHOR]

Abstract: Although it is generally assumed that the internal structure of a slope (e.g. lithology and rock mass properties, inherited faults and heterogeneities, etc.) is preponderant for the progressive development of large-scale landslides, the ability to identify triggering factors responsible for final slope failures such as glacial debuttressing, seismic activities or climatic changes, especially when considering landslide cluster at an orogen-scale, is still debated. Highlighting in this study the spatial and temporal concordant clustering of deep-seated slope failures in the external Southwestern Alps, we discuss and review the possible causes for such wide-spread slope instabilities at both local and larger (Alpine) scale. High resolution field mapping coupled with electrical resistivity tomography first allows establishing an inventory of large landslides in the Southwestern Alps, determining their structural model, precising their depth limit (100–200 m) as well as the involved rock volumes (>107 m3). We show that they developed in the same geostructural context of thick mudstone layers overlain by faulted limestone and followed a block-spread model of deformation that could evolve in rock-collapse events. Cosmic ray exposure dating (CRE), using both 36Cl and 10Be in coexisting limestone and chert, respectively, has been carried out from the main scarps of six Deep Seated Landslides (DSL) and leads to landslide-failure CRE ages ranging from 3.7 to 4.7 ka. They highlighted: (i) mainly single and fast ruptures and (ii) a possible concomitant initiation with a main peak of activity between 3.3 and 5.1 ka, centered at ca 4.2 ka. Because this region was not affected by historical glaciations events, landslide triggering by glacial unloading can be excluded. The presented data combined with field observations preferentially suggest that these failures were climatically driven and were most likely controlled by high pressure changes in the karstic medium. In effect, the chronicle of failure-ages is concomitant to a well-known climatic pulse, the “4.2 ka” climate event characterized by intense hydrological perturbations associated to the heaviest rainfall period of the entire Holocene. Despite requiring further investigations and discussions, the dating of numerous events across the entire Alps during the middle Holocene period suggests a potential synchronous triggering of several large-scale gravitational-failures induced by the mid-Holocene climatic transition. [Copyright &y& Elsevier]

It is still disputed whether very old archaeological and palaeontological remains found in the Belle- Roche palaeocave (eastern Belgium) pertain to the Early (∼1 Ma) or Middle (∼0.5 Ma) Pleistocene. Here, in situ-produced cosmogenic 10 Be concentrations from a depth profile in nearby sediments of the Belle- Roche terrace ( Amblève Main Terrace level) are used as an indirect solution of this chronological issue. The distribution of 10 Be concentrations in the upper 3 m of this profile displays the theoretically expected exponential decrease with depth. Assuming a single exposure episode, we obtain a best fit age of 222.5±31 ka for the time of terrace abandonment. However, below 3 m, the 10 Be concentrations show a marked progressive increase with depth. This distinctive cosmogenic signal is interpreted as the result of slow aggradation of the fluvial deposits over a lengthy interval. Modelling of the whole profile thus suggests that the onset of the terrace formation occurred at around 550 ka, with a sediment accumulation rate of ∼20 mm ka−1. Based on two slightly different reconstructions of the geomorphic evolution of the area and a discussion of the temporal link between the cave and Main Terrace levels, we conclude that the fossil-bearing layers in the palaeokarst pertain most probably to MIS 14-13, or possibly MIS 12-11. This age estimate for the large mammal association identified in the Belle- Roche palaeokarst and the attribution to MIS 14-13 of a similar fauna found in the lowermost fossiliferous layers of the Caune de l' Arago ( Tautavel) are in mutual support. Our results therefore confirm the status of the Belle- Roche site as a reference site for the Cromerian mammal association in NW Europe. [ABSTRACT FROM AUTHOR]

We measured noble gas concentrations and isotopic ratios (He, Ne, and Ar isotopes) in six recent ordinary chondrite falls: Mangui (L6), Viñales (L6), Ozerki (L6), Tamdakht (H5), Kheneg Ljouâd (LL5/6), and Katol (L6). Among them, the three L6 chondrites Mangui, Viñales, and Ozerki fell in only a few months' interval; their apparent similar petrographic and mineralogic characteristics might indicate source crater pairing. To test this hypothesis, we have investigated those meteorites for their cosmic ray exposure (CRE) histories, using the cosmogenic noble gases 3He, 21Ne, and 38Ar. We systematically (re)calculated the CRE ages as well as the gas retention ages of these meteorites. The CRE age of the Mangui is, based on noble gases, <1 Ma, which is unusually short for an L chondrite. Indeed, the range of exposure ages for L chondrites is generally distributed between ˜1 and ˜60 Ma, with major peaks occurring around ˜5, ˜30, and ˜40 Ma. In addition, the cosmogenic 3Hecos data of two Mangui duplicates are consistent with a remarkably high loss of helium by diffusion due to heating by solar radiation. Such a short parent body‐Earth transfer time (<1 Ma) can be explained by a delivery from an Earth‐crossing object. Regarding the other L6 chondrites, Viñales has a nominal CRE age of ˜9.4 Ma, whereas the Ozerki meteorite has a nominal CRE age of ˜1.2 Ma, which is consistent with Korochantseva et al. (2019). Based on their CRE ages as well as on their gas retention ages, it appears that none of these three recent L6 chondrite falls are source crater paired, and therefore, all three originate from different meteoroids. The nominal exposure ages of Tamdakht, Kheneg Ljouâd, and Katol are ˜3.2, ˜11, and ˜30 Ma, respectively, and are consistent with identified age peaks on the exposure age histogram of H, LL, and L chondrites, respectively. The nominal CRE age of Tamdakht is consistent with previous observations for H chondrites and implies that they are dominated by small impact events occurring in several parent bodies. [ABSTRACT FROM AUTHOR]

To investigate denudation rates in the southern part of the Espinhaço Range (central-eastern Brazil) and to understand how this important resistant and residual relief has evolved in the past 1.38My, cosmogenic 10Be concentrations produced in situ were measured in alluvial sediments from the three main regional basins, whose substratum is composed primarily of quartzites. The long-term denudation rates (up to 1.38My) estimated from these measurements were compared with those that affect the western (São Francisco River) and eastern (Doce and Jequitinhonha Rivers) basins, which face the West San Francisco craton and the Atlantic, respectively. Denudation rates were measured in 27 samples collected in catchments of different sizes (6–970km2) and were compared with geomorphic parameters. The mean denudation rates determined in the northern part are low and similar to those determined in the southern part, despite slightly different geomorphic parameter values (catchment relief and mean slope). For the southern catchments, the values are 4.91±1.01mMy−1 and 3.65±1.26mMy−1 for the Doce and São Francisco River basins, respectively; for the northern catchments, they are 4.40±1.06mMy−1 and 3.96±0.91mMy−1 for the Jequitinhonha and São Francisco River basins, respectively. These low values of denudation rates suggest no direct correlation if plotted against geomorphic parameters such as the catchment area, maximum elevation, catchment relief, average relief and mean slope gradients. These values show that the regional landscape evolves slowly and is strongly controlled by resistant lithology, with similar erosional rates in the three studied basins. [ABSTRACT FROM AUTHOR]

Abstract: A glacial chronology based on in situ-produced 10Be surface exposure dating of moraines in the Bohemian Forest (Central Europe) was established. Eleven exposure ages obtained for moraine boulders in the Prášilské Lake and Laka Lake valleys (Czech Republic) were complemented by 10Be ages from Kleiner Arbersee (Germany) recalculated according to recently calibrated production rates in the Northern Hemisphere. The glacial phases in the Bohemian Forest occurred during the Last Glacial Maximum around 24.1 ± 2.5, 23.6 ± 2.4, 21.8 ± 2.0 and 19.5 ± 2.1 ka. Following phases of local glaciation occurred during the Northern Hemisphere deglaciation period around 16 ka and 14 ka. The last indicated phase may correlate with Older Dryas. The glacial chronology of the Bohemian Forest is in agreement with local glaciation chronologies in the Giant Mts. (Krkonoše Mts.) and the Eastern Alps. [Copyright &y& Elsevier]

Abstract: Dartmoor, in SW England, is a classic periglaciated granite upland adorned with a population of over 150 tors. The origin of the tors has been controversial, but their emergence by differentiation after stripping of regolith during Pleistocene cold phases is accepted. However, their actual age has been unknown, with possible scenarios ranging from preservation since the early Middle Pleistocene to relatively short-lived landforms in a maritime climate with high denudation rates. The latter is now supported by 32 cosmogenic surface exposure dates from 28 tors across the whole upland. The distribution of apparent 10Be ages peaks strongly in the Middle Devensian (36–50 ka), which with corrections for weathering and limited ice shielding could be interpreted as Early Devensian. These ages are much younger than those found for three glacially unmodified Cairngorms tors, and somewhat younger even than glacially modified Cairngorms tors. The dates show little spatial variation. Although an ice cap has now been modelled in the heart of northern Dartmoor, tors here are of median age, suggesting that ice cover sufficient to shield tors from incoming radiation was of short duration. The few younger tor ages support the idea of continuing landform instability across the landscape, with weathering flakes redeveloping soon after inferred loss of top pillows by gelifraction or gravitational toppling. The few older tor ages have no systematic explanation, and may indicate inheritance from an earlier cycle of bedrock near-exposure. Since most tors are modest in height (typically 2–5 m), volumetrically insignificant, and often in advanced stages of disintegration, the general impression is that they are evanescent features, which emerge and quickly disappear during every Pleistocene climatic downturn. Tor populations may thus flicker across the landscape rather randomly over the Quaternary. The remarkably consistent age of the present tor population could be associated with a stripping event at the start of the Devensian, but fuller analysis must await closer controls on tor denudation rates in different climatic phases, and on ice cover extent and duration. These results only date extant tor surfaces, not the landscape, but as the best available erosion pins they have evident value in exploring theories of the evolution of Dartmoor during the Quaternary. [Copyright &y& Elsevier]

Abstract: New Terrestrial Cosmogenic Nuclides (TCN) 10Be ages obtained on glacially polished rocks from the SW Alps (Tinée Valley, France) allow a comparison with ages obtained using similar methods for dating the deglaciation steps after the Last Glacial Maximum on the northern and southern sides of the Alps. The data presented in this study highlight three stages of glacial retreat on the southern flank of the Alps at remarkably similar ages that are 14.9 ± 0.8 10Be ka for the end of Oldest Dryas cold period, 10.9 ± 1.1 10Be ka for the end of Younger Dryas cold period and 8.4 ± 0.9 10Be ka for a late ice retreat stage. Previously published data from the Northern Alps lead also to an age of 15.7 ± 1.0 ka for the Oldest Dryas deglaciation, followed by the Younger Dryas at 11.3 ± 1.0 ka, and a late discrete ice retreat event at 9.7 ± 1.2 ka. The last glacial retreats occur thus simultaneously across the Alps and the deglaciation process was most likely unrelated to variations in latitude or to mountain flank exposition throughout the Alps. This may be ascribed to a relatively rapid climate change. Subsequent mountain slope evolution following the rapid glacier unloading is reflected by landslides and fault reactivation directly following the deglacial period. This temporal coincidence is ascribed to a cause-to-consequence effect of glacial unloading and water infiltration into tectonic and landslide triggering. [Copyright &y& Elsevier]

A new 10Be data set from a small glacial catchment in the Pyrenees confirms almost full glacier extent during Marine Isotope Stage (MIS) 2, extends the oldest cosmogenic exposure ages of moraines in this mountain range to MIS 5, and constrains paleoclimate reconstructions in the Mediterranean region. It also illustrates the advantageous conditions for the long-term preservation of terminal moraines provided by small, low-gradient glacier catchments that did not merge with compound ice masses even during glacial maxima. These small, gently sloping, and isolated glacier catchments are proposed as priority targets for terrestrial cosmogenic nuclide dating of peak Pleistocene glacier advances, providing scope for greater accuracy in interregional paleoclimatic correlations. [ABSTRACT FROM AUTHOR]

Abstract: The concentrations of atmospheric cosmogenic 10Be normalized to the solubilized fraction of its stable isotope 9Be have been measured in the authigenic phase leached from silicated continental sediments deposited since the upper Miocene in the northern Chad Basin. This method is validated by the systematic congruence with the biochronological estimations based on the fossil mammal evolutive degree of faunal assemblages. The fifty-five authigenic 10Be/9Be ages obtained along 12 logs distributed along two West–East cross sections that encompass best representative Mio-Pliocene outcrops including paleontological sites show a systematic stratigraphic decrease when considering all studied sedimentary facies extending from the Pleistocene up to 8Ma and allow performing geologic correlations otherwise impossible in the studied area. The resulting global sequence evidences and temporally specifies the succession of the main paleoenvironments that have developed in this region since the Miocene. Under the special conditions encountered in the northern Chad Basin, this study demonstrates that the authigenic 10Be/9Be ratio may be used as a dating tool of continental sedimentary deposits from 1 to 8Ma. The half-life of 10Be theoretically allowing dating up to 14Ma, it may have fundamental implications on important field research such as paleoclimatology and, through the dating of fossiliferous deposits in paleontology and paleoanthropology. [ABSTRACT FROM AUTHOR]

Abstract: Sackungs are the largest gravitational deformation observed in mountains. They are characterized by the long-term slowness of the movements, but their mechanism is still not well understood. Nowadays cosmic ray exposure (CRE) dating methods allow dating the morphologic structures involved in sackung and can contribute at the understanding of their origin. In the Alps, the 5.3 km long Arcs sackung initiated during the activity of rock glaciers. Three samples from these faulted rock glaciers provide their first CRE ages and show that at 2000 m elevation these block accumulations moved during the Younger Dryas and stopped in early Holocene. Six 10Be ages of fault scarps show that the Arcs sackung lasted only a few thousand years and stopped at about 8462±432 10Be yr. They also reveal that deformation migrated upslope in agreement with a mechanism of flexural toppling of vertical layers. This unique and long gravitational event, characterized by migration of the deformation, does not support earthquake shaking as triggering mechanism for individual faults. It shows that, in the upper Isère valley, slope deformation was delayed of several thousand years after glacial debuttressing, and is not anymore active despite its fresh morphology. [Copyright &y& Elsevier]

Abstract: We present a chronology of ice recession in the eastern Pyrenees based on in situ-produced 10Be data obtained from the Têt paleoglacier complex. The sampling strategy is based on the relative chronology provided by a detailed geomorphological map of glacial landforms. Results indicate that the last maximum ice advance occurred late (i.e., during Marine Isotope Stage 2) compared to the chronology currently established for the rest of the Pyrenees. Despite debatable evidence for a glacial readvance during the Oldest Dryas stade, ice-cap melt-out was rapid, residual cirque glaciers having disappeared by the Allerød interstade. This is consistent both with North Atlantic excursions established by the Greenland ice cores and paleoenvironmental data for the region. The rapid response of the east-Pyrenean ice cap to temperature variations is primarily linked to its small size compared to larger Pyrenean ice fields, to the dry Mediterranean climate, and to topography-related nonlinearities in which a small vertical rise in equilibrium line altitude generates a large change in ice mass. Possible sources of age uncertainty are discussed in the context of sampling design for single-nuclide (10Be) dating of landform sequences in formerly glaciated landscapes. [Copyright &y& Elsevier]

Abstract: A compilation and a critical assessment of the 14C data set available show that the chronology of glacial events in the Pyrenees is not well constrained. After reviewing the literature on glacial reconstruction, we suggest a simplified subdivision of the Pyrenean last glacial cycle record into Last Pleniglacial, Deglaciation, and Neoglacial. To improve the numerical glacial chronology, we provide 10Be surface exposure ages for 5 glacial erosion surfaces, 9 moraines and 2 erratics in the Upper Noguera Ribagorçana Valley (south-central Pyrenees). Published corrected 14C data and new 10Be exposure ages indicate that the major phase of moraine building recorded in this valley during the Last Pleniglacial probably occurred after 25kaBP. This age calls in question the generally accepted hypothesis of a very early deglaciation of the Pyrenees ca 70–40kaBP, and strongly suggests that the Pyrenees could have been in pleniglacial conditions during the Last Glacial Maximum (LGM). However, we do not exclude the possibility that the maximum glacier extent during the last glacial cycle had taken place much earlier than the LGM, as indicated by some published U-Th, AMS 14C and OSL data. We suggest that pleniglacial conditions could have taken place during a longer (⪢30–20ka) period than generally assumed, and that the Last Pleniglacial could include several glacier fluctuations recorded irregularly in different valleys, with a last major glacier readvance taking place around the LGM. In addition, the Deglaciation is represented by a series of moraines deposited between ca 13.7±0.9 and 10.1±0.6ka. This moraine series indicates a highly variable climatic pattern that is partly correlated with Greenland Stadial 1 (the Younger Dryas), and suggests that the Deglaciation could have continued into the early Holocene. [Copyright &y& Elsevier]