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The presence of a late Quaternary ice sheet/ice shelf over the East Siberian Sea has been proposed in several papers. Here, we further document its duration/resilience based on the sedimentary, bulk mineralogical, and geochemical (organic matter content and its stable isotopic composition, U‐Th series) properties of a core raised from the southernmost Mendeleev Ridge. The chronostratigraphy of the studied core was mainly built from the 230Th excess (230Thxs) distribution and decay downcore. At the core‐top, peaking 230Thxs values during the early MIS 3 and mid‐MIS 1 encompassing an MIS 2 hiatus were observed. As documented in several papers, these peaks suggest seasonally open ice conditions over proximal continental shelves. Below, the interval spanning MIS 4 and possibly MIS 5d records major ice‐rafting events illustrated by overall high coarse‐fraction contents. Underlying MIS 5e, down to MIS 11, the sediment depicts relatively low sand (1.7±2.5 dw%), high clay (33.5±4.7 dw%), and very low organic carbon (0.10±0.06 dw%) contents, and low δ13Corg values (−24.3±0.9‰). This section is interpreted as recording fine sediment transport by deep currents and/or meltwater plumes below a resilient ice cover, only interrupted by a few short‐duration events. These events include (i) detrital carbonate pulses assigned to deglacial events along the NW Laurentide Ice Sheet margin (Termination (T) III), and (ii) intervals with some planktonic foraminifer occurrences, likely relating to their advection from open areas of the Arctic Ocean (MIS 5e, 9 and 11). All Terminations, but TII and the early MIS 3, show peaking Mn/Al values linked to the submergence of Arctic shelves under a rising sea level. We conclude that the resilient ice cover, likely an ice shelf, has been present over the southern Mendeleev Ridge during most of the interval after the Mid‐Pleistocene Transition and was favoured by the low summer insolation of the MIS 14 to 10 interval. [ABSTRACT FROM AUTHOR]

Arnold, L. J., Roberts, R. G., MacPhee, R. D. E., Haile, J. S., Brock, F., Möller, P., Froese, D. G., Tikhonov, A. N., Chivas, A. R., Gilbert, M. T. P. & Willerslev, E. 2010: Paper II - Dirt, dates and DNA: OSL and radiocarbon chronologies of perennially frozen sediments in Siberia, and their implications for sedimentary ancient DNA studies. Boreas, Vol. 40, pp. 417-445. 10.1111/j.1502-3885.2010.00181.x. ISSN 0300-9483 The sedimentary ancient DNA ( sedaDNA) technique offers a potentially invaluable means of investigating species evolution and extinction dynamics in high-latitude environments. An implicit assumption of the sedaDNA approach is that the extracted DNA is autochthonous with the host deposit and that it has not been physically transported from older source deposits or reworked within the sedimentary profile by postdepositional mixing. In this paper we investigate whether these fundamental conditions are upheld at seven perennially frozen wetland sites across the Taimyr Peninsula and coastal lowlands of north-central Siberia. Optically stimulated luminescence (OSL) and radiocarbon (C) dating are used to constrain the ages of both the inorganic and organic fractions of perennially frozen deposits from which sedaDNA of extinct and extant species have been recovered. OSL and C age/depth profiles, as well as single-grain equivalent dose (D) distribution characteristics, are used to assess the stratigraphic integrity of these sedaDNA sequences by (i) identifying the presence of primary or reworked organic and inorganic material, and (ii) examining the types of depositional and postdepositional processes that have affected specific sedimentary facies. The results of this study demonstrate that even though DNA preservation and stratigraphic integrity are commonly superior in perennially frozen settings, this does not, in itself, guarantee the suitability of the sedaDNA approach. The combined OSL and C chronologies reveal that certain perennially frozen sites may be poorly suited for sedaDNA analysis, and that careful site selection is paramount to ensuring the accuracy of any sedaDNA study - particularly for 'latest appearance date' estimates of extinct taxa. [ABSTRACT FROM AUTHOR]

Arnold, L. J. & Roberts, R. G. 2011: Paper I - Optically stimulated luminescence (OSL) dating of perennially frozen deposits in north−central Siberia: OSL characteristics of quartz grains and methodological considerations regarding their suitability for dating. Boreas, Vol. 40, pp. 389-416. 10.1111/j.1502-3885.2011.00209.x. ISSN 0300−9483. Optically stimulated luminescence (OSL) dating of coarse-grained quartz is increasingly being used as the main chronological tool in late Quaternary palaeoenvironmental reconstructions of Siberia. However, relatively little information has been published on the suitability of OSL dating for the various types of perennially frozen sediments found in this region. Here we provide a systematic examination of the quartz luminescence characteristics of 21 perennially frozen samples from the Taimyr Peninsula and adjacent coastal lowlands of north-central Siberia, and discuss their implications for the reliability of single-grain and multi-grain OSL chronologies in such contexts. The results of this study suggest that the quartz luminescence characteristics of these samples are, in principle, favourable for OSL dating but, in practice, require that a series of validation checks are made of the chosen experimental conditions. If these tests are satisfied, then reliable OSL chronologies should be obtained for sedimentary deposits in this region. Importantly, however, the single-grain and multi-grain aliquot equivalent dose (D) distribution characteristics for our samples reveal that there are advantages in targeting certain types of depositional settings for OSL dating studies of Siberian sediments. We also show that samples from the same depositional settings, and even from the same sites, do not necessarily display similar D distribution characteristics. The latter complication favours the use of single-grain analysis to unravel the bleaching and burial histories of young (mid- to late Holocene) sediments in these Arctic environments. [ABSTRACT FROM AUTHOR]

The principal aim of this paper is to present a critical overview of the stratigraphical subdivision and correlation of the Late Mid‐Pleistocene (LMP) sediments in Lithuania. In recent decades, a number of studies of LMP sediments have been carried out, allowing clarification of the stratigraphical position of individual sedimentary sections. Particular efforts have been made to determine the age of sediments using a variety of absolute age determination methods. However, there are still several outstanding questions. It is still unclear how many warm periods occurred during the Saalian in Lithuania and of what magnitude. The least problematic issue is identification of the Butėnai (Holsteinian) Interglacial as it correlates well biostratigraphically with the contemporaneous sections of adjacent areas. The most controversial unit is the Snaigupėlė Interglacial, the age of which continues to be a subject of debate. Recently, more evidence has emerged that the sediments considered to be of the Snaigupėlė Interglacial are contemporaneous with the Merkinė (Eemian) Interglacial. The chronological placement of these sediments closely hinges on the unresolved stratigraphical classification of the Medininkai deposits (MIS 6 or MIS 8?) and the Žemaitija tills (MIS 8 or MIS 10?). The debate is centred on whether these two tills were formed during two entirely different glaciations or represent different phases of a single major glaciation event. Traditionally, these two tills were attributed to distinct glaciation events separated by the Snaigupėlė Interglacial. However, no sedimentary sections have been discovered that contain both these tills and the interglacial sediments that separate them. Given the similar lithological, geochemical and petrographic composition of the Medininkai and Žemaitija tills some research has supported their possible stadial rank. The clarification of these stratigraphical issues in the future may be facilitated by the application of new proxies and re‐examination of the existing LMP key sections. [ABSTRACT FROM AUTHOR]

Simple cutting devices such as used in the printing industry allow precise and fine sectioning of frozen peats and sediments, thus enabling research with high temporal resolution. Large slices are useful in the collection of multiple synchronous subsamples for multidisciplinary research. This article describes the apparatus (called DAMOCLES) and its operation, and presents some examples from practice. These include combined microfossil, macrofossil and chemical analyses of the same sample with a sample resolution of 0.5 cm (temporal resolution c. 1 year): rapid changes occur that would have remained unnoticed with a coarser sampling distance. The final example presents a sample resolution of only 0.5 mm. These examples illustrate the possible uses of the DAMOCLES apparatus in palaeoecological research. [ABSTRACT FROM AUTHOR]

Studies of the upper 447 m of the DEEP site sediment succession from central Lake Ohrid, Balkan Peninsula, North Macedonia and Albania provided important insights into the regional climate history and evolutionary dynamics since permanent lacustrine conditions established at 1.36 million years ago (Ma). This paper focuses on the entire 584‐m‐long DEEP sediment succession and a comparison to a 197‐m‐long sediment succession from the Pestani site ~5 km to the east in the lake, where drilling ended close to the bedrock, to unravel the earliest history of Lake Ohrid and its basin development. 26Al/10Be dating of clasts from the base of the DEEP sediment succession implies that the sedimentation in the modern basin started at c. 2 Ma. Geophysical, sedimentological and micropalaeontological data allow for chronological information to be transposed from the DEEP to the Pestani succession. Fluvial conditions, slack water conditions, peat formation and/or complete desiccation prevailed at the DEEP and Pestani sites until 1.36 and 1.21 Ma, respectively, before a larger lake extended over both sites. Activation of karst aquifers to the east probably by tectonic activity and a potential existence of neighbouring Lake Prespa supported filling of Lake Ohrid. The lake deepened gradually, with a relatively constant vertical displacement rate of ~0.2 mm a−1 between the central and the eastern lateral basin and with greater water depth presumably during interglacial periods. Although the dynamic environment characterized by local processes and the fragmentary chronology of the basal sediment successions from both sites hamper palaeoclimatic significance prior to the existence of a larger lake, the new data provide an unprecedented and detailed picture of the geodynamic evolution of the basin and lake that is Europe's presumed oldest extant freshwater lake. [ABSTRACT FROM AUTHOR]

At the Pingorsuit Glacier in North‐West Greenland, an organic‐rich deposit that had recently emerged from the retreating ice cap was discovered at an elevation of 480 m above sea level. This paper reports on macrofossil analyses of a coarse detritus gyttja and peaty soil, which occurred beneath a thin cover of till and glacifluvial deposits. The sediments contained remains of vascular plants, mosses, beetles, caddisflies, midges, bryozoans, sponges and other invertebrates. The flora includes black spruce, tree birch, boreal shrubs and wetland and aquatic taxa, which shows that mires, lakes and ponds were present in the area. We describe a new extinct waterwort species Elatine odgaardii. The fossils were deposited in a boreal environment with a mean July air temperature that was at least 9 °C higher than at present. The fossil assemblages show strong similarities with others from Greenland that have been assigned an Early Pleistocene age, and we suggest a similar age for the sediments found at the margin of the Pingorsuit Glacier. At the Pingorsuit Glacier in North‐West Greenland, an organic‐rich deposit was discovered at an elevation of 480 m above sea level. The sediments contained remains of vascular plants, mosses, beetles, caddisflies, midges, bryozoans, sponges and other invertebrates. The fossils were deposited in a boreal environment with a mean July air temperature that was at least 9 °C higher than at present. [ABSTRACT FROM AUTHOR]

This paper provides a new deglacial chronology for retreat of the Irish Ice Sheet from the continental shelf of western Ireland to the adjoining coastline, a region where the timing and drivers of ice recession have never been fully constrained. Previous work suggests maximum ice‐sheet extent on the outer western continental shelf occurred at ~26–24 cal. ka BP with the initial retreat of the ice marked by the production of grounding‐zone wedges between 23–21.1 cal. ka BP. However, the timing and rate of ice‐sheet retreat from the inner continental shelf to the present coast are largely unknown. This paper reports 31 new terrestrial cosmogenic nuclide (TCN) ages from erratics and ice‐moulded bedrock and three new optically stimulated luminescence (OSL) ages on deglacial outwash. The TCN data constrain deglaciation of the near coast (Aran Islands) to ~19.5–18.5 ka. This infers ice retreated rapidly from the mid‐shelf after 21 ka, but the combined effects of bathymetric shallowing and pinning acted to stabilize the ice at the Aran Islands. However, marginal stability was short‐lived, with multiple coastal sites along the Connemara/Galway coasts demonstrating ice recession under terrestrial conditions by 18.2–17. ka. This pattern of retreat continued as ice retreated eastward through inner Galway Bay by 16.5 ka. South of Galway, the Kilkee–Kilrush Moraine Complex and Scattery Island moraines point to late stage re‐advances of the ice sheet into southern County Clare ~14.1–13.3 ka, but the large errors associated with the OSL ages make correlation with other regional re‐advances difficult. It seems more likely that these moraines are the product of regional ice lobes adjusting to internal ice‐sheet dynamics during deglaciation in the time window 17–16 ka. [ABSTRACT FROM AUTHOR]

The Quaternary pteropod records published in the late 1990s from the Indian Ocean provided vital information on past oceanographic and climatic changes in this region. This paper reviews the published work on pteropod preservation and abundance in the Indian Ocean to evaluate the usefulness of this microfossil group in palaeoceanographic reconstructions. Their aragonitic shell chemistry makes them reliable indicators of ocean acidification, paleaoceanography and paleoclimate. An increased interest in studying this faunal group has arisen from recent findings on the vulnerability of aragonite shell preservation to human impacted water column chemistry changes. The compiled pteropod studies show that most of the pteropod databases contain information on abundance and distribution. However, the biogeochemical parameters and processes, such as aragonite production in the water column, their settling fluxes and the shell dissolution patterns are less explored. Despite the wide geographical range of pteropods and their significance in the marine food web, the ecology and taxonomy of the holoplanktonic gastropods in the Indian Ocean are poorly known. Though these pteropods are recovered in plankton tows (standing crop) and sediment traps (settling fluxes), the surface sediments in large parts of the northern Indian Ocean are completely devoid of them. Thus, assessing their fate in the water column and the sediment–water interface and their response to prevailing biogeochemical conditions are worth pursuing. Genomic studies and isotopic and elemental chemistry of living and fossil pteropods could help assess their response to ecological changes. To date, such modern techniques have been little utilized in studying Indian Ocean pteropods. A knowledge of their shell chemistry is crucial in the context of increased input of anthropogenic CO2 and the susceptibility of pteropod preservation to changing climate. [ABSTRACT FROM AUTHOR]

This paper presents two new pollen records and quantitative climate reconstructions from northern Chukotka documenting environmental changes over the last 27.9 ka. Open tundra‐ and steppe‐like habitats dominated between 27.9 and 18.7 cal. ka BP. Betula and Alnus shrubs might have grown in sheltered microhabitats but disappeared after 18.7 cal. ka BP. Although the climate was rather harsh, local herb‐dominated communities supported herbivores as is evident by the presence of coprophilous spores in the sediments. The increase in Salix and Cyperaceae ~16.1 cal. ka BP suggests climate amelioration. Shrub Betula appeared ~15.9 cal. ka BP, and became dominant after ~15.52 cal. ka BP, whilst typical steppe communities drastically reduced. Very high presence of Botryococcus in the Lateglacial sediments reflects widespread shallow habitats, probably due to lake level increase. Shrub Alnus became common after ~13 cal. ka BP reflecting further climate amelioration. Simultaneously, herb communities gradually decreased in the vegetation reaching a minimum ~11.8 cal. ka BP. A gradual decrease of algae remains suggests a reduction of shallow‐water habitats. Shrubby and graminoid tundra was dominant ~11.8–11.1 cal. ka BP, later Salix stands significantly decreased. The forest‐tundra ecotone established in the Early Holocene, shortly after 11.1 cal. ka BP. Low contents of green algae in the Early Holocene sediments likely reflect deeper aquatic conditions. The most favourable climate conditions were between ~10.6 and 7 cal. ka BP. Vegetation became similar to the modern after ~7 cal. ka BP but Pinus pumila came to the Ilirney area at about 1.2 cal. ka BP. It is important to emphasize that the study area provided refugia for Betula and Alnus during MIS 2. It is also notable that our records do not reflect evidence of Younger Dryas cooling, which is inconsistent with some regional environmental records but in good accordance with some others. [ABSTRACT FROM AUTHOR]

Low field magnetic susceptibility (MS) records of 13 reference boreholes representing the whole Quaternary fluvial succession of the Great Hungarian Plain were correlated to develop regional stratigraphy. Data from 12 of the boreholes were published between 2016 and 2020, the Tiszainoka borehole is newly reported in this paper. Eleven magnetic susceptibility cycles, capped by the most emergent master MS peaks (MP) and bordered by susceptibility termination surfaces, have been correlated. Supported by the already evaluated palaeomagnetic reversals and instability events, MPs have been correlated to the cold stages of the Marine Isotope Stage (MIS) records. MPs represent MIS 104, 100, 98, 82, 60, 52, 34(−36) and 26 of increased heavy oxygen isotope value, constituting the significant Early Pleistocene glaciations, and MIS 18, 16, 12, 8, 6 and 2 mostly representing the substantial Middle and Upper Pleistocene European glaciation events. The interpretation of early postglacial fluvial MS maxima, which emphasizes the escape of weathering‐sensitive magnetic minerals from the catchment area triggered by the thawing of mountain permafrost, is confirmed by the correlation of MPs to the changes of the global ice volume. As a result, fluvial MS records can be considered as a proxy for mountain permafrost development in the catchment areas. Regional correlations confirmed that the Körös and Jászság Basins and the Makó Trough are sites of almost continuous fluvial records of the past 2600 ka. Thus, the Pannonian Quaternary fluvial succession is sufficiently complete to provide a satisfactory record of mountain permafrost development of the Alp‐Carpathian region, the latter being a globally relevant European representative of mid‐latitude mountain regions. The similarity of the Pannonian fluvial MS succession as a permafrost proxy to the marine ice‐rafted detritus (IRD) and Chinese loess/palaeosol MS records promises the possibility of comparative investigations of globally relevant proxy records and mid‐latitude mountain permafrost development. [ABSTRACT FROM AUTHOR]

The Pleistocene biochronology of Ukraine based on remains of small mammals was established in the late 20th century. The main biochronological criteria used at that time were based on temporal changes in the fauna composition and percentage differences between teeth morphotypes in voles (Arvicolidae). In the present paper, these criteria are supplemented by morphometric data of the occlusal surface and enamel thickness of the first lower molars. The obtained numerical indices allowed evolutionary changes for particular taxa within Arvicolidae during the Pleistocene to be established. Evolutionary changes within particular lineages (Allophaiomys‐Microtus s.l., Mimomys‐Arvicola, Borsodia‐Prolagurus‐Lagurus) are discussed. The chronological sequence of about 70 Pleistocene sites in Ukraine and adjacent countries was described based on using both old and new criteria and taking into account cyclic climatic changes. We use and update biochronological units, i.e. faunal assemblages (formerly faunal complexes), which are divided into several associations (composition of arvicolid taxa at a particular evolutionary level in reference faunas). Further correlation of Pleistocene deposits is also possible since some marine sediments in the territory of Ukraine contain arvicolid remains. [ABSTRACT FROM AUTHOR]

This paper presents the results of high‐resolution sedimentological analyses of sediment cores from the eastern Gulf of Finland (Baltic Sea). Sampling sites in the periphery of sedimentary basins were selected on the basis of acoustic profiling analyses. The research allowed tracing of the transition from the freshwater Ancylus Lake to the Littorina Sea. A specific transitional layer of 'blue clays', indicating the first stage of brackish water inflow into the Gulf of Finland, was dated to 9.1 ka BP. The date of first appearance of Littorina silty clay sedimentation was as follows: from 8.0 ka BP near Gogland Island, from 7.0 ka BP near Moshchny Island and from 5.9 ka BP near the Berezovye Islands. Holocene cycles of hypoxia, associated with periods of warming, were identified and cycles of 'warming – transgression – anoxic conditions' and 'cooling – regression – oxygen‐rich conditions' were revealed. During the first stage of Littorina transgression (8.0–7.0 ka BP), the near‐bottom environment in the deepest sedimentary basin of the eastern Gulf of Finland was characterized by oxygen deficiency. In contrast, 7.0–6.0 ka BP was dominated by oxygen‐rich conditions and active processes of bioturbation. Anoxic conditions occurred again from 6.0–4.8 ka BP (Holocene Climatic Optimum), resulting in the accumulation of undisturbed silty clays with subhorizontal lamination. The interval from 4.8–2.0 ka was then characterized by oxygen‐rich near‐bottom conditions favourable for benthic organisms. The grain‐size distributions throughout the sediment cores from the easternmost sedimentary basins suggest a relative lowering of the sea level from 3.5–1.8 ka and a rise after 1.8 ka BP. [ABSTRACT FROM AUTHOR]

This paper presents an age–depth model based on an ultra‐high‐resolution, 80‐m‐thick sedimentary succession from a marine continental shelf basin, the Kattegat. This is an area of dynamic deglaciation of the Fennoscandian Ice Sheet during the Late Pleistocene. The Kattegat is also a transitional area between the saline North Sea and the brackish Baltic Sea. As such, it records general development of currents and exchange between these two systems. Data for the succession were provided through the Integrated Ocean Drilling Program Site M0060. The site indicates onset of deglaciation at c. 18 ka BP and relatively continuous sedimentation until 13 ka BP. At this point, sediments record a hiatus until c. 9–7 ka BP. The uppermost sedimentary unit contains redeposited material, but it is estimated to represent only the last c. 9–7 ka BP. The age–depth model is based on 17 select, radiocarbon‐dated samples and is integrated with a set of physical and chemical proxies. The integrated records provide novel constraints on the timing of major palaeoenvironmental changes, such as the transition from glaciomarine proximal to glaciomarine distal and marine conditions, and their connections to known major events and processes in the region and the North Atlantic. Depositional evidence specifically documents connections between the Fennoscandian Ice Sheet behaviour and atmospheric and oceanic warming. Glacial retreat may have also depended on topographic factors such as changes in basin width and depth, linked to relative sea level changes and land uplift. The results indicate an early response of the Fennoscandian Ice Sheet to changing climate, and the ice sheet's possible influence on oceanic circulation during the Late Pleistocene deglaciation. [ABSTRACT FROM AUTHOR]

This paper presents a reconstruction of the marginal zone of the Anglian (Elsterian, 480–420 ka BP) age ice sheet in the Danbury‐Tiptree area, East Anglia, UK. The research area is a unique locality where the ice front abutted against a 30‐km‐long and 100‐m‐tall ridge in an otherwise lowland area. Observations from three main field localities (Danbury quarry, Royal Oak pit and Tiptree quarry) are complemented with ground penetrating radar survey data, borehole data analysis, laboratory analyses and geological map interpretation. A four‐stage model of the evolution of the landscape in the Danbury‐Tiptree area is presented. The results are of broader importance, in that the sedimentary record sheds light on the processes operating at a constrained ice‐sheet margin. The paper identifies the most important characteristics of the depositional environments at an ice front terminating within this type of setting: (i) high temporal and spatial variability of energetic depositional conditions, resulting in the presence of a vast array of distinct depositional sub‐environments; (ii) mechanisms promoting differential erosion leading to enhanced topography, and (iii) unusually high overburden pressure in the topographically constrained ice margin within the otherwise lowland area influencing the ice‐sheet–bedrock interaction in this particular research area, inducing postglacial seismicity. [ABSTRACT FROM AUTHOR]

This paper presents a study of past coastline dynamics and their consequences for prehistoric societies living in the glacio‐isostatically uplifted central Limfjord area, northern Denmark. The consequences of the gradual relative sea level (RSL) changes have been investigated to develop a local RSL curve, study settlement patterns on newly exposed marine foreland, and estimate changes in the area and quality of grazing and forage for livestock. This was achieved by a multidisciplinary approach involving existing regional and local beach ridges dated by optically stimulated luminescence, a comprehensive database of archaeological finds, and extrapolation based on a digital elevation model. The beach‐ridge dates suggested a near‐linear local RSL change in the study area of ~1.2±0.2 m per 1000 years for the last 3000 years. Based on this, a palaeo‐coastline development model was produced that correlated well with a comprehensive database of archaeological finds. The model indicates that (i) few human settlements moved to the newly exposed marine foreland prior to modern times, though clusters of burial mounds (barrows) suggest that some of the new lands were colonized during the Late Roman Iron Age until 400 CE, (ii) winter‐flooded marine foreland with high‐quality livestock grazing increased steadily until c. 750 CE and then remained stable at approximately 150 km2, and (iii) due to high salinity of the inundating water, the palaeo‐Limfjord probably had Wadden Sea‐like fertile saltmarshes until c. 1 CE. The improved chronologies yield a better understanding of the spatial and temporal prehistoric human–nature interactions in the study area. The findings highlight the need for accurate local RSL curves in order to interpret concomitant terrestrial environment drivers and trajectories, and thereby understand causal relationships and consequences for prehistoric human–environment interactions in coastal areas. [ABSTRACT FROM AUTHOR]

This paper presents evidence for a limnological response to the Laacher See eruption (LSE) as detected in lake sediments from Nahe, northern Germany. The sediment section of the Allerød period dating to between 13 422 and 12 708 cal. a BP is preserved in annual laminations. Within this section, the LSE was identified as a cryptotephra layer (12 944±44 cal. a BP). Microfacies analysis, continuous high‐resolution geochemical measurements and pollen analyses enabled a high‐resolution reconstruction of environmental change. The older part of the Allerød (c. 13 422 to 12 943 cal. a BP) was characterized by relatively stable sedimentation conditions. Evidence for windier conditions dating to c. 13 160 to 13 080 cal. a BP probably reflects the Gerzensee oscillation. Pronounced changes of the lake sedimentation followed the LSE. Four unusually thick varves with increased amounts of allochthonous material indicate serious disturbance of the local environment immediately after the LSE, related to increased storminess and/or the occurrence of high intensity rainfall events. A pronounced reduction of biogenic silica accumulation for c. 60 years after the LSE could reflect a period of acidification. Indications of a simultaneous lake level increase until c. 60 years after the LSE are in line with the supposed reduced evapotranspiration associated with cooler conditions. About 120 years after the LSE, increased oxygen access at the lake bottom, allochthonous input and Cl fluxes point to an onset of increasingly stronger westerly winds, probably as a long‐term response to the LSE. This supports the idea of a southward shift of the mid‐latitude westerlies wind system within the interval between the LSE and the beginning of the Younger Dryas. The pace of the southwards shift of this wind system decreased from 10 km a−1 in the initial phase (40–120 years after LSE) to 6 km a−1 in the later phase (120–200 years after LSE). [ABSTRACT FROM AUTHOR]

The thick loess deposits in Tajikistan are important archives for palaeoclimatic reconstruction in Central Asia during the Quaternary. To date however, adequate high‐resolution studies of chronology and climatic evolution of the Tajik loess have still not been carried out. In this paper, chronology, dust provenance, and palaeoclimatic significance of a loess section in the centre of the Tajik Basin has been studied. Optically stimulated luminescence (OSL) dating yields ages ranging from ~60.8 to 0.8 ka, indicating that this loess section accumulated during the Last Glacial period and the Holocene. The provenance of the Tajik loess includes dust transported by westerly winds from the upwind deserts in Turkmenistan, and minor proximal particles derived from alluvial sediments of the nearby mountains and fluvial/glacifluvial deposits on the river flood‐plains. Multiple palaeoclimatic proxies including colour, particle size, environmental magnetic parameters, and element concentrations together with their correlation with the deep‐sea δ18O record suggest that the Tajik loess accumulated during cold and dry stadial periods, while palaeosols formed during warm and moist interglacials or interstadials, which is similar to the Chinese Loess Plateau. Although the two regions have different dust provenances and wind systems, such similarity indicates that the palaeoclimatic variations in both regions might be forced by a common global factor, e.g. the global ice volume. Variations in global ice volume influenced the climate in Tajikistan and the Loess Plateau through affecting the westerlies and the East Asian Monsoon, respectively. [ABSTRACT FROM AUTHOR]

During the Last Glacial cycle (MIS 4 to MIS 2), the isthmic Pyrenees mountain range acted as a biogeographical barrier, effectively restricting faunal exchanges to its western and eastern terminations. The study of the composition of megaherbivore communities has revealed the transitional character of the Cantabrian region (northwest Iberian Peninsula) during the MIS 3, between western European cold faunas and southern Iberian temperate faunas. In the Catalan area (northeastern Iberian Peninsula), cold‐adapted faunas are frequently recorded during the cold pulses of MIS 3 and MIS 2, albeit to a lesser extent. In the present paper, we provide the first direct evidence of a muskox record in the Iberian Peninsula, together with a morphometric study and the results of collagen δ13C and δ15N analysis. The results reveal that the Arbreda specimen fits biometrically within the Late Holocene Umingmak specimens (Banks Island, Canada). Moreover, its isotopic values fall into the range of Late Pleistocene Mammoth steppe muskoxen, which indicates a typical ecological behaviour for muskox. Indeed, it suggests a niche partitioning of this cold‐adapted specimen in relation to other Gravettian Iberian fauna. Chronologically, this occurrence is interpreted as an isolated southward expansion of the biogeographical limits of muskox during the Greenland Stadial 4, in the latest MIS 3. [ABSTRACT FROM AUTHOR]

Holocene relative shore level (RSL) changes and Stone Age palaeogeography of Hiiumaa Island are reconstructed using airborne LiDAR elevation data, sedimentological and archaeological proxies as well as GIS‐based landscape modelling. Altogether, 38 RSL index and limiting points are used in modelling and presented in the current paper. The highest raised shorelines of the Ancylus Lake and Litorina Sea, mapped at the elevations of 47 and 26 m a.s.l., formed around 10.3 and 7.4 cal. ka BP, respectively. The reconstructed RSL curve reveals a 20‐m drainage of Ancylus Lake followed by a land‐uplift‐driven 3‐m regression during the Initial Litorina Sea period. RSL rise during the Litorina Sea transgression remained below 4 m and its maximum was reached later than proposed previously, discarding therefore the idea of highly diachronous Litorina culmination in the eastern Baltic Sea. During the period 7.4–6.0 cal. ka BP,RSL fall was about 4.3 mm a−1, and afterwards in average at about 1 mm‐1 less suggesting deceleration in isostatic rebound. suggesting deceleration in isostatic rebound. Palaeogeographical reconstructions show that during its earliest occupation at about 7.6 cal. ka BP less than 1% of the terrain of Hiiumaa was above the sea level and that wind‐protected SE exposed shores were the most preferred campsite locations of Late Mesolithic and Neolithic settlers. These campsites are located successively at lower elevations following the shoreline retreat and show repeated use of this coastal area between 7.6 and 4.6 cal. ka BP. Due to the spread of the Corded Ware culture around 4.8–4.0 cal. ka BP the settlements of Hiiumaa Island and many other coastal areas of the eastern Baltic moved from the coast to more suitable places for agriculture and animal husbandry. [ABSTRACT FROM AUTHOR]

No agreement on what constitutes a safe and reproducible anticontamination protocol exists for ancient starch research. Protocols applied to laboratory work may represent 'symptomatic treatment' only, as contamination of archaeological materials in the field may be more extensive than realized. This paper is the first systematic study on the impact that modern starches from surface and buried soils, windborne dispersal, human motion, excavation techniques and toolkits, and field attire has on archaeological sample quality. The study area is Olduvai Gorge, Tanzania. We identify seven starch types (discrete granules, n = 788) that embody the starch contamination landscape for the region. This study also demonstrates the various diagenetic changes that buried starch granules undergo in a short time, such as cavitation, fissuring, disruption and gelatinization. There are significant differences in morphotype class representation between the topsoil starches and those collected deeper below ground at excavated sites. Diagenetically transformed granules from underground storage organs dominate in soils, while native starches from cereal endosperm (Panicoideae and Triticeae) abound above ground in airborne samples. Furthermore, we illustrate how lithic samples excavated under standard field conditions can be contaminated, and that when a sample is compromised during excavation, it may be impossible to distinguish between target and introduced starches, especially when granules are identical or morphologically similar. The paper provides field recommendations to control false positives. [ABSTRACT FROM AUTHOR]

In this paper, we present the results of new archaeological and geological research carried out in SHK Extension, a new site excavated within the SHK fluvial complex (Bed II, Olduvai Gorge). The paper describes the stratigraphy of the site and its correlation with our excavation in SHK Main Site, showing that overbank archaeological accumulations in both areas are synchronous and form part of the same fluvial palaeo-landscape. On the basis of the archaeo-stratigraphical analysis performed, mainly geared towards defining high-resolution chrono-stratigraphical frameworks within the deposit, we report the results of a technological study of the lithic collection sorted by archaeo-units, an assessment of the integrity of the main accumulation and an exhaustive lithic refitting programme. The archaeological sequence at SHK Extension, consisting of three archaeo-units, preserves a high-density patch of lithics and fossil bones (Level B2), on an overbank setting, isochronous with the SHK Main site. The high percentage of small lithic remains and bones, large number of fresh archaeological materials, and the identification of several refit sets support the integrity of the anthropogenic accumulation documented in Level B2. The main technological trait of the lithic assemblage from this level is the preservation of a qualitatively significant sample of large flakes and LCTs. The technological behaviours observed in SHKE, in the framework of the SHK complex, confirm that the complex web of inter-assemblage variability during Bed II times operated also in very close fractions of the same palaeo-landscape. This reinforces the idea that subtle functional parameters must be taken into account in our current assessment of the Developed Oldowan/Acheulean interface. [ABSTRACT FROM AUTHOR]

Despite numerous palaeoenvironmental investigations of loess–palaeosol sequences across the Carpathian Basin, well‐dated high‐resolution records are scarce. This paper presents a new high‐resolution chronology for the loess‐palaeosol sequence at Surduk (Serbia), based on optically stimulated luminescence (quartz) and post‐infrared infrared stimulated luminescence (polymineral) dating. The presented record spans 53–19 ka, with primary loess deposition occurring after 52±2 ka, and differs from previously published chronologies that relied on less precise and now superseded dating protocols. Based on the new chronology, mass accumulation rates (MARs) for Surduk were constructed and compared with sites in the Carpathian Basin. The results demonstrate that accumulation periods across this area are not consistent in timing or rates. The high‐resolution dating strategy identifies a disturbance in sediment deposition that occurred after 45±2 ka and implies that site contains a hiatus. Finally, we show samples that failed routine dose recovery and preheat plateau tests, and had low fast ratios. Supported by bulk sample geochemical analysis it is proposed that a potential abrupt source shift, during the Last Glacial Maximum, may be the cause of the anomalous luminescence behaviour. [ABSTRACT FROM AUTHOR]

Large, ice‐marginal lakes that were impounded by the maximally extended Cordilleran Ice Sheet (CIS) provided source waters for the extraordinarily large floods that formed the Channeled Scabland of Washington and Idaho, USA. However, flood flows that drained CIS meltwater and contributed to landscape evolution during later stages of deglaciation have hitherto been poorly investigated. This paper provides the first evidence for such a late deglacial floodwater source: glacial Lake Purcell (gLP). Sedimentary evidence records the northward extension of gLP from Idaho, USA into British Columbia, Canada and establishes its minimum palaeogeographical extent. Sedimentary evidence suggests that the deglacial Purcell Lobe was a capable ice dam that impounded large volumes of gLP water. A review of glacio‐isostatically affected lakes during CIS deglaciation suggests that gLP could have been subjected to tilts ranging from 0 to >1.25 m km−1. Sedimentary evidence suggests high lake plane tilts (⪆1.25 m km−1) are the most likely to have affected gLP. Using this, the palaeogeography and volume of gLP are modelled, revealing that ~116 km3 of water was susceptible to sudden drainage into the Channeled Scabland via the Columbia River system. This calculation is supported by sedimentary and geomorphic evidence compatible with energetic flood flows along the gLP drainage route and suggests gLP drained suddenly, causing significant landscape change. [ABSTRACT FROM AUTHOR]

Younger Dryas ice‐marginal ('hummocky') moraines in Scotland represent valuable terrestrial archives that can be used to obtain important information on ice‐marginal dynamics and glacier thermal regimes during a period of rapid climatic change. In this paper, we present detailed sedimentological studies of Younger Dryas ice‐marginal moraines in the Gaick, central Scotland, the former site of a spatially restricted plateau icefield. Exposures demonstrate that moraines in the Gaick represent terrestrial ice‐contact fans, with evidence of proglacial and subglacial glaciotectonization, as reported elsewhere in Scotland. The exposures also reveal the influence of local hydrogeological conditions, with pressurization of the groundwater system leading to the formation of hydrofracture fills within some moraines. Clast shape analysis shows that all the moraines contain debris consistent with transport in the subglacial traction zone. The sedimentological data, and the planform arrangement of the moraines as nested arcs or chevrons, indicate that retreat of the Younger Dryas Gaick Icefield outlets was incremental and oscillatory. This evidence strongly suggests a mainly temperate thermal regime and short glacier response times, but with narrow cold‐ice zones near the margins facilitating the elevation of basal debris to the glacier surface. Analogous glaciodynamic regimes occur at modern ice‐cap and plateau icefield outlets in Iceland and Norway, although there are significant differences in the nature of ice‐marginal deposition. The glaciodynamic signature recorded by moraines in the Gaick has allowed us to shed new light on the ice‐marginal dynamics and thermal regime of one of the most easterly Younger Dryas icefields in Scotland. [ABSTRACT FROM AUTHOR]

Eskers are useful for reconstructing meltwater drainage systems of glaciers and ice sheets. However, our process understanding of eskers suffers from a disconnect between sporadic detailed morpho‐sedimentary investigations of abundant large‐scale ancient esker systems, and a small number of modern analogues where esker formation has been observed. This paper presents the results of detailed field and high‐resolution remote sensing studies into two esker systems that have recently emerged at Hørbyebreen, Svalbard, and one at Breiðamerkurjökull, Iceland. Despite the different glaciological settings (polythermal valley glacier vs. active temperate piedmont lobe), in all cases a distinctive planform morphology has developed, where ridges are orientated in two dominant directions corresponding to the direction of ice flow and the shape of the ice margin. These two orientations in combination form a cross‐cutting and locally rectilinear pattern. One set of ridges at Hørbyebreen is a hybrid of eskers and geometric ridges formed during a surge and/or jökulhlaup event. The other sets of ridges are eskers formed time‐transgressively at a retreating ice margin. The similar morphology of esker complexes formed in different ways on both glacier forelands implies equifinality, meaning that care should be taken when interpreting Quaternary esker patterns. The eskers at Hørbyebreen contain substantial ice‐cores with a high ice:sediment ratio, suggesting that they would be unlikely to survive after ice melt. The Breiðamerkurjökull eskers emerged from terrain characterized by buried ice that has melted out. Our observations lead us to conclude that eskers may reflect a wide range of processes at dynamic ice margins, including significant paraglacial adjustments. This work, as well as previous studies, confirms that constraints on esker morphology include: topographic setting (e.g. confined valley or broad plain); sediment and meltwater availability (including surges and jökulhlaups); position of formation (supraglacial, englacial or subglacial); and ice‐marginal dynamics such as channel abandonment, the formation of outwash heads or the burial and/or exhumation of dead ice. [ABSTRACT FROM AUTHOR]

Only a few chronological constraints on Lateglacial and Early Holocene glacier variability in the westernmost Alps have hitherto been obtained. In this paper, moraines of two palaeoglaciers in the southern Écrins massif were mapped. The chronology of the stabilization of selected moraines was established through the use of 10Be cosmic ray exposure (CRE) dating. The equilibrium line altitude (ELA) during moraine deposition was reconstructed assuming an accumulation area ratio (AAR) of 0.67. Ten pre‐Little Ice Age (LIA) ice‐marginal positions of the Rougnoux palaeoglacier were identified and seven of these have been dated. The 10Be CRE age of a boulder on the lowermost sampled moraine indicates that the landform may have been first formed during a period of stable glaciers at around 16.2±1.7 ka (kiloyears before AD 2017) or that the sampled boulder experienced pre‐exposure to secondary cosmic radiation. The moraine was re‐occupied or, alternatively, shaped somewhat before 12.2±0.6 ka when the ELA was lowered by 230 m relative to the LIA ELA. At least six periods of stable ice margins occurred thereafter when the ELA was 220–160 m lower than during the LIA. The innermost dated moraine stabilized at or before 10.9±0.7 ka. Three 10Be CRE ages from a moraine of the Prelles palaeoglacier indicate a period of stationary ice margins at or before 10.9±0.6 ka when the ELA was lowered by 160 m with respect to the end of the LIA. The presented 10Be CRE ages are in good agreement with those of moraines that have been attributed to the Egesen stadial. Assuming unchanged precipitation, summer temperature in the southern Écrins massif at ~12 ka must have been at least 2 °C lower relative to the LIA. [ABSTRACT FROM AUTHOR]

Nares Strait, a major connection between the Arctic Ocean and Baffin Bay, was blocked by coalescent Innuitian and Greenland ice sheets during the last glaciation. This paper focuses on the events and processes leading to the opening of the strait and the environmental response to establishment of the Arctic‐Atlantic throughflow. The study is based on sedimentological, mineralogical and foraminiferal analyses of radiocarbon‐dated cores 2001LSSL‐0014PC and TC from northern Baffin Bay. Radiocarbon dates on benthic foraminifera were calibrated with ΔR = 220±20 years. Basal compact pebbly mud is interpreted as a subglacial deposit formed by glacial overriding of unconsolidated marine sediments. It is overlain by ice‐proximal (red/grey laminated, ice‐proximal glaciomarine unit barren of foraminifera and containing >2 mm clasts interpreted as ice‐rafted debris) to ice‐distal (calcareous, grey pebbly mud with foraminifera indicative of a stratified water column with chilled Atlantic Water fauna and species associated with perennial and then seasonal sea ice cover) glacial marine sediment units. The age model indicates ice retreat into Smith Sound as early as c. 11.7 and as late as c. 11.2 cal. ka BP followed by progressively more distal glaciomarine conditions as the ice margin retreated toward the Kennedy Channel. We hypothesize that a distinct IRD layer deposited between 9.3 and 9 (9.4–8.9 1σ) cal. ka BP marks the break‐up of ice in Kennedy Channel resulting in the opening of Nares Strait as an Arctic‐Atlantic throughflow. Overlying foraminiferal assemblages indicate enhanced marine productivity consistent with entry of nutrient‐rich Arctic Surface Water. A pronounced rise in agglutinated foraminifers and sand‐sized diatoms, and loss of detrital calcite characterize the uppermost bioturbated mud, which was deposited after 4.8 (3.67–5.55 1σ) cal. ka BP. The timing of the transition is poorly resolved as it coincides with the slow sedimentation rates that ensued after the ice margins retreated onto land. [ABSTRACT FROM AUTHOR]

In this paper, fluvial deposits of Middle Pleistocene age in the mountain‐foreland area of southern Poland (Eastern Sudetes and Western Carpathians) are studied in order to document the evolution of fluvial systems during the coldest stages of glacial periods when the Scandinavian Ice Sheet advanced far to the south. The focus is on fluvial response to climate change and glacial impact on river system behaviour. Also considered is the tectonic uplift of the mountain part of river catchments and its potential influence on the style of fluvial sedimentation in the fore‐mountain area. Three drainage basins that were active during the Elsterian and Saalian glaciations are investigated. Facies analyses are carried out on thick successions of braided river deposits covered with till or glaciolacustrine sediments, which result in a reconstruction of the fluvial activity synchronous with the ice‐sheet advance. The results suggest that fluvial activity declined prior to ice‐sheet advance into the fore‐mountain area. This climatically induced change is directly recorded in alluvial successions by upward‐decreasing bed thicknesses and grain sizes. River longitudinal profiles were shortened in front of the advancing ice sheet. The base level of the studied rivers, created by the ice‐sheet margin, rose in parallel with glacial advance. As a result, the successive reaches of rivers (degradational, transitional, aggradational) underwent shortening and moved upstream within the catchments. Moreover, tectonically induced local increases of river slopes may have influenced the depositional processes. [ABSTRACT FROM AUTHOR]

While there are extensive macro‐ and microfossil records of a range of plants and animals from the Quaternary, earthworms and their close relatives amongst annelids are not preserved as fossils and therefore the knowledge of their past distributions is limited. This lack of fossils means that clitellate worms (Annelida) are currently underused in palaeoecological research, even though they can provide valuable information about terrestrial and aquatic environmental conditions. Their DNA might be preserved in sediments, which offers an alternative method for detection. Here we analyse lacustrine sediments from lakes in the Polar Urals, Arctic Russia, covering the period 24 000–1300 cal. a BP, and NE Norway, covering 10 700–3300 cal. a BP, using a universal mammal 16S rDNA marker. While mammals were recorded using the marker (reindeer was detected twice in the Polar Urals core at 23 000 and 14 000 cal. a BP, and four times in the Norwegian core at 11 000 cal. a BP and between 3600–3300 cal. a BP), worm extracellular DNA 'bycatch' was rather high. In this paper we present the first reported worm detection from ancient DNA. Our results demonstrate that both aquatic and terrestrial clitellates can be identified in late‐Quaternary lacustrine sediments, and the ecological information retrievable from this group warrants further research with a more targeted approach. [ABSTRACT FROM AUTHOR]

This paper presents a sedimentary record from Lake Łukie located in the southeastern part of the Central European Plain, beyond the reach of the maximum extent of the last glaciation. The lake has thermokarstic origin and developed during the last glacial termination due to subsidence of the sub‐Quaternary carbonate basement triggered by permafrost thawing. A sediment core was investigated to reconstruct water trophic state and lake depth changes during the Holocene. We aimed at showing the relationship between ecological and geochemical changes in the lake and regional/supraregional climatic and hydrological trends throughout the Holocene. Results of subfossil Cladocera analysis were combined with data on the geochemistry and stable C and O isotopes in sedimentary carbonates. Isotopic and geochemical proxies helped to detect sources of sedimentary particles in the lake and thus to reconstruct changes in the intensity of atmospheric and catchment processes (e.g. precipitation and surface runoff). The Cladocera analysis results indicated endogenic processes in the lake such as trophic changes. Our data revealed that Lake Łukie has always been a rather eutrophic water body and the periods of particularly high productivity were in the lower Preboreal and upper Subatlantic. Periods of increased water depth were recorded in the lower Preboreal, lower Boreal and upper Subboreal, whereas low water stands were obtained during the late Preboreal, late Boreal, late Atlantic and Atlantic/Subboreal transition as well as during the lower Subboreal. The sediment succession from Lake Łukie provides the first full Holocene record of carbon and oxygen stable isotopes in lacustrine carbonates from the eastern part of the Central European Lowland. The record is characterized by uncommonly high δ13C and δ18O values of the carbonates resulting from a combination of within‐lake processes and dissolution of the carbonate bedrock of Cretaceous age. The impact of the old carbonates on isotope values was helpful in the reconstruction of the catchment forcing on the lake. [ABSTRACT FROM AUTHOR]

During a pre‐site survey and construction of a new metro route and station in Copenhagen, fossiliferous organic‐rich sediments were encountered. This paper reports on multidisciplinary investigations of these organic sediments, which occurred beneath a sediment succession with a lower till, glacifluvial sand and gravel, an upper till and glacifluvial sand. The organic sediments were underlain by glacifluvial sand and gravel. The organic‐rich sediments, which were up to 0.5 m thick, accumulated in a low‐energy environment, possibly an oxbow lake. They were rich in plant fossils, which included warmth‐demanding trees and other species, such as Najas minor, indicating slightly higher summer temperatures than at present. Freshwater shells were also frequent. Bithynia opercula allowed the sediments to be put into an aminostratigraphical framework. The amino acid racemization (AAR) ratios indicate that the organic sediments formed during Marine Isotope Stage 7 (MIS 7), which is consistent with optically stimulated luminescence dating that gave ages of 206 and 248 ka from the underlying minerogenic deposit. The assemblages from Trianglen are similar to interglacial deposits from the former Free Port (1.4 km away) in Copenhagen, except that Corbicula and Pisidium clessini were not found at Trianglen. The presence of these bivalves at the Free Port and the ostracod Scottia tumida at Trianglen indicates a pre‐Eemian age. AAR data from archived Bithynia opercula from the Free Port were almost identical to those from Trianglen, indicating that the two sites are contemporary. We suggest the Trianglen interglacial be used as a local name for the MIS 7 interglacial deposits in Copenhagen. MIS 7 deposits have rarely been documented from the region, but MIS 7 deposits may have been mistaken for other ages. The use of AAR ratios in Bithynia opercula has a great potential for correlation of interglacial non‐marine deposits in mainland northern Europe. [ABSTRACT FROM AUTHOR]

This paper presents the main palaeoenvironmental results obtained from a site located in the western sector of the Beagle Channel, Isla Grande de Tierra del Fuego, southernmost Argentina. The palynological analysis performed on marine sediments from Aserradero‐Lapataia 2 (latitude 54°51′22.7″S, longitude 68°34′22.8″W) allowed us to document the evolution of palaeoenvironmental conditions during the beginning of the Holocene marine transgression into the Beagle Channel. The results indicate that, prior to the marine incursion, the coastal areas were characterized by the presence of open‐grown shrubs and herbs along with woodland palaeocommunities. The aquatic environments were dominated exclusively by freshwater taxa. Around 8300 cal. a BP, seawater gradually flooded the channel while cold and high effective moisture conditions favoured the development of an arboreal vegetation with dominance of Nothofagus forest and scarcity of shrub and herbaceous communities. Gradually increasing salinities allowed the development of freshwater/marine transitional environments indicated by aquatic palynomorphs able to tolerate stressed conditions under fluctuating salinities. The increasing dinocyst diversification with dominance of heterotrophic taxa corroborates the establishment of a fully marine environment during the middle–late Holocene in the Beagle Channel. [ABSTRACT FROM AUTHOR]

The Bristol Channel, including onshore areas, is critical for reconstructing Pleistocene glacial limits in southwest Britain. Debate about the precise regional southern limits of Devensian (Oxygen Isotope Stage (OIS) 2) and Anglian (OIS 12) glaciations has recently been rekindled. The Paviland Moraine (Llanddewi Formation), Gower, south Wales is conventionally regarded as Anglian in age. Its ‘old’ age has been based on reported highly weathered clasts, a subdued morphology and ‘field relationships’ to fossil beach sediments of now disputed age(s). Relatively little about its sedimentary characteristics has been previously published. This paper: (i) presents new sedimentological evidence including lithofacies analysis, XRF analysis and electrical resistivity tomography (ERT) of sediment cores and electrical resistivity of a tied 3D field grid; (ii) re‐assesses the proposed ‘old’ age; (iii) suggests a likely depositional origin; and (iv) discusses implications for regional glacial dynamics and future research priorities. The sediments comprise mostly dipping glacigenic diamict units containing mainly Welsh Coalfield erratics. The location and subdued moraine morphology are attributed to the hydrological influence of the underlying limestone, the local topography and ice‐sheet behaviour rather than to long‐term degradation. Moraine formation is attributed mainly to sediment gravity flows that coalesced to produce an ice‐frontal apron. Neither geochemical data nor clasts indicate prolonged subaerial weathering and in‐situ moraine sediments are restricted to a limestone plateau above and inland of fossil beach sediments. We recommend rejecting the view that the moraine represents the only recognized OIS 12 deposit in Wales and conclude that instead it marks the limit of relatively thin Last Glacial Maximum (LGM) ice in west Gower. This requires revision of the accepted view of a more restricted LGM limit in the area. We suggest that substrate hydrological conditions may be a more influential factor in moraine location and form than is currently acknowledged. [ABSTRACT FROM AUTHOR]

This paper presents the history and cryostratigraphy of the upper permafrost in the High‐Arctic Adventdalen Valley, central Svalbard. Nineteen frozen sediment cores, up to 10.7 m long, obtained at five periglacial landforms, were analysed for cryostructures, ice, carbon and solute contents, and grain‐size distribution, and were 14C‐ and OSL‐dated. Spatial variability in ice and carbon contents is closely related to the sedimentary history and mode of permafrost aggradation. In the valley bottom, saline epigenetic permafrost with pore ice down to depths of 10.7 m depth formed in deltaic sediments since the mid‐Holocene; cryopegs were encountered below 6 m. In the top 1 to 5 m, syngenetic and quasi‐syngenetic permafrost with microlenticular, lenticular, suspended and organic‐matrix cryostructures developed due to loess and alluvial sedimentation since the colder late Holocene, which resulted in the burial of organic material. At the transition between deltaic sediments and loess, massive ice bodies occurred. A pingo developed where the deltaic sediments reached the surface. On hillslopes, suspended cryostructure on solifluction sheets indicates quasi‐syngenetic permafrost aggradation; lobes, in contrast, were ice‐poor. Suspended cryostructure in eluvial deposits reflects epigenetic or quasi‐syngenetic permafrost formation on a weathered bedrock plateau. Landform‐scale spatial variations in ground ice and carbon relate to variations in slope, sedimentation rate, moisture conditions and stratigraphy. Although the study reveals close links between Holocene landscape evolution and permafrost history, our results emphasize a large uncertainty in using terrain surface indicators to infer ground‐ice contents and upscale from core to landform scale in mountainous permafrost landscapes. [ABSTRACT FROM AUTHOR]

This is a synthesis of the glacial history of the northern Urals undertaken using published works and the results of geological surveys as well as recent geochronometric and remote sensing data. The conclusions differ from the classical model that considers the Urals as an important source of glacial ice and partly from the modern reconstructions. The principal supporting evidence for the conventional model – Uralian erratics found on the adjacent plains – is ambiguous because Uralian clasts were also delivered by a thick external ice sheet overriding the mountains during the Middle Pleistocene. Alternative evidence presented in this paper indicates that in the late Quaternary the Ural mountains produced only valley glaciers that partly coalesced in the western piedmont to form large piedmont lobes. The last maximum glaciation occurred in the Early Valdaian time at c. 70–90 ka when glacial ice from the Kara shelf invaded the lowlands and some montane valleys but an icecap over the mountains was not formed. The moraines of the alpine glaciation are preserved only beyond the limits of the Kara ice sheet and therefore cannot be younger than MIS 4. More limited glaciation during MIS 2 generated small alpine moraines around the cirques of the western Urals (Mangerud et al. 2008: Quaternary Science Reviews 27, 1047). The largest moraines of Transuralia were probably produced by the outlet glaciers of a Middle Pleistocene ice sheet that formed on the western plains and discharged across the Polar Urals. The resultant scheme of limited mountain glaciation is possibly also applicable as a model for older glacial cycles. [ABSTRACT FROM AUTHOR]

The eastern England terrestrial glacial sequences are critical to the spatial and temporal reconstruction of the last British−Irish Ice sheet ( BIIS). Understanding glacial behaviour in the area of the Humber Gap is key as its blockage by ice created extensive proglacial lakes. This paper maps the glacial geomorphology of the Humber Gap region to establish for the first time the extent and thickness of the North Sea Lobe ( NSL) of the BIIS. Findings establish the westerly maximal limit of the NSL. Ten new luminescence ages from across the region show the initial Skipsea Till advance to the maximal limits occurred regionally at c. 21.6 ka (Stage 1) and retreated off-shore c. 18 ka (Stage 2). Punctuated retreat is evident in the south of the region whilst to the immediate north retreat was initially rapid before a series of near synchronous ice advances (including the Withernsea Till advance) occurred at c. 16.8 ka (Stage 3). Full withdrawal of BIIS ice occurred prior to c. 15 ka (Stage 4). Geomorphic mapping and stratigraphy confirms the existence of a proto Lake Humber prior to Stage 1, which persisted to Stage 3 expanding eastward as the NSL ice retreated. It appears that proglacial lakes formed wherever the NSL encountered low topography and reverse gradients during both phases of both advance and retreat. These lakes may in part help explain the dynamism of parts of the NSL, as they initiated ice draw down and associated streaming/surging. The above record of ice-dammed lakes provides an analogue for now off-shore parts of the BIIS where it advanced as a number of asynchronous lowland lobes. [ABSTRACT FROM AUTHOR]

During the last glaciation, most of the British Isles and the surrounding continental shelf were covered by the British-Irish Ice Sheet ( BIIS). An earlier compilation from the existing literature ( BRITICE version 1) assembled the relevant glacial geomorphological evidence into a freely available GIS geodatabase and map (Clark et al. 2004: Boreas 33, 359). New high-resolution digital elevation models, of the land and seabed, have become available casting the glacial landform record of the British Isles in a new light and highlighting the shortcomings of the V.1 BRITICE compilation. Here we present a wholesale revision of the evidence, onshore and offshore, to produce BRITICE version 2, which now also includes Ireland. All published geomorphological evidence pertinent to the behaviour of the ice sheet is included, up to the census date of December 2015. The revised GIS database contains over 170 000 geospatially referenced and attributed elements - an eightfold increase in information from the previous version. The compiled data include: drumlins, ribbed moraine, crag-and-tails, mega-scale glacial lineations, glacially streamlined bedrock (grooves, roches moutonnées, whalebacks), glacial erratics, eskers, meltwater channels (subglacial, lateral, proglacial and tunnel valleys), moraines, trimlines, cirques, trough-mouth fans and evidence defining ice-dammed lakes. The increased volume of features necessitates different map/database products with varying levels of data generalization, namely: (i) an unfiltered GIS database containing all mapping; (ii) a filtered GIS database, resolving data conflicts and with edits to improve geo-locational accuracy (available as GIS data and PDF maps); and (iii) a cartographically generalized map to provide an overview of the distribution and types of features at the ice-sheet scale that can be printed at A0 paper size at a 1:1 250 000 scale. All GIS data, the maps (as PDFs) and a bibliography of all published sources are available for download from: . [ABSTRACT FROM AUTHOR]

The discovery of Ice Ages is one of the most revolutionary advances made in the Earth sciences. In 1824 Danish-Norwegian geoscientist Jens Esmark published a paper stating that there was indisputable evidence that Norway and other parts of Europe had previously been covered by enormous glaciers carving out valleys and fjords, in a cold climate caused by changes in the eccentricity of Earth's orbit. Esmark and his travel companion Otto Tank arrived at this insight by analogous reasoning: enigmatic landscape features they observed close to sea level along the Norwegian coast strongly resembled features they observed in the front of a retreating glacier during a mountain traverse in the summer of 1823. Which glacier they observed up close has however remained a mystery, and thus an essential piece of information in the story of this discovery has been missing. Based on previously unknown archive sources, supplemented by field study, I here identify the key locality as the glacier Rauddalsbreen. This is the northernmost outlet glacier from Jostedalsbreen, the largest glacier in mainland Europe. Here the foreland exposed by glacier retreat since the Little Ice Age maximum around AD 1750 contains a rich collection of glacial deposits and erosional forms. The point of enlightenment is more precisely identified to be a specific moraine and its distal sandur at 61°53′26″N, 7°26′43″E. In memory of Esmark's travel companion who possibly was the first to realise the analogy, it is proposed to name this moraine Otto Tank's Moraine, a pendant to the already famous Esmark Moraine at Forsand by the sea. [ABSTRACT FROM AUTHOR]

This paper presents a detailed taphonomic study of the faunal assemblage from FLK West (Olduvai Gorge, Tanzania), a site with an Acheulean component that dates to 1.7 Ma. The faunal sample analysed here is distributed in different archaeological levels and is associated with a significant lithic accumulation including several large format tools and handaxes. The fauna indicates the proliferation of open environments similar to those found in other Bed II and late Bed I sites. Evidence of anthropogenic activity (e.g. defleshing activities and marrow consumption) has been identified in the form of cut and percussion marks. A photogrammetric and morphometric analysis suggests that these marks were produced with quartzite flakes and not with handaxes. Evidence of interaction with carnivores was also noted; tooth marks were observed on some bones. Such interaction indicates the existence of competition between humans and carnivores for the same ecological niche, and might lead us to reflect on the survival strategies of Lower Pleistocene hominins. [ABSTRACT FROM AUTHOR]

It is uncommon in the North Sea basin and northwestern Europe for the ice-marginal glacial successions of the Middle Pleistocene, Anglian (Elsterian) age to be well preserved and not overridden by subsequent glaciations. The existence of extensive and thick ( ˜20 m) Middle Pleistocene sand and gravel successions in East Anglia, England, provide a unique opportunity to reconstruct and understand the palaeoenvironmental conditions in the Anglian ice-marginal zone, and further across the North Sea basin. This paper uses data from 80 sections in two sand and gravel quarries in East Anglia to provide the first evidence concerning: (i) the character of the ice-marginal processes in the unique, transitional zone between the topographically constrained and unconstrained Anglian ice-sheet margin; (ii) the role of meltwater in the re-shaping of topographically driven preglacial drainage; and (iii) the position and the number of oscillations of the Anglian ice-sheet margin in the form of a sediment-landform assemblage. Moreover the current research adds to the discussion on the presence and extent of the proglacial lake in the North Sea Basin during the Anglian glaciation. The sand and gravel successions in the Anglian ice-marginal zone are primarily reworked proto-Thames sediments deposited by meltwater. At the beginning of the glaciation, the meltwater followed the preglacial (proto-Thames) river course. However, as the ice sheet advanced, it was re-routed, overwhelming and abandoning the old river course and depositing an extensive ice-marginal subaqueous fan. The succession includes evidence for at least two enhanced meltwater release events, as well as indications of glaciolacustrine sedimentation. The character of the described sedimentary settings is discussed in the wider context of the presence of the North Sea Lake. [ABSTRACT FROM AUTHOR]

Drought is a common natural disaster in arid Central Asia, and the severity and frequency of drought and other hydroclimatic events are critical to the region's ecology and its residents' livelihoods. In particular, water resource management requires reliable knowledge of climatic variability and annual and centennial drought patterns. In this paper, we establish a 587-year tree ring chronology using 215 Schrenk spruce ( Picea schrenkiana Fisch. et Mey) samples and reconstruct a spring Palmer Drought Severity Index ( PDSI) for the inner Tianshan Mountains spanning the 1645-2008 period. The reconstruction explains 40.3% of the variance during the sub-period for which we also have reliable observational data (1938-2005). Cross-validation during this common period also supports our reconstruction model. Spatial correlation analyses with gridded PDSI data show that our PDSI reconstruction reveals a strong regional drought signal for the central and western Tianshan Mountains. [ABSTRACT FROM AUTHOR]

Core preparation has been documented in Developed Oldowan assemblages dated between 1.5-1.3 Ma. However, its correct identification and significance is a matter of debate. In order to shed light on this issue, this paper attempts to reconstruct the flake production processes of the lithic assemblages currently recovered in SHK and BK at Olduvai Gorge (Tanzania). The methodological approach applied for the study of these two classical Developed Oldowan sites is based on the analysis and classification of flaking cores through detailed diacritical and technological descriptions, regardless of aprioristic morphological considerations. The flake production processes identified in both assemblages exhibit great technological homogeneity. The most remarkable difference between them is linked with divergences in flake size production. Core rotation and elongation of the perimeter of the flaked surface were the main technical actions implemented to manage core reduction, and seem to be related to reduction intensity. Core preparation, specifically striking platform preparation, was also applied, but to a minor extent, and was linked with a more effective management of blank reduction. It was not carried out through rigid technical and geometric schemes, and the products obtained were not predetermined. Nevertheless, its mere presence in Developed Oldowan sites is very suggestive, as it confirms a strong relationship between the Developed Oldowan and early Acheulean assemblages. [ABSTRACT FROM AUTHOR]

A thermokarst is a collapse feature resulting from the thawing of ice-rich permafrost or of massive ice of various origins. Little attention has been paid to the sedimentary fabric resulting from this type of collapse, except for glaciotectonic features. In western Europe, two palaeo-forms are commonly studied: lithalsas and ice-wedge casts. Collapsed pingos are much rarer. Very few papers have compiled present-day and fossil data. Here, field data collected from quarries in the eastern Paris Basin were analysed, providing useful records of thermokarst collapses in alluvial calcareous silts, sands, and gravels. These forms have a circular shape when viewed on satellite images. Permafrost is attested regionally by the recurrent occurrence of meter-sized pattern grounds at the surface of the chalk and of ice-wedge casts. Traces of segregation and reticulate ice are common. These features are primarily connected to a major interstadial, c. 150 ka BP, orbitally forced and commonly associated with a major glacial retreat. They occur both in drained and waterlogged situations, resulting in a specific pattern of deformation. They are controlled by the brittle and plastic behaviour of sediments and resemble passive glaciotectonism. Normal and reverse faults, with the offset decreasing downward, are common, and those with local shear are reported. Lithalsas, seasonal frost blisters, spring frost blisters and perhaps pingos seem to have formed. Most of these deformations correspond to thermokarst sinkholes bordered by gravitational collapse faults. The offset of these faults increases towards the surface, and the faults have been recurrently confused with neotectonism triggered by palaeo-earthquakes. However, there are no faults beneath the observed deformation features, and the region lacks recorded seismic activity over the last century. Our data may be helpful in interpreting similar structures elsewhere. [ABSTRACT FROM AUTHOR]

The relationships amongst modern pollen assemblages, vegetation, climate and human activity are the basis for reconstructing palaeoenvironmental changes using pollen records. It is important to determine these relationships at regional scales due to the development of vegetation under different climatic conditions and human activities. In this paper, we report on an analysis of modern pollen assemblages of 31 surface lake samples from 31 lakes (one sample per lake) on the southwestern Tibetan Plateau where the knowledge of modern pollen and their relationships with vegetation, climate and human activities is insufficient. The region includes five vegetation zones: sub-alpine shrub steppe, alpine steppe, alpine meadow and steppe ecotone, mountain desert and alpine desert. The lakes span a wide range of mean annual precipitation (50-500 mm) and mean annual temperature (−8 to 6 °C). Modern pollen assemblages from our samples mainly consist of herb taxa ( Artemisia, Cyperaceae, Poaceae, Chenopodiaceae, etc.) and some tree taxa ( Pinus, Fagaceae, Alnus, etc.). The results indicate that modern pollen assemblages are able to reflect the main vegetation distribution. Redundancy analysis for the main pollen types and environmental variables shows that precipitation is the leading factor that influences the pollen distribution in the study area with the first axis capturing 13.7% of the variance in the pollen data set. The Artemisia/Chenopodiaceae ratio is valid for separating the desert component (<2) from the steppe and other vegetation zones (>2) but is unable to distinguish moisture variations. The Artemisia/Cyperaceae ratio is able to identify meadows (<1) and steppes (>1) and can be used as a moisture index on the southwestern Tibetan Plateau. Our results show that an appropriate range is needed for a modern pollen data set in order to perform pollen-based quantitative climate reconstructions in one region. It is essential to perform modern studies before using pollen ratios to reconstruct palaeovegetation and palaeoclimate at a regional scale. [ABSTRACT FROM AUTHOR]

Blomvåg, on the western coast of Norway north of Bergen, is a classical site in Norwegian Quaternary science. Foreshore marine sediments, named the Blomvåg Beds and now dated to the Bølling-Allerød from 14.8 to 13.3 cal. ka BP, contain the richest Lateglacial bone fauna in Norway, numerous mollusc shells, driftwood, and flint that some archaeologists consider as the oldest traces of humans in Norway. The main theme of this paper is that the Blomvåg Beds are overlain by a compact diamicton, named the Ulvøy Diamicton, which was interpreted previously as a basal till deposited during a glacial re-advance into the ocean during the Older Dryas ( c. 14 cal. ka BP). Sediment sections of the Blomvåg Beds and the Ulvøy Diamicton were exposed in ditches in a cemetery that was constructed in 1941-42 and have subsequently not been accessible. A number of radiocarbon and cosmogenic 10Be exposure ages demonstrate that the diamicton is not likely to be a till because minimum deglaciation ages (14.8-14.5 cal. ka BP) from the vicinity pre-date the Ulvøy Diamicton. We now consider that sea ice and icebergs formed the Ulvøy Diamicton during the Younger Dryas. The Scandinavian Ice Sheet margin was located on the outermost coastal islands between at least c. 18.5 and 14.8 cal. ka BP; however, no ice-marginal deposits have been found offshore from this long period. The Older Dryas ice margin in this area was located slightly inside the Younger Dryas margin, whereas farther south it was located slightly beyond the Younger Dryas margin. [ABSTRACT FROM AUTHOR]

This paper reports an investigation into palaeoflooding along the upper reaches of the Hanjiang River valley, China. Based on the sedimentary evidence of the palaeohydrological regime, two bedsets of palaeoflood slackwater deposits (SWDs) were identified interbedded within the Holocene loess-soil sequence along the riverbanks of the Ankang east reach. Optical Stimulated Luminescence (OSL) dating and stratigraphical correlation with previously dated sites were used to reconstruct the chronology of the palaeoflood events. The results show that the palaeoflood events represented by SWD1 occurred between 13 000 and 12 400 a, coincident with the climatic transition from the Bølling-Allerød (BL+AL) stage to the Younger Dryas (YD) event. The palaeoflood events recorded by SWD2 were dated to 1000-800 a, corresponding to the later stages of the North Song Dynasty (AD 960-1127) and the subsequent South Song Dynasty (AD 1127-1279), which was a time of climatic decline according to historical documents. Palaeoflood discharges were estimated using the step-backwater method, and the peak discharges were estimated to be in the range 35 200-47 400 m3 s-1. These results are of significance to our understanding of the regional hydrological response to global climatic change, the utilization of water resources, hydraulic engineering, flood control and disaster reduction. [ABSTRACT FROM AUTHOR]

This paper focuses on pollen, spores, non-pollen palynomorphs (NPPs) and certain geochemical elements from the ombrotrophic blanket bog of Zalama (Basque-Cantabrian Mountains, northern Iberian Peninsula), with the support of a robust chronology based on 17 AMS 14C dates. The main results related to the last 8000 years show that, during the early middle Holocene, pines and deciduous forests were the most extensive tree formations. At the beginning of the succession, pines reach 44%, showing regional presence, whereas after 7600 cal. a BP, deciduous forests were particularly abundant. From c. 6500 cal. a BP the pollen diagram constructed from our samples shows the first anthropogenic evidence, linked with the new economic practices related to the Neolithic of the Basque-Cantabrian Mountains. From 3300 cal. a BP the expansion of Fagus sylvatica is particularly clear, and has since then become one of the dominant forest species in this region. We also discuss the Holocene evolution of other noteworthy plant communities in southwestern Europe, such as Taxus baccata, Juglans and shrublands. [ABSTRACT FROM AUTHOR]

In order to document changes in Holocene glacier extent and activity in NE Greenland (~73° N) we study marine sediment records that extend from the fjords ( PS2631 and PS2640), across the shelf ( PS2623 and PS2641), to the Greenland Sea ( JM07-174 GC). The primary bedrock geology of the source areas is the Caledonian sediment outcrop, including Devonian red beds, plus early Neoproterozoic gneisses and early Tertiary volcanics. We examine the variations in colour ( CIE*), grain size, and bulk mineralogy (from X-ray diffraction of the <2 mm sediment fraction). Fjord core PS2640 in Sofia Sund, with a marked red hue, is distinct in grain size, colour and mineralogy from the other fjord and shelf cores. Five distinct grain-size modes are distinguished of which only one is associated with a coarse ice-rafting signal - this mode is rare in the mid- and late Holocene. A sediment unmixing program (SedUnMix MC) is used to characterize down-core changes in sediment composition based on the upper late Holocene sediments from cores PS2640 (Sofia Sund), PS2631 (Kaiser Franz Joseph Fjord) and PS2623 (south of Shannon Is), and surface samples from the Kara Sea (as an indicator of transport from the Russian Arctic shelves). Major changes in mineral composition are noted in all cores with possible coeval shifts centred c. 2.5, 4.5 and 7.5 cal. ka BP (±0.5 ka) but are rarely linked with changes in the grain-size spectra. Coarse IRD (>2 mm) and IRD-grain-size spectra are rare in the last 9-10 cal. ka BP and, in contrast with areas farther south (~68° N), there is no distinct IRD signal at the onset of neoglaciation. Our paper demonstrates the importance of the quantitative analysis of sediment properties in clarifying source to sink changes in glacial marine environments. [ABSTRACT FROM AUTHOR]

This paper describes the results of a spatially dense anisotropy of magnetic susceptibility (AMS) till fabric study of a single drumlin in the Weedsport Drumlin Field, New York State, USA. AMS till fabrics provide a robust, quantitative and unbiased approach to assess subglacial till kinematics and infer ice-flow dynamics. The drumlin selected for this detailed investigation was systematically sampled at 18 locations to evaluate the patterns of ice flow and associated till kinematics within a drumlin and to test erosional vs. depositional models for its formation. AMS till fabric analysis yielded strong fabrics that increase in strength towards the drumlin crest, indicating that bed deformation occurred during till deposition and that deformation within the drumlin was greater than that in the interdrumlin low. Fabric orientations reveal drumlin convergent, divergent and parallel ice-flow paths that illustrate a complex interaction between ice flow and the drumlin form; fabric strength and shape reveal systematic differences in bed deformation between the interdrumlin and drumlin regions. These observations are inconsistent with purely erosional models of drumlin genesis; instead, these observations are more consistent with syndepositional streamlining of till transported, probably locally as a deforming bed, from the interdrumlin low towards the drumlin locality. [ABSTRACT FROM AUTHOR]