Tephra layers may be studied to understand the dynamics and sequence of past explosive volcanism. In Iceland, the distinctive Settlement Layer (AD ~877) underlies almost all archaeological evidence for the Norse Settlement and is preserved in soils across Iceland and as cryptotephra overseas. It comprises an olive‐green, tholeiitic basalt unit erupted from the Vatnaöldur crater row (within the Veiðivötn fissure swarm) and a white transitional alkali rhyolite unit from the Hrafntinnuhraun craters (within the Torfajökull complex). This paper describes a previously undocumented, dark‐grey tephra unit that we discovered in the Búland landholding (Skaftárhreppur). Electron probe micro‐analyses determined that this tephra unit is a bimodal transitional alkali basalt. Although it was deposited less than a year before the Vatnaöldur unit, it is unclear whether it also preceded the Hrafntinnuhraun unit. Nonetheless, we use the unit's thickness and composition to infer the likely origin to be Skyggnishlíðarvötn, a triplet of maar craters SW of the Torfajökull complex. The major‐/minor‐oxide composition of tephra collected from within the crater rim of the Skyggnishlíðarvötn maars (~45 km WNW of Búland) is indistinguishable from that of the unit we recorded near Búland. These findings demonstrate that volcanic unrest in the Veiðivötn fissure swarm is associated with explosive basaltic volcanism in the Torfajökull complex. The Skyggnishlíðarvötn phase may well have acted as a precursor to the impending Settlement eruption sequence.
The French Mediterranean region, like others in southern Europe, is thought to have hosted glacial refugia for temperate plants and animals. At its heart, the Rhône valley appears to have been a pathway for various organisms towards the northern areas. Two well‐dated postglacial molluscan successions were investigated. They allow for the reconstruction of postglacial palaeoenvironments and recolonization stages by temperate snails. Particularly responsive to habitat structure, the mollusc fauna invites reassessment of the extent of Lateglacial and Early Holocene steppe‐like formations which often appear underestimated. Only a few species with forest affinities appear since c . 10 500 cal. a BP. They are not very demanding in terms of tree cover and their abundance remains insignificant. For taphonomic reasons, the only truly forest snails are found here late, as relicts of a maximum known elsewhere between c . 8000 and 7400 cal. a BP. After the Lateglacial, steppe and wooded steppe snail communities are exclusive throughout the Early Holocene. They correspond with the juniper shrub‐steppe of anthracologists between c . 11 400 and 8900 cal. a BP. The cold‐stage species Xerocrassa geyeri coexists until c . 10 400 cal. a BP with newly recruited xerothermic snails. The return of the endemic Candidula rugosiuscula , as early as 13 100 cal. a BP, suggests the existence of local refugia during the LGM and the preceding glacial stages. Backeljaia gigaxii , absent from the Pleistocene before the Late Glacial Interstadial (LGI), could be an immigrant. The existence of local glacial refugia for open‐ground Mediterranean snails remains a priority question. The role of local refugia for forest snails only becomes effective after the 9.3 ka event due to aridity. That of classical forest macrorefugia is not apparent. In the future, we will be able to refer to these stratigraphic sequences and their malacological content to correlate the scattered and incomplete successions that are most frequent in the Lateglacial and Early Holocene regional record.
The AlpIce‐1 database is the first compilation of published geomorphological and geochronological markers constraining build‐up, culmination and decay of glaciers from the Last Glacial Maximum through the Holocene across the entire European Alps. AlpIce‐1 integrates more than 4200 surface‐exposure and radiocarbon ages, homogenized, quality controlled and evaluated for their palaeoglaciological context, compiled from 268 peer‐reviewed publications and over 1300 sites across the European Alps. The database includes ages originally obtained from a wide range of landforms and deposits including moraine ridges, lakes, mires, sediment outcrops, ice cores, bedrock surfaces, caves and archaeological sites. It documents chronological constraints on more than 1400 palaeoglacial events, including past ice‐margin stabilization, ice (re‐)advance, ice retreat, ice‐free or ice‐cover conditions. A GIS catalogue of more than 260 dated landforms (e.g. moraines, rock glaciers, landslide deposits) complements the database. AlpIce‐1 is designed as an open‐access resource supporting both field and modelling studies across the Alps and is intended for all communities interested in the late Quaternary. In light of emerging next‐generation numerical ice models, AlpIce‐1 offers an extensive and robust empirical basis for evaluating future (palaeo)glacier simulations.
Owing to its location in the semi‐arid region of northern Central Asia, Mongolia is highly sensitive to climate change and therefore provides an excellent setting for palaeoenvironmental research. Proxy data from different sediment types are crucial for interpreting past climate changes and landscape evolution, while burial ages provide chronological frameworks for reconstructing specific periods. However, since deposits may originate from multi‐genetic process chains and sediment cascades, determining the timing of their last transportation and deposition needs a clear geomorphological analysis of the geoarchives. Optically stimulated luminescence (OSL) dating is a well‐established method in determining burial ages. However, OSL dating of sediments in Mongolia is challenging. The quartz OSL signal of sediments in Mongolia is often dim and exhibits feldspar contamination. As a result, previous studies mostly used K‐feldspar (KF) post‐IR infrared stimulated luminescence (pIRIR) signals for luminescence dating. However, KF pIRIR signals bleach much slower than quartz OSL signals, and insufficient bleaching of pIRIR signals prior to deposition might result in burial age overestimation, especially for water‐lain sediments where exposure to sunlight is often limited. Single‐grain (SG) dating of KF could be a useful tool in this case, as it can derive reliable burial ages for partially bleached samples by applying a minimum age model. Hitherto, the reliability of KF SG dating has not been sufficiently studied on Mongolian sediments. In this study, we performed both KF SG dating and multi‐grain dating with the pIRIR 150 signal (pIRIR signal at 150 °C) on 30 sediment samples collected from 17 profiles across Mongolia, together with 14 C dating of 12 samples of organic sediment and plant material. KF SG dating results show that only the five samples of primary aeolian sediment were well bleached prior to deposition, while all of the 25 samples of remobilized, transported and redeposited sediment (e.g. by fluvial, alluvial and colluvial processes) were partially bleached during the final transport process, thus showing positively skewed distributions of SG equivalent doses. The KF ages obtained with multi‐grain aliquots significantly overestimated the true burial ages and often showed age reversals. KF SG ages obtained by applying a minimum age model were consistent with radiocarbon ages and followed the stratigraphic order. Our study demonstrates that KF SG dating is the most suitable luminescence dating method for re‐deposited aeolian sediments in Mongolia.
This study presents a multiproxy reconstruction of palaeoenvironment under variable climatic conditions from the retreat of the Saalian ice sheet (MIS 6a) to the Late Weichselian (MIS 2), based on an analysis of mineral and biogenic sediments from a palaeolake at the J & oacute;zef & oacute;w site (central Poland). The diversity and disturbances of sediments studied at J & oacute;zef & oacute;w highlight the general need to combine multiple research techniques for a comprehensive reconstruction; however, they also demonstrate the limitations of methods used in such analyses. Lithological, geochemical and palaeobotanical analyses of a 7.5 m sediment succession from the CO-1 core and several outcrops completed using previous OSL dating reveal that lacustrine accumulation started in the active permafrost layer. Pollen, macrofossils and geochemical records indicate that, during the lateglacial of the Saalian (MIS 6a), the lake was initially surrounded by steppe-tundra plant communities, then supplemented by pioneering birch and pine patches, followed by a deterioration in conditions expressed as increased amounts of open-steppe vegetation and intensified erosion processes. This record indicates traces of climate oscillations in the Late Saalian. At the onset of the Eemian interglacial (MIS 5e), the lake became shallow and transitioned into a peat bog during a mesocratic phase, remaining so until the middle of the oligocratic phase. Sediment accumulation in the basin continued into the Early Weichselian (MIS 5d-a), ceasing around 58 ka, confirming the typical development succession of Eemian-Early Weichselian lakes in the Polish lowlands. No deposits or direct traces of erosion from MIS 4 and MIS 3 were identified, which reflects a widespread hiatus across central-eastern Europe. OSL dates can be rejuvenated by a highly dynamic periglacial environment and therefore do not correlate precisely with palaeobotanical data. Thermal contraction fissures formed due to intense permafrost aggradation (MIS 2, Leszno phase, 25-21 ka), supporting a previous hypothesis that a frost mound existed at J & oacute;zef & oacute;w. The Weichselian is recorded in mineral sediments deposited as a result of intensive mass-flow processes and sedimentation from suspension in a shallow lake during gradual degradation of permafrost (after the Leszno phase) and in aeolian sediments from the final stage of the Late Weichselian (Oldest/Younger Dryas). The J & oacute;zef & oacute;w case study provides a detailed record of environmental and climate changes and confirms the main traces of Late Pleistocene landscape morphogenesis in central-eastern Europe.
Numerous studies have shown that during the Quaternary there were substantial fluctuations in sea level in response to glacial-interglacial climate variability, reaching lowstand positions up to 134 m below the present sea level (b.s.l.). These fluctuations have had a strong influence on the morphology of shallow shelf seas, which preserve evidence of former terrestrial and coastal landscapes that are now submerged. Geomorphic analyses of submerged coastal landforms, such as marine terraces and clinothems, can thus provide valuable information regarding palaeoshoreline positions and insights into past sea levels. In this study, using high-resolution acoustic methods, we investigated the & Zcaron;irje Archipelago located along the central part of the karstified eastern Adriatic coast to detect the distribution and characteristics of submerged palaeoshorelines. The acquired data revealed a series of marine terraces at depths between 44.5 and 207.9 m b.s.l. Comparisons with available sea-level curves show that these terraces formed during periods of sea-level stillstands or decelerated rates of sea-level rise, extending back to at least Marine Isotope Stage 10. In addition, progradational shelf-edge delta clinoforms with rollover points at depths ranging from 127 to 131 m b.s.l. indicate the position of the shoreline during the Last Glacial Maximum (LGM). These features, observed on the slope towards the Mid-Adriatic Deep, are interpreted as a lowstand wedge of the Late Pleistocene Krka River. By integrating information on erosional marine terraces and depositional clinothems, we propose new constraints on the evolution of Quaternary shorelines and variability in regional relative sea levels. Moreover, for the first time, we tentatively identify the position of the palaeoshoreline along the eastern Adriatic during the LGM. The surveyed area proved to be a natural laboratory for studying shelf-edge environments adjacent to sediment-starved karstified coasts.
Loess-palaeosol sequences (LPS) represent one of the most important continental archives of late Quaternary environmental change in Europe. Establishing reliable chronologies is essential for reconstructing dust dynamics and for correlating regional loess stratigraphies. In this study, we present the first systematically derived mass accumulation rate (MAR) dataset for six key Polish LPS, based on high-resolution Optically Stimulated Luminescence dating of the 45-63 mu m quartz fraction. Bayesian age-depth models were constructed using the Bacon software. The results demonstrate pronounced temporal and spatial variability in loess accumulation across southern Poland. All profiles show maximum MARs during MIS 2, with exceptionally high values exceeding 1000 g m-2 a-1 at Trzebnica, Tyszowce and Strzy & zdot;& oacute;w sites. In contrast, Zapr & eogon;& zdot;yn site exhibits lower MARs with only localized peaks. The results highlight the utility of luminescence-derived MARs for investigating regional aeolian dynamics, while also emphasizing the methodological limitations imposed by chronological uncertainties and sampling resolution.
Glacially overdeepened valleys in the northern Alpine Foreland preserve Middle to Late Pleistocene sedimentary sequences that may serve as valuable archives for reconstructing past environmental changes in response to shifts in climate. This study presents a multidisciplinary analysis of two sediment cores from the overdeepened Wehntal Valley at Niederweningen in northern Switzerland, integrating sedimentological, palaeobotanical (pollen, plant macroremains) and malacological data as well as luminescence dating. The basal sediments of the cores consist of lacustrine silts deposited under cold climatic conditions, associated with a treeless landscape and later with pioneer birch woodland. Previous studies have reliably attributed these deposits to the Penultimate Glaciation, that is the equivalent of Marine Isotope Stage (MIS) 6. Overlying this unit, carbonate-rich silts containing a rich suite of biological remains were identified for the first time in the Wehntal Valley. These deposits suggest sedimentation in a marshy wetland bordered by mature deciduous-coniferous forest, which corresponds to the early-middle Eemian (MIS 5e). Above this, silty and peaty sediments indicate alternating lacustrine and marshy conditions under a variable climate, with a predominantly coniferous woodland, during the Early W & uuml;rmian (MIS 5d-5a). Subsequent cooling, corresponding to MIS 4, led to a return to lacustrine conditions and a more open landscape. This stratigraphical and palaeoenvironmental framework aligns with previous studies in the Niederweningen area, confirming that the 'Lower Peat' unit is of middle to late Eemian age, while the 'Upper Peat', which contains mammoth remains, dates to MIS 3. During late MIS 3 or early MIS 2, the valley-bottom lake disappeared and was replaced by a modest stream network with slope deposits from the sides of the Wehntal Valley. Although this chronostratigraphical interpretation is strongly supported by the biological proxies, luminescence dating results are in partial contradiction. The luminescence ages from one core are in fairly good agreement with the proposed sequence, while those from the other suggest that most of the sequence corresponds to the Early W & uuml;rmian (MIS 5d-5a) after c. 100 ka. Reconstructing this complex sequence has been complicated by significant erosive events linked to fluctuations in palaeolake levels that led to important sedimentary hiatuses.
The Ural Mountains form a major physiographic boundary between the East European Plain and West Siberia, both repeatedly glaciated during the Pleistocene by the Barents-Kara ice sheet. Although the present-day topography reflects significant glacial modification, the extent, chronology and interaction of mountain glaciers with the Barents-Kara ice sheet remain poorly constrained. Correlation of glacial and interglacial deposits across the range is hindered by incomplete sedimentary records, contrasting palaeoclimatic conditions and limited chronological control, which collectively obscure regional glacial reconstructions. This study presents an extensive mapping exercise of hundreds of moraines in the northern Urals. These landforms are then used to reconstruct palaeoglacier equilibrium line altitudes (ELAs) to assess glacier distribution and synchroneity of moraine formation. ELA trends along the Urals are analysed to evaluate whether, and where, montane ice caps developed during the last major glaciation. Furthermore, palaeo-ELA data are used to link former ice margins to dated moraines in the Polar Urals, providing new insights into the spatial and temporal dynamics of montane glaciations south of the Arctic Circle. The findings indicate that the E-W asymmetry in the hypsometry of the Urals exerted the primary control on the development of the piedmont glaciers on the lowlands. Furthermore, glacier reconstructions combined with geomorphological evidence favour the existence of extensive montane ice caps over the Urals with moisture sourced from extensive ice-dammed lakes located on both sides of the mountain range.
Palynological records are central to the biostratigraphic subdivision of the Late Pleistocene in central Europe. Yet many interglacial and interstadial phases-such as the Eemian, Br & ouml;rup and Odderade-remain only poorly constrained in time due to limited numerical dating. This lack of robust chronologies hampers efforts to assess the synchronicity of climatic and ecological transitions across regions and to contextualise human occupations during this period. Here, we present a 21-m-long, high-resolution lacustrine sediment succession from northern Germany that spans the Saalian late glacial (late Marine Isotope Stage-MIS 6) to the Weichselian pleniglacial (MIS 4 to MIS 2). Using a multi-proxy approach combining palynology (partially automated), sedimentology, geochemistry, magnetic susceptibility and microfossil-based reconstructions, we develop a detailed palaeoenvironmental reconstruction for this period. This is supported by 25 luminescence samples incorporated into a previously published Bayesian age-depth model, thus offering one of the most continuous and well-resolved chronologies for this interval in the region. According to our findings, the Saalian late glacial pollen zones B and C occurred between similar to 133-132 ka and similar to 132-129 ka, respectively. The Eemian interglacial lasted similar to 21 500 years (similar to 128.8-107.3 ka), significantly longer than previously estimated at the key reference site of Bispingen (similar to 15 000 years). The Br & ouml;rup and Odderade interstadials are constrained to similar to 100-88.2 and similar to 77-72 ka, while three newly identified, short-lived interstadials (WP Li Os I-III) occurred during MIS 4 and MIS 2 (similar to 69, 61 and 25 ka). These findings reveal hydrological and ecological responses that were partly asynchronous with both North Atlantic climate signals and biostratigraphic zonation, suggesting regional lags in vegetation change and/or uncertainties in the age-depth model. By providing a high-resolution, and independently dated palaeoenvironmental framework, this study improves the chronological constraints of central European pollen zones and thus offers a new basis for archaeological interpretations of Neanderthal activity. Our results call for re-evaluation of assumed synchrony in climate-ecosystem transitions across Europe during the last interglacial/glacial cycle and underscore the need for further high-resolution, numerically anchored records across the region.
The Holocene relative sea-level (RSL) history of Norway's largest island, Hinnoya, has been investigated in detail, using sediment records from 25 isolation basins. The sediments were analysed for macrofossil and phytoplankton content, which served as the basis for identifying marine-lacustrine transitions, that is isolation contacts. Terrestrial plant remains from the transitions between depositional environments were radiocarbon dated to obtain ages of palaeo-sea levels corresponding to the basin threshold elevations. We also mapped morphological traces of the 7-8 ka, diachronous "Tapes shoreline", which becomes younger from southeast to northwest across the field area. The regional Tapes shoreline isobase direction is 45 degrees northeast, and the shoreline tilt is 0.37 m km(-1). RSL curves have been constructed for two sites located 12.5 km apart across the isobase direction: Oksnes on southern Hinnoya, and Tjeldsundet east of the island. Postglacial land emergence at rates of similar to 20 mm a(-1) was interrupted by the Tapes transgression, which started around 9.3-9.0 ka and lasted until a highstand was reached at 8.0-7.5 ka. RSL has since fallen, at a mean rate of similar to 3 mm a(-1). A shoreline diagram for a 25 km long transect across Hinnoya shows details of the changing shoreline geometry through time, and extrapolated shorelines provide insights into the regional extent and magnitude of the Tapes transgression. Five of the basin records hold traces of the similar to 8200-year-old Storegga tsunami, which had a vertical run-up of at least 4 m on southern Hinnoya and propagated more than 25 km northward, into the narrow marine strait of Tjeldsundet. The results are compared with recent modelling of the postglacial RSL history for the same region, demonstrating that the modelling fails to capture the details and variability of RSL change, at a relevant scale for environmental reconstruction and chronological use. The modelled RSL curves will often be misleading on a local scale and should not be used for geological or archaeological interpretations.
Our knowledge of the Early Upper Palaeolithic occupation in northern central Europe is very limited, and recent research at the open-air site of Friedrichsdorf-Seulberg in Hesse, Germany, provides important new information on the Aurignacian. The site is rather small (26.5 m2) and spatial analysis identified a central hearth with two associated activity zones, including a probable refuse pit. Multidisciplinary analyses of lithic artefacts, faunal remains, charcoal and site stratigraphy suggest a single short-term, seasonal occupation by a small hunter-gatherer group. The lithic assemblage is dominated by carinated and nosed scrapers and microblades, indicative of on-site tool maintenance related to composite hunting weapons. The faunal assemblage is primarily composed of reindeer, and the presence of cut marks, fresh bone fractures and burnt bones suggests that butchery and marrow processing took place at the site. New radiocarbon (AMS) dates of 38 810-35 150 cal. a BP, which are consistent with the luminescence ages, place the site's occupation within the late Greenland Interstadial 8 or Greenland Stadial 8. Charcoal analysis reveals Pinus as the dominant wood taxon used as fuel for the hearth and supports a steppe-tundra environment. The presence of raw materials such as Baltic flint and Jurassic chert transported over a distance of at least 170 km highlights extensive mobility networks in northern central Europe.
Ice sheets and glaciers globally are losing mass at increasing rates, with the strongest changes occurring at tidewater glaciers. These are rapidly retreating and often transitioning to land-terminating with implications for sea level change and ecosystem functioning. However, reconstructions of past tidewater glacier dynamics are currently limited to short time scales (i.e. decades), which affects the accuracy of future predictions. Given the strong response of benthic marine biodiversity to tidewater glacier-induced environmental gradients, small fossilizing organisms such as foraminifera may prove to be a reliable ecological proxy for glacier termini positions on longer time scales. Here, we test living benthic foraminiferal taxonomic and functional diversity along a decreasing gradient of environmental stress off the Kronebreen tidewater glacier front in Kongsfjorden, Svalbard. Additionally, we test four traditional size fractions used for foraminiferal analysis (i.e. >63, >100, >125 and >150 mu m) to statistically define the best compromise providing reliable information with minimal analytical time. Both taxonomic and functional diversity increased with increasing distance from the glacier front. The observed diversity patterns were consistent across size fractions, although some were not detected by the largest size fraction (>150 mu m). The size fraction >125 mu m seems to represent the best compromise to obtain reliable ecological information. We hypothesize that reduced glacier-induced disturbance away from the glacier front increases the availability of ecological niches, which in turn allows the establishment of functionally diverse species. Conversely, only few opportunistic species with reduced functional diversity were associated with the highly unstable environment near the glacier front. The progressive benthic foraminiferal diversity loss observed towards the glacier front is a potential ecological proxy for tidewater glacier dynamics in historical and palaeo-reconstructions. Its effectiveness and robustness to seasonal variability and taphonomic processes should be tested on historical records.
Rapid thaw of the Earth's cryosphere in response to anthropogenic warming highlights the need to identify and understand the contrasting signatures of past ice‐sheet stability and collapse. The Kvarken archipelago, western Finland, at the centre of the former Fennoscandian Ice Sheet (FIS), has been designated a UNESCO World Heritage site in recognition of the exceptional preservation of glacial landforms exposed by rapid (10 mm a−1) postglacial isostatic uplift. Detailed mapping of hard and soft glacial bedforms allows reconstruction of ice sheet dynamics over the last glacial cycle. Striation orientation measurements (n ~ 1100) were made at 700 sites on Precambrian gneiss and granite bedrock surfaces around the present shorelines. The striation data are classified into relative age categories and broader striation arrays to identify ice‐flow paths and then integrated with other directional indicators from overlying glacial sediments and landforms. The full data set reveals a sequence of six ice‐flow stages, which are then placed in a revised event and chronostratigraphic model for the wider Ostrobothnia region. After a major glacial erosion phase in Kvarken in late MIS 6, ice sheets returned in MIS 4 and MIS 3. During brief sliding phases, till sheets were deformed and eroded, but cross‐striations indicate that bedrock erosion was locally weak (<0.5 m) until after the last glacial maximum. At 11.6 ka, summer temperatures in Fennoscandia rose abruptly by 3–6 °C, and large volumes of meltwater reached the glacier bed. At 10.7–10.5 ka, a fast ice‐flow phase, the Gävle Oscillation, developed in the Bothnian basin. A <400‐year pulse of intense subglacial activity began in Kvarken, with abrupt and often pronounced switching of flow, production of new striation arrays, widespread erosion of till and bedrock and the formation of new soft bedforms. Existing till sheets were extensively glaciotectonically deformed into a young set of ribbed moraines. Local ice‐flow events led to the development of low‐relief megaflutings, drumlins and flutings. Bedrock was hydraulically damaged by large discharges of pressurized meltwater flowing in subglacial meltwater corridors, generating dense concentrations of large boulders. The ice margin retreated at 200–700, even 1000 m a−1, with deposition of De Geer moraines in water depths of 220 m, before final deglaciation at 10.4–10.3 ka. Our Kvarken case study indicates that after slow erosion beneath stable ice sheet centres in MIS 4 and MIS 3/2, abrupt Early Holocene warming triggered ice sheet collapse and brought profound changes at the ice sheet bed over centennial time scales.
The ongoing global sea-level rise urges us to better understand the dynamics of coastal processes for predicting future changes. Sedimentary deposits reflect past coastal environments but require precise chronological data to place evidence into a temporal context. While radiocarbon dating is widely employed, it is associated with several methodological challenges and frequently there is an absence of datable material in coastal deposits. Luminescence dating provides an important advantage over radiocarbon by directly determining the time of sediment deposition. However, this method is affected by problematic issues such as partial bleaching, bioturbation and dose rate assessment, which can lead to inaccurate age determinations. As a case study demonstrating good scientific practice in luminescence dating, we investigated deposits from the Chanthaburi Plain, Thailand, for reconstructing past coastal dynamics. Luminescence screening is used to identify potential signal disturbances and select appropriate sample positions in the drill cores. Luminescence dating was performed on 13 samples accompanied by detailed analysis regarding dose rate with a focus on water content and radioactive disequilibrium. The dated samples indicate depositional ages ranging between 7.2 and 4.6 ka. Comparison with radiocarbon ages (18 samples) reveals that plant material often represents modern roots and that molluscs tend to systematically underestimate the sedimentation age, likely due to partial recrystallisation. Our data suggest at c. 6.5 ka, a location of the coastline similar to 8.1 km inland from the present position. At around 4.6 ka, the coastline was about 7.2 km from the present shore. Together with previously published data, this indicates a sea-level regression from the Middle Holocene highstand towards the Late Holocene.
Effective and sustainable land use, conservation, and the use of geological resources (incl. raw materials, aggregates and groundwater) require a clear classification system of sedimentary units, with well-defined vocabulary and unified mapping practices. To ensure harmonization of the GTK's (Geological Survey of Finland) map database of Finnish Quaternary surficial features, classification criteria for glaciofluvial landforms have been updated. The work is based on earlier geological field mapping of surficial Quaternary deposits as well as previous and ongoing LiDAR DEM-based mapping of glaciofluvial landforms in Finland. In this paper, we present the updated classification and terminology, discuss the defining criteria of glaciofluvial map unit types and show their representative examples. Inherent challenges and limitations of this remote sensing-based mapping approach are also discussed.
The Megalopolis Basin is located in the central Peloponnese (Greece), a region that is situated along one of the primary Pleistocene biogeographical corridors for intracontinental hominin migration. The basin comprises several hundred metres of Plio-Pleistocene sediments alternating between clastics and lignites. Of these sediments, a 6 m thick succession deposited during the cold Marine Isotope Stage (MIS) 12 (similar to 480-420 ka) was intensely studied after the discovery of evidence for hominin presence in these strata at the Marathousa 1 Lower Palaeolithic site. The local environmental conditions prior to and after this period, however, are still unknown. Here, we present the results of sedimentological analyses of two >100 m long drill cores (MAR18-1A and MAR18-2A) and two outcrops (MAR19-2AP, Choremi-6) in order to provide palaeoenvironmental constraints on the Megalopolis Basin between similar to 780 and 340 ka. Our age control is based on palaeomagnetic analysis conducted on the drill core MAR18-1A and the Choremi-6 outcrop, as well as correlations to formerly studied cores and outcrops. The geochemical and lithological proxies and their statistical processing reveal that the basin was characterized by a periodically changing environment influenced by a deltaic river during dry and/or cold intervals (clastic layer deposition) and lacustrine environments that were fringed by lush, limno-telmatic vegetation during humid and/or warm periods (lignite seam formation). Our results provide high-resolution insights into climatic changes in the immediate surrounding of the archaeological sites in the Megalopolis Basin during the Early to Middle Pleistocene, disclosing further investigation opportunities on palaeoclimate, palaeoenvironment and human activity in the region.
Glacial erosion during the Last Glacial Maximum (LGM) has removed much evidence of earlier glaciations and interglacials in the European Alps. At Gröbminger Mitterberg (GM), beneath a blanket of LGM till, a distinctive sediment archive preserves deposits predating the LGM. GM is a flat‐topped hill in the Enns Valley, Styria (Austria), rising ∼200 m above the valley floor between Mesozoic carbonates (north) and crystalline basement units (south). Crystalline bedrock (phyllite, greenschist) is overlain by subglacial, deltaic, fluvial and glaciolacustrine sediments, with soft‐sediment deformation (clastic dykes) and capped by LGM till. Outcrop, borehole, and electrical resistivity tomography data reveal a bedrock surface incised by a channel. The Middle–Late Pleistocene succession begins with the Lower Till, attributed to the Rissian glaciation (MIS 6), which reshaped a fluvially moulded bedrock surface by intense subglacial erosion, including meltwater activity. Above lies the Mitterberg Unit. The up to 100 m thick Dorf (Allo‐)Member comprises delta foresets with slumps, rare dropstones and dead‐ice contact structures, correlated to Termination II (MIS 6) by luminescence ages of 140±20 ka. The 10 m thick Zirting (Allo‐)Member records fluvial deposition. The upper Frankenbichl (Allo‐)Member consists mainly of interbedded lacustrine and deltaic sediments, showing overall aggradation. Luminescence ages of 47±8 ka suggest a lake formed in MIS 3 by a prograding alluvial fan under cold, ice‐free conditions. The lacustrine succession records alternating delta progradation and dam‐burst‐caused regression. Uppermost Frankenbichl glaciolacustrine deposits reflect glacier‐proximal settings marking the onset of Würmian Pleniglacial (MIS2) ice build‐up. The LGM till unconformably overlies the Mitterberg Unit and forms drumlins. Overall, these reconstructions link climate change, erosion and sedimentation in the Enns Valley, providing a framework for modelling Alpine glaciations and intervening greenhouse phases.
This study investigates the species composition and distribution of gallinaceous birds (Galliformes) in the south of eastern Europe, specifically within the territory of present‐day Ukraine, during the Late Pleistocene and Holocene. The research is based on the comprehensive revision of skeletal remains found at archaeological sites. The findings reveal that seven galliform species were present in the region during these periods: hazel grouse, willow ptarmigan, rock ptarmigan, capercaillie, black grouse, grey partridge and common quail. The study highlights the crucial role of the Crimean Mountains as a refugium during the last glaciation, where the greatest diversity of gallinaceous birds was observed. The research also addresses the changes in the distribution and abundance of these birds over time, noting the loss of some species and the appearance of others. The findings underscore the importance of understanding past environmental changes and their impact on bird populations, which can inform current conservation efforts. The study concludes that while some species have shown high ecological plasticity and adaptability, others have experienced significant range contractions requiring targeted conservation measures.
