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This paper presents an overview of the results obtained by collaborative use of integrative multidisciplinary investigation of a highly unique geological section discovered in the south-eastern part of the Gulf of Finland. The main aim of this study is to identify the Late Pleistocene palaeoenvironmental and palaeoclimatic changes in the study area during one of the most controversial periods in the Late Pleistocene history, which is the MIS 5. Our approach to achieving the goal is based on the investigation of feldspar-based infrared optically stimulated luminescence (IR-OSL) dated records of pollen-induced palaeoclimate and palaeoenvironmental proxies. Palynological analysis and IR-OSL dates of 29 samples for the first time produced a detailed, characterised and dated sequence of palynological zones M6 to M8 ranging from ca. 94 ka to ca. 70 ka and made it possible to determine the chronological sequence of climate changes in this interval. Representative pollen spectra from 69 samples provided convincing evidence of a warm interval of interglacial rank at least during the latter half of MIS 5. The data obtained in the present study from well-preserved deposits of the second half of MIS 5 provided a novel insight into the palaenvironmental conditions during this period. These results seem to contradict the widely held view according to which the last interglacial stage with the climate conditions similar or warmer than today corresponds to only a small part of marine isotope stage (MIS) 5 of the deep-sea stratigraphy, i.e. MISs 5e lasting ca. 11 ka, and the period from 100 ka to 80 ka is attributed to an Early Weichselian glaciation, which in Northern Eurasia reached its maximum at about 90 ka. However, the findings obtained during the present study are also convincingly confirmed by those of our previous long-term investigations of warm climate-related shell-bearing deposits of various origins from Northern Eurasia including climatically highly sensitive Eurasian Arctic palaeo-shelf area. These results indicated that the overwhelming majority of the warm climate-related dates (ca. 82%) is also concentrated in the latter half of MIS 5 in the time range between 110 ka and 70 ka.

The Lithuanian onshore section of the south-eastern Baltic Sea region, or the so-called Lithuanian Maritime Region (LMR) – a belt several tens of kilometres wide along the Baltic Sea coast – is characterised by a complicated Quaternary structure and many of unsolved problems related to stratigraphy and palaeogeography. The inter-till lacustrine sediments widespread in the middle part of the Pleistocene thickness play a key role in solving the mentioned problems. The primary inter-till sediments were attributed, as a single lithostratigraphic unit, to the late Saalian Glaciation (MIS 6, Pamarys Sub-Formation; according to the Lithuanian Quaternary Stratigraphic Scheme). Subsequent detailed investigations show that the investigated inter-till succession represents a more complicated sediment complex formed over a wide time interval from the Saalian ice sheet decay at the very end of MIS 6 to the beginning of severe climate cooling during MIS 4. This standpoint is confirmed by the results of a few series of OSL and IR-OSL datings of inter-till sediments, as well as by data of pollen and diatom analysis. The more detailed stratigraphic subdivision of the inter-till sedimentary complex offers a new significant insight into the regional stratigraphic scheme of the Quaternary. As a result of the mentioned investigations, a new original reconstruction of the palaeogeographic situation in the LMR during the MIS 6 – MIS 3 time span was carried out. The lowermost part of the investigated inter-till sediments, attributed to MIS 6, could be correlated with the third MIS 6 warming in Northern Eurasia about 155 ka ago. The reconstruction of the palaeoenvironmental changes starting from MIS 6 and lasting to MIS 3 shows that the Eemian Sea MIS 5e in age was absent in the LMR, while part of the south-eastern Baltic Sea region was covered by a continental ice sheet during MIS 4 and, possibly, the very beginning of MIS 3.

—Terraces at four hypsometric levels were studied in the Vuoksa River basin (northern part of the Karelian Isthmus, NW Russia). New data on nine sections of late Quaternary–Holocene sediments have been obtained. Their age has been determined (for the first time for surface deposits in the studied region) in the interval from 90 to 2 ka. The terrace sediments are disturbed by deformations (faults, folds, and liquefaction) caused by six strong earthquakes in that period. The relationships among the terrace levels, ages, stratigraphy, and structures of loose sediments point to their formation under the impact of differentiated tectonic motions triggered by the activation of the ancient “Vuoksa” fault zone in the late Neopleistocene and Holocene.

This study provides a new stratigraphic and palaeogeographic scheme for the time span between Marine Isotope Stages (MISs) 8 and 6. Based on detailed sedimentological and palynological studies, the...

Analysing the genesis of Quaternary sediments is important for understanding the glaciation history and development of marine sediments in the northern part of Western Siberia. The problem is relevant since there is no consistent concept of the Quaternary sediment genesis in the north of Western Siberia. The formation of sediments is associated with marine, glacial and interglacial sedimentation conditions. The research objective is to identify the persistent features characterising the conditions of sedimentation and relief formation using the Nadym River basin as an example. The best method for studying this problem is a comprehensive analysis of the lithological, chronostratigraphic, petrographic and geomorphological studies of the Quaternary sediment upper strata. This study provides data from the analysis of the basic characteristics of quartz grains at the site. The rounding and morphology of the quartz grains provide evidence of possible glacial processing of some of the site strata. A petrographic study of selected boulder samples was performed. Some of them, by the shape and presence of striation, can be attributed to ice basins. The first use of a detailed digital elevation model applied to the study area made it possible to identify specific relief forms that could very likely be created during glaciations. Based on the analysis, we propose to consider the vast lake alluvial plains in the Nadym River basin as periglacial regions. This idea lays the lithological framework for understanding the reasons for the formation of the modern landscape structure. The materials and descriptions provided are of interest to researchers of Quaternary sediments, topography, vegetation and soil cover, particularly researchers engaged in revising the history of the natural environment development in the north of Western Siberia.

Long-term investigations devoted mostly to the Eurasian Arctic sedimentary deposits have provided dated climatic sequence within the Late Pleistocene period. Most of the dates (ca. 315) were obtained by electron spin resonance (ESR) method on marine mollusc remains taken directly from transgressive marine sedimentary deposits. Here, it is shown that the climatic signature revealed in the studied sedimentary sequences can be compared by proxy- and chronologic correlation with the climatic signals recorded in different parts of the continent from deposits of marine, freshwater, and terrestrial origin. The resulting climate-chronostratigraphic record allow the last interglacial to be placed approximately between 145–140 ka and 70 ka with concentration of overwhelming majority of the warm climate-related dates (ca. 82%) in the second half of Marine Isotope Stage (MIS) 5 in the time range between 110 and 70 ka. This evidence coincides with integrative multidisciplinary results derived from the south-eastern coast of the Gulf of Finland. They show unambiguously that the second half of the MIS 5 sequence, at least between ca. 94 ka and 71 ka, reflects the fully interglacial character of the studied deposits. The climate-chronostratigraphic record within MIS 3 displays a sequence of three successive palaeoenvironmental events (59.0–52.0 ka, 47.5–40.0 ka and 32.4–24.8 ka), which are interpreted as the consequence of large-scale climate amelioration during which marine sedimentation occurred on palaeo-shelves what is now dry land. The consistency of the parallel comparative dating results obtained in this study by different methods, both the numerical and relative, exemplify the potential of palaeodosimetric dating methods mainly used in this study — mollusc shell-based electron spin resonance (ESR) and feldspar-based infrared optically stimulated luminescence (IR-OSL) — to chronologically organize the sequence of the Late Pleistocene palaeoenvironmental events, and to improve understanding of the palaeoenvironmental evolution during this period.

This paper discusses successive changes in the evolution of the fluvial system observed throughout the Blądzikowo Formation at the Mrzezino key site in northern Poland. The study focuses on the development of fluvial sedimentation during Marine Isotope Stage 7. The sedimentary record of the Pleistocene at the study site shows a well-developed sequence that is over 30 m thick. The Blądzikowo Formation shows a quick evolution of the fluvial system from a high-energy sandy braided river, to a meandering sandy river and, finally, to a low-energy meandering/anastomosing river with significant suspension settling. This transition is explained as a decrease in flow energy, increase in aggradation ratio and expansion of accommodation space during deposition time. A change in the fluvial system has not been manifested in the variations of the plant cover. Palynological analysis indicates that climate conditions were generally stable, cool and humid (boreal). Sediment transport occurred towards the N-NW, through a valley with a NW-SE axis. Infrared optically stimulated luminescence (IR-OSL) dating shows the sequence formed from 225.6 ± 17.2 to 210.5 ± 16.6 ka. Well preserved fluvial cycles and 35 m of thickness suggest the intensive accumulation of the Blądzikowo Formation with decreasing ratio of lateral erosion. It suggests an increasing influence of base level rise on evolution of fluvial system, mostly during MIS 7.

Paleoseismological and archaeoseismological research in the Katun Fault zone in Gorny Altai reveals soft-sediment deformation structures (SSDS) in Late Quaternary sediments that fill the Yaloman graben. SSDS (seismites) were produced by large paleoearthquakes (M ≥ 5–5.5) along the Katun Fault that occurred about 150 and 90 ka, in the 38–19 and 19–12.5 ka intervals, and after 12.5 ka. The event after 12.5 ka within the graben had a magnitude of Ms = 7.2–7.6. Traces of another event, shaking intensity I ≥ V (ESI 2007 intensity scale), timed in the range from the 3rd century BC to the 1st century AD, were discovered during studies of a Scythian necropolis at the Chultukov Log 1 site located within the Manzherok graben in the northern end of the Katun Fault. Burial mounds near a mountain slope at the site are damaged by colluvium. Rocks of the same colluvium are scattered over 25 m off the slope and deform burial structures (cairns and stone rings, and inner stone walls of grave chambers), as well as the primary anatomical position of buried bodies, including those in burials not damaged by colluvium from outside. Thus, the Katun Fault was an active structure generating large earthquakes from the Middle Pleistocene through the Holocene.

Dating of marine sediments and faunal remains they contain in stratotype and reference sections by the methods of infrared optically stimulated luminescence (IR-OSL) of K-feldspar, optically stimulated afterglow (OSA) of quartz, electron spin resonance (ESR), and 230Th/U provides new constraints on deposition in the Yenisei mouth during the Kazantsevo interglacial. The luminescence and U–Th ages in the 120–68 ka range and 93–70 ka ESR ages show that the deposition spanned the whole marine isotope stage (MIS) 5. The sediment structures and textures, grain sizes and mineralogy, and faunal records indicate tidal and shelf deposition environments. The sampled assemblages of marine mollusks comprise taxa that typically live in relatively shallow and warm water, as well as abundant subarctic and boreal species, including the Arctica islandica index species. The variations of faunal patterns, more likely, had facies rather than climatic controls, while the sediments were deposited during transgression, in a warm climate, when the area was ice-free.

Vilumaa, K.; Tonisson, H.; Sugita, S.; Buynevich, I.V.; Kont, A.; Muru, M.; Preusser, F.; Bjursater, S.; Vaasma, T.; Vandel, E.; Molodkov, A., and Jarvelill, J.I., 2016. Past extreme events recorded in the internal architecture of coastal formations in the Baltic Sea region. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 775–779. Coconut Creek (Florida), ISSN 0749-0208. The postglacial uplift and transgressive-regressive phases of the Baltic Sea have affected the formation and displacement of sandy accumulation forms in the region. The dune-ridge complexes preserve a geological record of past sea-level fluctuations, coastal evolution, and extreme events, and offer insights into major driving mechanisms. This study aims to improve methodologies for identifying different storm signatures in coastal deposits using examples from Estonia and ...

We report the discovery of the oldest evidence for human presence in the southeastern Baltic Sea region. This paper presents an overview of the Riadino-5 archaeological site in the lower course of the Sesupė River (Kaliningrad Oblast of Russia) and direct infrared stimulated luminescence (IRSL) ages for the culture-bearing sediments from the site, which place the time of occupation well within the range of Marine Isotope Stage (MIS) 3 (ca 57–26 ka). Luminescence ages were determined using the multiple-aliquot additive-dose technique, applied to sand-sized potassium feldspar. Four of the six IRSL samples from the site come from the cultural deposits, while two are from the surrounding sediments. The luminescence age of the deposits implies that human occupation of the southeastern Baltic Sea region occurred at least between 50 ka and 44 ka during the first half of MIS 3 and the Middle-Upper Paleolithic.

The sedimentary record of aeolian deposits and geomorphic features of the aeolian landforms of Northern Eurasia contain important information that allows us to better understand the climate and environments of the Late Glacial and Early Holocene periods. At the same time, the degree of scientific knowledge about the timing of aeolian activity, as well as the landscapes that existed during these periods, differs significantly for different parts of this vast territory. Data on the sedimentological record and age estimations of aeolian phases are practically absent for the periglacial zone of Western Siberia, in contrast to that of Europe. This paper presents the first data on the Late Quaternary fluvio-aeolian environments of the southwestern part of Western Siberia, using two sections as examples. Our methods included field investigations, analysis of grain-size and chemical composition, quartz grain morphoscopy and infrared optically stimulated luminescence (IR-OSL) and AMS dating. The obtained results show that aeolian sands are common covering deposits within the study area. Two stages of aeolian activity were identified: the first during the Boreal period (9.2&ndash, 10.2 ka BP), and the second during the Atlantic period, beginning near 7 ka BP.

Sand dunes are the most prominent subjects of geological and geomorphological interest along the Curonian Spit – a mega-barrier that separates the Curonian Lagoon from the Baltic Sea. To date, an assessment of various parameters of migrating dunes along the spit has been based on comparative analysis of old maps or aerial and satellite images, as well as geodetic measurements. These investigations have allowed assessment of dune dynamics over a relatively short historical period (~1700s to present). The most recent detailed investigations of the Dead (Grey) Dunes along the Lithuanian part of the spit using ground-penetrating radar (GPR) and magnetic susceptibility (MS) surveys, supported by a radiocarbon ( 14 C) chronological framework of palaeosols and infrared optically stimulated luminescence (IR-OSL) ages of sand horizons, have advanced our understanding of aeolian landscape evolution. The interpretation of dune activity and stability phases has been generally based on IR-OSL dating results of the sand layers located between radiocarbon-dated palaeosols. However, the influence of soil-forming processes on the IR-OSL dating results related to possible migration of natural radioactive isotopes via aeolian sand layers has not been previously considered. Hypotheses of dune reactivation and migration caused by abrupt regional climate shifts, catastrophic forest fires, anthropogenic influence, and more local forcings have been tested. An integrated approach to dune investigations has offered an estimate of the rates of sand accumulation and key phases of aeolian dynamics during both stormy and calm periods, as well as helped to extend the record of dune evolution to the mid-Holocene. The palaeoenvironmental and palaeodynamic reconstructions of the Dead Dunes suggest that this mid-Holocene phase of dune activity was of a local character and likely did not exceed several centuries.

The object of the study was the fluvio-aeolian sedimentary succession in eight sites located in the central part of the European Sand Belt, in Poland and NW Ukraine. Based on the lithofacies, pedological and morphoscopic analyses, the analyses of frost structures and grain size as well as the TL, IR-OSL and 14 C dating, three lithofacies complexes deposited at the turn of the Weichselian and Holocene were documented. The fluvial complex was deposited in the Pleniglacial within a sandbed braided river, which in the final stage of deposition of the complex was transformed into an anastomosing river. These rivers functioned in continuous permafrost coverage. The fluvio-aeolian complex was the result of aeolian deposition and fluvial redeposition, resulting from the degradation of continuous permafrost at the turn of the Pleni- and Late Glacial. These processes operated in the areas abandoned by regular flow. The aeolian complex was accumulated following the development of aeolian sand forms – sandy and silt covers as well as parabolic and longitudinal dunes, after the complete degradation of permafrost at the end of the Late Glacial and Holocene. Improving climatic conditions were expressed by the presence of fossil levels of initial gley soil in the roof of the fluvio-aeolian complex as well as poorly developed podzolic and colluvial soils in the aeolian complex.

During the past decades, a suite of radiocarbon (14C), infrared optically stimulated luminescence (IR-OSL), and electron spin resonance (ESR) dates were compiled on a variety of materials from the Curonian and Vistula lagoons and spits of the southeastern Baltic Sea. These dated materials generally included lagoon sediments and mollusc shells, along with samples of fossil fish remains, peat, wood, and water bicarbonates. A growing number of 14C dates (conventional and AMS) demonstrates disparities and contradictions with the associated IR-OSL dates and palaeobotanical investigations of contemporary materials. Detailed analyses of 14C, IR-OSL and ESR chronologies and experimental 14C dating of modern live molluscs and water bicarbonates from the Curonian Lagoon and its main tributary – Nemunas-Neris River system – reveals a substantial influx of “old” carbonates into the lagoon. As a result, the uncertainty of reservoir effect added a considerable error to the 14C ages. Moreover, fossil molluscs of the same species extracted from boreholes and outcrops yield significantly younger ages (up to several millennia) than the enclosing sediments. Both of these trends – aging and rejuvenation – highlight an urgent need for constraining the local reservoir correction (ΔR). Several scenarios are presented to explain the impact of vital effects on radiocarbon chronology of carbonates and to offer strategies to account for them in future studies.

The Netiesos section in southern Lithuania exposes a late Pleistocene sedimentary sequence at a depth of between 17 and 4 m. An interdisciplinary study of the section investigated the environmental changes that occurred in the study area during the greater part of Marine Isotope Stage (MIS) 5. Geochemical, thermoluminescence, palaeontological (plant macro-remain, diatoms, fishbones) and magnetic susceptibility analyses were performed on numerous sediment samples. Chronological control of the sequence was provided by electron spin resonance (ESR), infrared optically stimulated luminescence (IR-OSL) and conventional radiocarbon dating methods. This interdisciplinary approach enabled the subdivision of the section into stratigraphic units reflecting environmental changes. According to chronological data, the development of the Netiesos palaeolake began at the end of the Medininkai (Saalian) glaciation, which is thought to correlate with MIS 6, and continued up to the thermophilous deciduous forests phase of the subsequent last interglacial of MIS 5. Sediments of the final phase of the interglacial are missing, as are the initial and final phases of the following early Nemunas (Weichselian) cooling (MIS 4). The palaeomagnetic Blake Event was recorded in the interglacial sediments. One of the richest palaeofloras in the East Baltic region was observed representing the second half of MIS 5. The implications of the results for the regional late Pleistocene climato-chronostratigraphy are discussed.

The Kara Sea coasts were studied using comprehensive stratigraphic and geocryological methods. The paper presents the new analytical studies of ground ice and Quaternary deposits of Western Taymyr and presents the results of spore and pollen, foraminifera, grain-size, mineralogical, geochemical, oxygen isotopic, and other analyses. Several stratigraphic- geocryological transects from Yenisey and Gydan Bays enable us to refine the stratigraphy and palaeogeographical reconstruction of the environments and freezing of Late Pleistocene- Holocene sediments. Marine sedimentation conditions during the late Kargino time (MIS3) changed to continental conditions in MIS2 and MIS1. Marine sediments were frozen syn- and epigenetically with cryotexture and ground ice formation. Ice wedges formation corresponds to the end of the Pleistocene (MIS2) and during cooler periods of the Holocene.

The consistency of the dating results obtained by different methods, both absolute and relative, is investigated. The main absolute methods referred to in this article are the mollusc-based electron spin resonance (ESR) and feldspar-based infrared optically-stimulated luminescence (IR-OSL) dating methods used in the Research Laboratory for Quaternary Geochronology, Tallinn University of Technology. It was shown that the parallel comparative dating by these two methods yield, essentially, consistent results. U–Th age determinations were performed in some cases for better understanding of the uranium behaviour in the shells during their burial history. ESR and U–Th dating results obtained on one and the same shell-type, both marine and land snails, coincide well in the case if shells behaved as a close system during their burial history. It is also shown that the numerical dating results obtained on warm and cold climate-related deposits, correlate well with the corresponding palaeoclimate signals derived from continuous records of the climate and environmental evolution, constructed on the base of the most common of the relative dating methods used in Quaternary studies. Based on good consistency of the results obtained by all methods used in the present comparative study, we conclude that there is a good potential to improve our understanding of the middle to late Pleistocene palaeoenvironmental evolution in Northern Eurasia, with a special focus on the climatically highly sensitive Eurasian Arctic palaeo-shelf area.

1. IntroductionWe welcome Erdem Bekaroglu’s (E.B.) comments on our paper(Dogan et al., 2012) and the opportunity to discuss some importantaspects related to MIS 5a and MIS 3 high sea-level events notreflected in the paper. We have endeavoured to follow thecomments in the order of their presentation.2. Previous resultsWe are of the opinion that it can be a rather thankless task tosynthesize diverse and often contradictory data from all the avail-able sources. Therefore, where possible, we prefer to rely on ourown data obtained during the last three decades over the vast areaof Northern Eurasia (see, e.g., Molodkov and Bolikhovskaya, 2010,and references therein).As to Heinrich event (HE) 5, we would like to indicate that thecoral-based UeTh ageof this event (54.2e49.4 ka) maybe the rightone, in the case that three conclusions made by Lambeck et al.(2002, pp. 202e203) are accepted. Otherwise

article The available data of earlier investigations (Basalykas, 1965; Basalykas et al., 1976a,b; Kudaba, 1983) show that deposits of various origin and age are widespread in Asmena Upland and Lyda Plateau (South-Eastern Lithuania). They overlie a polygenetic dislodged marginal formations of the penultimate Medininkai (Warthe) glaciation. Pleistocene deposits in this area are often deformed by solifluction and fluvial erosion and penetrated by cryogenic ice-wedge pseudomorphs. Granulometric, geochemical and petrographic investiga- tions of the deposits have demonstrated that they are characterized by different sources of sedimentary material supply as well as different degrees of physical and chemical weathering. The alternate deposits preserved in the study area imply palaeoenvironmental changes associated with the different palaeoclimatic events. The Ca/Zr ratios in cover deposits testify that the upper beds usually experienced stronger chemical weathering that is associated with warmer climate. The cases of weaker weathering can be explained by

Glacial till and inter-till deposits exposed in the Lithuanian coastal region are evidence for multiple glacial advances during the Pleistocene. Stratigraphically, tills are the most important, prominent and well preserved deposits. However, despite the importance of these deposits, there is limited chronological control and it is widely debated whether they belong to one or another Pleistocene glaciation. The aim of the present study was to find features of the glacigenic tills, which allow us to temporally constrain these deposits, which are usually deemed to be undateable by luminescence methods. To achieve the goal, 15 samples from five different till beds and 12 samples from underlying sandy inter-till deposits from the same area were taken for analysis by feldspar-based IR-OSL technique. This paper presents the results, which suggest that the studied deposits, including glacial tills, are mostly of late Pleistocene age (MIS 5 and 4). We discuss analytical data obtained for these materials and implications for stratigraphic subdivision of the till-bearing deposits in the Lithuanian Maritime Region.

The time span of the past 200 ka has been marked by many large-scale global and regional climate changes, between warmer and cooler conditions. As is usually the case when studying the past, palaeoenvironmental data become scarcer with increasing age. Therefore, every detailed palaeoenvironmental record may be of special interest to Quaternary geologists in terms of palaeoenvironmental reconstructions, correlations and general stratigraphy of the Quaternary. In this paper we present a long palynological record of terrestrial flora and an ESR-dated marine record of global-scale climatic variation obtained from a loess–palaeosol sequence in the East European Plain and continental margin of Northern Eurasia for the time span starting from the penultimate glacial period correlating with Marine Isotope Stage (MIS) 6. These records show that in combination they have a potential of assigning warm/cold climate related deposits to the chronostratigraphically organised sequence of the late Pleistocene palaeoenvironmental events.

The potential use of a new ESR method for the dating of subfossil shells is discussed on an example from the northern part of the East-European Plain. A variant of the ESR technique, elaborated at the Institute of Geology of the Academy of Sciences of the Estonian SSR, is described and the Eemian age of the Boreal transgression proved.

Anomalous Fading of Ir-Stimulated Luminescence from Feldspar Minerals: Some Results of the Study An increasing amount of evidence shows that the use of feldspars in luminescence dating may suffer from significant age underestimates, which are thought to result from anomalous fading. In the hope of finding a solution to the problem we undertook physical investigations of kinetics and temperature dependencies of tunnel afterglow of these minerals. As a result, the method of the direct detection of the tunnel transitions from the dosimetric traps is proposed. Some other relevant results obtained are also presented and discussed. Particularly, the probable reasons of absence of effects of anomalous fading in the feldspar samples investigated in the present work are elucidated.

This paper presents a series of results obtained from the 22 m thick deposits of the late Pleistocene section at the Voka site, NE Estonia. The section has been intensively studied during the past few years to elucidate the dynamics of the late Weichselian palaeoenvironmental changes in the Baltic region. According to the results obtained, the sediments at the Voka site were deposited in presumably freshwater sedimentary basin, which existed at least during the whole pre-Late Glacial Maximum (LGM) period of late Pleistocene (MIS 5 to 3). One of the characteristic features of the deposits is the high uranium content (up to 23 ppm) in the upper part of the section studied. This study aimed to focus on the influence of potentially unstable environmental radioactivity on dosimetric dating results due to possible disequilibrium in the U decay chain. It was found that despite the high uranium content in the deposits, the dispersion of the dates obtained is surprisingly low. At the depths with the highest uranium content, only a moderate increase of the dispersion of the ages is observed.

Original materials of pollen analysis and ESR-chronostratigraphic studies provided a basis for reconstruction, chronological subdivision and inter-regional correlation of palaeoclimatic events and sediments of palaeo-shelf, glacial–periglacial and extra-glacial regions of Northern Eurasia within the scope of the Brunhes Epoch. Chronostratigraphic position of the identified palaeoenvironmental events and corresponding horizons in the composite chronostratigraphic column is established on the base of ESR-analyses of subfossil mollusc shells collected from marine, freshwater and terrestrial deposits. The palyno-chronostratigraphic record displays a sequence of 8 intervals (the Holocene included) of warm climate and high sea-level stands, when marine sedimentation occurred on palaeo-shelves, and 7 glacial epochs. The alternating intervals are either fully recorded as complete glacial-interglacial rhythms, or represented by a large enough number of consecutive climatic-phytocoenotic phases. The rhythmic regularity in the sequence of glacial and interglacial events has been inferred from detailed palynological data on reference sections of loess–palaeosol series in the centre of the East European Plain (Arapovichi, Otkaznoe, Likhvin, Strelitsa sections). A clear agreement between long pollen record, directly dated warm-climate-related deposits and other records of palaeoenvironmental evolution known from literature has been established for the upper 15 oxygen isotope stages (OIS 15 to 1). Finally, we come to a conclusion that the integrated climate-chronological sequence may be taken as a basis for inter-regional correlations of palaeo-shelf and terrestrial sediments within Northern Eurasia; it may be used as an intermediate link in the continent–ocean correlations.

Sand dunes are common along the sea coasts of Lithuania and in some regions of the mainland part of the country. Until recently, the age of the aeolian deposits was only approximate because of the lack of radiocarsbon-dating of soils buried in dune deposits. A relatively new alternative method to direct dating of organic-free deposits is infra-red optically stimulated luminescence (IR-OSL). Using this method, we investigated the sedimentary history of some Lateglacial and Holocene depositional sites of Lithuanian dunes. The samples for IR-OSL dating have been taken from boreholes (Manciagire, Smalininkai, Žalioji Giria) and outcrops (Manciagire and Ventes Ragas) in different dune massifs. The results indicate that the aeolian sedimentation in Lithuania started during the Younger Dryas. The termination of the aeolian processes in the continental part of Lithuania is correlated with the end of the Atlantic or the beginning of the Subboreal period; this can be explained by significant climatic changes during the Atlantic period. There were several periods of high aeolian activity during the Holocene, but these are asynchronous in different dune massifs and variations in the sedimentation rate occurred both vertically over the section and spatially across the massif.

In this paper the results of pollen analyses of the loess–palaeosol sequences (LPS) of the East European Plain are presented. Environment and vegetation evolution during the time of loess and soil formation has been characterized by pollen data of the reference sections of the Upper Oka (Likhvin–Chekalin section), the Upper Don (Strelitsa section), the Middle Kuma (Otkaznoe section), the Middle Dniester (Molodova and Ketrosy sections), and the Middle Desna (Arapovichi section) regions. Palaeomagnetic studies indicate that the sediment sequence studied spans at least the last 800 ka. The palynological climate proxies show a pattern of periodic variations comprising nine interglacial and eight glacial stages. On the basis of palynological results coupled with the electron spin resonance (ESR)-chronostratigraphic data on mollusc shell-bearing marine and terrestrial deposits, the reconstruction, periodization and distant correlation of palaeoclimatic events and deposits of glacial, periglacial and extraglacial zones of Northern Eurasia over the last 600,000 years have been carried out. Based on palaeoenvironmental evidence, it has been established that the full-interglacial conditions revealed are centred at about 580, 400, 310, 220 and between 145 and 70 ka. A broad correspondence between the long palynological sequence, directly ESR-dated warm-climate-related events and other palaeoenvironmental records described in the literature is noted at least for the 11 upper marine isotope stages (MIS 11–1).

The occurrence of sandy clay deposited in a warm marine environment just below the till of the last glaciation has created controversy about its age and stratigraphic position in the sedimentary basin of the Kola Peninsula. Data on marine microfauna, diatoms, malacofauna and pollen composition indicate that during the period when the sandy clay was deposited the climate was similar or even warmer than at present. According to 14C dates, sedimentation of the sandy clay occurred around 40 ka BP. Based on these data, some researchers have attributed these marine deposits to the third Late Pleistocene Belomorian (sensu Lavrova 1960) interglacial transgression. At the same time there are geological indications suggesting re-deposition of these subtill sediments. To solve this problem we have reinvestigated the subtill interglacial marine deposits from the Varzuga section (˜66.4° N and 36.6° E). Four different marine shell species and enclosing sandy clay sediments taken from the subtill marine unit of the section were dated by the electron spin resonance (ESR) and optically-stimulated luminescence (OSL) methods at about 103 and 104 ka, respectively. The results indicate that the subtill marine deposits belong to the first Late Pleistocene Boreal transgression that, according to our previous studies of the marginal areas of the Eurasian North, has occurred in the time interval from approximately 145 to 70 ka BP.

We reconstruct and correlate palaeoclimatic events and deposits from shelf, glacial, periglacial, and extraglacial zones of northern Eurasia over the last 600,000 years. The chronostratigraphical correlation of identified palaeoenvironmental and sealevel events and corresponding horizons is based on electron spin resonance (ESR) analysis of subfossil mollusc skeletal remains from marine, freshwater and Acheulian-bearing cave-site deposits. Over 230 shell samples from more than 40 sites along the continental margin of Eurasian north, in the Black and Caspian sea basins and terrestrial shells from a Lower Palaeolithic cavesite in the Northern Caucasus were dated via ESR to produce a late Quaternary geochronology. The Pleistocene composite section of the loess-palaeosoil formation includes two reference sections—Likhvin and Arapovichi—from the centre of the EastEuropean plain. The palyno-chronostratigraphic record is interpreted as the product of six warm-climate/high sea-level events including the current interglacial, and six glacial events. They are presented either as complete climatic rhythms of glacial and interglacial rank, or by considerable portions of climatic–phytocoenotic phases constituents of the rhythm. The full-interglacial conditions are centred at about 580, 400, 310, 220 and between 145–70 calendar ka. A broad correspondence between long palynological sequence, directly ESR-dated warm-climate-related events and other palaeoenvironmental records described in the literature has been noted for 11 upper oxygen isotope stages (11 to 1). The results obtained in this study exemplify the potential of integrated chrono-climatostratigraphic sequences in linking marine and terrestrial palaeoclimate records that may eventually span the whole Brunhes chron. D 2002 Elsevier Science B.V. All rights reserved.

The article presents new data on sedimentological structures, which have been discovered at the Ryadino archaeo­logical excavation in the northeast of the Kaliningrad District of Russia (the Šešupė River Valley). Tongue-shaped and dome-shaped diapir-like structures indicate liquefaction-induced features. As the most plausible reason, the earthquake-induced shaking is discussed. A preliminary estimation of the time interval for the seismic event covers the period from the early up to the late Holocene. The reasons for seismic activity in this region can be related to neotectonic movements (including glacio-isostatic rebound) as recorded in the southeastern Baltic Sea area of the Fennoscandian ice sheet margin zone. The relation between a palaeoseismic event and the essential changes in the hydrographic network in the region is also discussed.

Eight terrestrial shell samples from recent excavations at Treugolnaya (Triangular) Cave (Northern Caucasus) were analysed by electron spin resonance (ESR) to produce a chronology for the most ancient Acheulian-bearing layers of the cave-site. The lifetime of the 2.0012 centre used for dating is about 3]108 at 53C that allows to date the multi-level sequence of the cave-site at least in the range of the last one million years. The dating results obtained suggest that the "rst (from the bottom) archaeological layer, 7a, is likely to be about 583,000a old, and the next, 5b, is some 393,000 a old. These layers can be correlated with oxygen isotope stages 15 and 11, respectively. The estimates obtained imply that man presumably reached the Northern Caucasus at least as early as the beginning of stage 15, i.e. much earlier than generally recognised. The leaving of the cave by ancient man due to development of glacial environment during the subsequent stage(s) can probably be linked with the penetration of man to the southern areas of the East European Plain. ( 2000 Elsevier Science Ltd. All rights reserved.

The occurrence of Portlandia arctica shells in glacigenic sediments of Central Latvia had created a controversy in many publications about (1) their age ranging from the Holsteinian to the Late Weichselian and (2) the genesis of their enclosing sediments: glacial, glaciomarine or marine. Our reinvestigation of the main object of controversy, the Licupe site, leads to a conclusion that the sedimentary package of diamictons, clays and sands containing Portlandia arctica shells and marine microfossils is a large glacial raft that had been transported and deposited by the Riga lobe during the Weichselian. The electron spin resonance (ESR) ages on five sets of Portlandia arctica shells from the Licupe and Daugmales Tomēni sites range from 86.0±6.8 to 105.0±9.2 ka BP. These ESR age determinations and the cool climate indicators of the associated microflora and microfauna suggest that their source sediments, probably in the Gulf of Riga, are marine clays of Early Weichselian age, probably correlative to the Brorup Interstadial. In Central Latvia Portlandia arctica shells and their enclosing clay occur resedimented or translocated in glacial deposits during Weichselian glacial advances.

Freshwater gastropod (Lymnaea baltica) and brackish-water bivalve (Cerastoderma glaucum) shell samples from Ancylus Lake and Litorina Sea deposits on Hiiumaa Island (north-west Estonia) were subjected to ESR measurements. All L. baltica shells studied were composed of calcite and displayed typical multicomponent ESR spectra. C. glaucum shells normally show ESR spectra typical of aragonite with five radiation-induced lines. In the present work a C. glaucum with calcite-like spectra was encountered for the first time. The problem connected with accumulated palaeodose determination in shell fossils with unusual ESR spectra is highlighted.

The Klaipėda Strait is located between the Curonian Spit and the mainland coast of Lithuania. It links the Curonian Lagoon with the Baltic Sea. The Quaternary sequence is represented here by Pleistocene sediments formed during a few glaciations and interglacials. Its uppermost part is composed of Late glacial and Holocene sediments originating from different stages of the Baltic Sea development. One of the main problems of Quaternary geology in the vicinities of the Klaipėda Strait, as well as in the whole Lithuanian Coastal Area, is the reliable geochronology and stratigraphic correlation of sediments. To contribute to the solution of this problem, the infrared optically stimulated luminescence (IR-OSL) dating of the lacustrine inter-till sandy sediments was done during the engineering geological mapping of the Klaipėda Strait. The absolute majority of the IR-OSL ages obtained for the investigated inter-till sediments fall within the age range of marine isotope stages (MIS) 5d-5a. The subsequent more detailed examination of geological setting of Quaternary sequence has led to the assumption that the sampled inter-till sediments occur not in situ, i.e. they are found as blocks (rafts) in a thick till bed that have been formed by the ice advance during the Weichselian early pleniglacial maximum (MIS 4). This conclusion does not support the former standpoint that the till beds beneath the bottom of the Klaipėda Strait were formed during the Warthanian (Medininkai, MIS 6) glaciation.

Marine and terrestrial records spanning the Brunhes Chron (0-780 000 years) were synthesized using data from palaeoshelf, glacial, periglacial, and extraglacial zones of Northern Eurasia. The chronostratigraphic position of the identified palaeoenvironmental events and respective horizons in the composite chronostratigraphic column were established on the basis of electron spin resonance analysis of subfossil mollusc shells collected from marine, freshwater, and terrestrial deposits. Environ- ment and vegetation evolution during this period is characterized by pollen data from a series of spaced-apart reference sections on the East European Plain. The climate-chronostratigraphic record displays a sequence of eight intervals (the Holocene included) of warm climate and sea level highstand when marine sedimentation occurred on North Eurasian palaeo-shelves, and seven glacial epochs. A clear agreement between long pollen records and reliably dated warm-climate-related deposits was established for at least the last 600 000 years (from marine isotope stages 15 to 1). When integrated, these records have a potential of assigning warm/cold-climate-related deposits to the chronostratigraphically-organized sequence of the middle and late Quaternary palaeoenvironmental events.

This paper deals with the key problems of the ESR dating of subfossil mollusc shells — the estimation of the stored palaeodose of natural radiation. It is shown that the use of the analytical line (or peak in the integrated spectrum) at g = 2.0012 ± 0.0001 with the half-width 0.6 mT seems most advisable for the estimation of the relative concentration of radiation defects equivalent to the stored palaeodose in the calcareous shell skeleton. Optimal ESR spectrometer settings have been determined. Results of ESR dating of subfossil mollusc shells from Eemian deposits of Boreal transgression are discussed.

Due to relatively low thermal stability of radiation-induced centres in biogenic carbonate of subfossil molluscs (mean life θ = 3.7 × 105y at 10°C, g = 2.0012) correct dating of the latter by means of ESR-spectroscopy without considering natural relaxation of absorbed palaeodose my prove rather problematic. The long-term fading of palaeodose complicates correlation between absorbed natural radiation energy, and the value of the laboratory effect observed restricts the upper dating limit and may result in considerably younger ages on dating of the most ancient Quaternary samples. The present paper deals with the connection between the absorbed palaeodose value and the age of the sample, its dosimetric properties, as well as with the effect of different factors on the upper dating limit. Energetic parameters of CO3-3 centres (g = 2.0012) have been determined for the shell's carbonate: trap depth E = 1.52 ± 0.01 eV, frequency factor s = 8 × 1013 s-1, mean life θ = 1.14 × 106y at 5°C. Mathematical models of the palaeodose accumulation in nature are discussed. The author suggests palaeodosimetric equations for calculating the age of shells and some other materials. The equations may be applied both to ESR- and TL-dating.