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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.

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.

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.

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.

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

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.

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.

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.