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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.

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 ...

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 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.

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.

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.

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.