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EN
Litho-, pedo- and palynological analyses constrained by radiometric dating of two loess-palaeosol sequences, Nahirne and Velyka Andrusivka, exposed in a cliff at the eastern edge of the Dnieper Upland, Ukraine, document regional environmental changes in the western marginal zone of the Dnieper lobe. The postglacial loess sedimentation cycle was initiated during MIS 8, immediately after the ice sheet recession. On the basis of palaeorelief analysis, subsequent morphogenetic stages of the original postglacial relief, associated with the modifying and masking role of the loess, and destructive slope processes were reconstructed. Periglacial steppe with consistently present scattered trees formed the Pleistocene landscape in the Middle Dniester area during the last three glacial periods. In such an environment, the following loess beds, correlated with marine isotope stages (MIS), were deposited: Dnieper (dn) - MIS 8, Tyasmyn (ts) - MIS 6, Uday (ud) - MIS 4 and Bug (bg) - MIS 2. During the last two warm periods: Kaydaky (kd) - MIS 7 and Pryluky (pl) - MIS 5, the landscape was not fully forested. As a result, the individual palynological features of these soils show a diverse character. The TL and OSL dates form a sequence with numerous inversions that are difficult to interpret. Although these data do not significantly influence the interpretation, they show that: 1) there are loesses that undoubtedly formed after the maximum extent of the ice sheet by short-distance transport of dust material from local fresh glacial deposits and the underlying Paleogene rocks; 2) date distortions result from the activities of an exceptionally rich pedofauna that has contaminated the material not only in the soil sections of the profile but also in the adjacent loess. It is possible to delimit a few stages of pedofaunal activity in each of the soil units.
EN
The distribution, age and correlation of Pleistocene sediments (1.806–0.01 Ma) is presented for an about 1200 km long geologic cross-section that extends from the Baltic Sea to the Black Sea and crosses the eastern part of the Polish Vistula drainage basin, the Dniester and Upper Pripyat drainage basins of the Ukraine, and also parts of the Russian Kaliningrad District andMoldova. In the vicinity of Warsaw, the oldest Pleistocene deposits comprise preglacial fluvio-lacustrine sediments of the Otvockian (Eburonian) cooling and Celestynovian (Waalian) warming stages that equate in the south with the Berezan and Kryzhaniv horizons, composed of loessy clays, silts and red-brown palaeosol. Along the cross-section, deposits of 8 main glaciations correlate with a similar number of main loesses (Narevian–Ilyichivsk, Nidanian–Pryazovsk, Sanian 1–Sula, Sanian 2–Tiligul, Liviecian–Orel, Krznanian–Dnieper 1, Odranian–Dnieper 2–Tyasmyn, Vistulian–Valday) that are separated by 7 main intra-loess palaeosols that developed during the main interglacial periods (Augustovian–Shirokino, Małopolanian–Martonosha, Ferdynandovian–Lubny–Solotvin, Mazovian–Zavadivka–Sokal, Zbójnian–Potagaylivka, Lubavian–Lublinian–Kaydaky–Korshiv, Eemian–Pryluky–Horokhiv). The first three interglacials are megainterglacials, which possibly include cool intervals during which ice sheets did not advance beyond Scandinavia. All glaciations and loesses, as well as interglacials and palaeosols that are considered asmain climatostratigraphic units of the Pleistocene of Central Europe, are grouped into climatic cycles and megacycles that correlate with corresponding units of Western Europe.
EN
26 units are described and correlated, representing the main climatic episodes during the Quaternary in Poland, Belarus and Ukraine. They comprise 13 cool and 13 warm intervals. The four oldest ones are Różcian (Olkhovskian, Siver), Ponurzycian (Grushevskian, Beregovo), Otwockian (Vselubskian, Berezan) and Celestynovian (Yelenynskian, Kryzhaniv); these correspond to Praetiglian, Tiglian, Eburonian and Menapian, respectively of the Early Pleistocene in the Netherlands. In Poland this part of the Quaternary is named the Pre-Glacial or the Pre-Pleistocene. The Mid and Late Quaternary (the glacial epoch in Europe) comprises 11 glaciations or global coolings, namely the Narevian in Poland (Zhlobynskian, Ilyichivsk), the younger pre-Augustovian (Rogachevian 1/2, Shirokino 1/2), Augustovian 1/2 (Rogachevian 2/3, Shirokino 2/3), Nidanian (Narevian in Belarus, Pryazovsk), Sanian 1 (Servetskian, Sula), Ferdynandovian 1/2 (Belovezhian 1/2, Lubny 1/2), Sanian 2 (Berezinian, Tiligul), Liviecian (Orel), Krznanian (Dnieper 1), Odranian+Wartanian (Dnieperian+Sozhian, Dnieper 2 = Tyasmyn), Vistulian (Poozerian, Valday); and 10 interglacials or global warmings: early pre-Augustovian (Rogachevian 1, Shirokino 1), Augustovian 1 (Rogachevian 2, Shirokino 2), Augustovian 2 (Rogachevian 3, Shirokino 3) ,Małopolanian (Korchevian,Martonosha), Ferdynandovian 1 (Belovezhian 1, Lubny 1), Ferdynandovian 2 (Belovezhian 2, Lubny 2), Mazovian (Alexandrian, Zavadivka), Zbójnian (Smolenskian, Potagaylivka), Lubavian (Shklovian, Kaydaky), Eemian (Muravian, Pryluky) and Holocene. All these units are correlated with oxygen isotope stages identified in deep-sea sediments, shown relative to the palaeomagnetic epochs and correlated with main cool and warm stratigraphic units of Western Europe. Particular attention was placed on correlation of glacial and lake deposits, loesses and palaeosols.
EN
Documented type sections (Vyazivok, Stayky, Uman, Troitskoye, Altestovo, Roxolany and Lebedivka) provide a basis for Pleistocene stratigraphy between Kiev and Odessa, and have been used to characterise the heavy mineral composition and part of the light fraction of the Bug loess in this area. These sections document an almost complete succession of climatic change during the last 780 ka, worked out mostly using loesses and palaeosols though also in the case of the first two sections, of glacial deposits. The heavy mineral composition of the Bug loess in these sections documents five mineral groups on the basis of their resistance to weathering and susceptibility to deflation and aeolian transport. Radar charts with particular mineral groups indicate mineralogical and genetic trends in the loesses. Moreover, in some sections the light fraction of the loess investigated contains derived microfossils (mainly foraminifers) of Cretaceous age, indicating source areas for the loess-forming material, and constraining the palaeowind directions. The data obtained allow distinction of three accumulation zones of the Bug loess in this area, reflecting loesses derived from different source areas and transported by winds from different directions. In northern sections (zone A), the Bug loess was accumulated by winds blowing from the west and north-west. More to the south (zone C), the same loess was accumulated by winds from the east and south-east. Loess preserved in zone B, between these areas, could be accumulated by winds from either of these directions.
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