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A summary of published and unpublished data on the stratigraphy of the late Early Pleistocene (Eopleistocene) of the Southern Urals region is presented in this paper. The summary follows previous reviews about the characteristics of the Pleistocene deposits of the easternmost part of Europe. The improvement and unification of the regional Quaternary stratigraphic scheme is the main aim of these investigations. In this paper we describe deposits of different origin, which constitute the regional stratigraphic units (Tyulyan, Raevka, Udryak, Khlebodarovka, Dombarovka, Blagovar and Oktyabrsky Horizons), are characterized. During the late Early Pleistocene (Eopleistocene), the Southern Fore-Urals region was characterized by continental climate conditions and by four phases of incisions of the hydrographic network that were related to regional uplift, as well as to the lowering of the base level and the subsequent regression of the Late Akchagylian Sea. Fossil molluscs, ostracods, mammals and pollen are used for the reconstruction of the palaeoenvironmental conditions and the biostratigraphical positions of the main localities. During Raevka, Khlebodarovka and Blagovar times, the climate was cool, and forest-steppe landscapes with prevalent open spaces existed. The climate during the Tyulyan, Udryak, and Dombarovka and Oktyabrsky times was warm, and during these periods, the areas of deciduous and coniferous forests expanded in the forest-steppes. The molluscan fauna of the Early Eopleistocene was a transitional fauna from the Pliocene to the Quaternary because the wet and warm climate, which was favourable to the Pliocene mollusc species, continued in the Southern Fore-Urals during the Early Eopleistocene. The mammalian assemblages are the basis for the biostratigraphical subdivision. The deposits are biostratigraphically correlated to the Lower Eopleistocene on the basis of the appearance of the first unrooted voles Allophaiomys and Prolagurus together with late species of the Mimomys genus. At the end of the Eopleistocene, the unrooted voles Terricola and Lagurina were numerous , the first Microtus appeared , late species of Mimomys were not numerous, and Archidiskodon trogontherii appeared in the mammal faunas of the region. The small mammals of the Tyulyan and Udryak times represent the Odessa faunal assemblage. The mammal fauna of the Oktyabrsky time corresponds to the Tiraspol faunal assemblage. The units are correlated with the Upper Villafranchian – Galerian stages interval in the Western European stratigraphical timescale. [ABSTRACT FROM AUTHOR]

Abstract: This paper is a synthesis of the previously published and unpublished materials dealing with the stratigraphy of the Upper Pleistocene (Upper Neopleistocene according to the Russian stratigraphic scheme) of the Southern Urals. It is the second review about the characteristics of the Pleistocene deposits of the easternmost part of Europe. It follows a previous paper concerning the biostratigraphy of the Late Middle Pleistocene of this region. The deposits which constitue the regional stratigraphic units are characterized. The results of the mammalian, malacological and palynological investigations as well as the radiocarbon data provide the basis for the stratigraphical subdivision and the reconstruction of the palaeoenvironments. The main geological and biotical events of the Southern Urals region which took place during Late Pleistocene are characterized in the paper. Erosional processes became active at the beginning of Kushnarenkovo time when uplift took place in the Urals and when the Late Chosarian regression began on the Caspian Sea basin territory. Fluvial deposits can be observed at the base of the second terrace which developed above the floodplain. A soil was formed on the subhorizontal surfaces. Forest-steppe and steppe landscapes characterized this interval. The climate was warm and humid. The Saigatka horizon formed under cold conditions. Slope processes and solifluction were the main relief-forming processes and fluvial erosion processes became weaker. Floodplain sediments accumulated in the river valleys and formed the upper parts of the second terraces above the floodpain which were intensively eroded. The plains were covered by steppe and the mountainous areas were occupied by tundra and forest–tundra landscapes. The next erosional cycle began during the following Tabulda period, because of the lowering of base level of the erosion and increased uplift of the territory. The fluvial sediments now form the lower parts of the first terraces above the floodplain. A soil was formed on the watersheds. Sites contain Late Palaeolithic artifacts. The floral association was close to Southern Uralian flora of the present-day. The climate was moderately warm in the plains and drier and cooler in the mountains. The subsequent Kudashevo event can be correlated with the Late Glacial when the climate became colder. Loess-like sediments and floodplain deposits form the upper parts of the first terrace above the floodplain and cover the watersheds, where they contain cryogenic structures. The climate was moderately cold. Late Palaeolithic sites attributed to the Kudashevo time are known in the Southern Urals region. The stratigraphical positions of the main Upper Neopleistocene localities of the Southern Urals are discussed. The Southern Urals subdivisions are correlated with the Western European stratigraphical scheme (Eemian–Weichselian interval). [Copyright &y& Elsevier]

Abstract: A description of the different layers deposited in La Haute Ville and Bréhat sites is given. Methodological considerations and comparisons with Russian, French and Netherlands stratigraphic scales are summarized. Malacological study shows the existence of shells deposited during the Early, Middle and Late Weichselian. In La Haute Ville, the upper part of the Lower and Middle Weichselian contains four soils which developed above an aeolian dune. Four malacozones have been separated. The groups of molluscs were classified according to their modern ecological preferences. The upper part of La Haute Ville Formation is observed in the lower part of the La Haute Ville cliff. This aeolian accumulation is completely decalcified. There is no fauna. The presence of colored quartz implies the existence of a warm climate. By comparison with other dunes of Brittany, it could be dated to the Early Weichselian. Comparison between the onshore and offshore data shows that the dune has never been as rich in carbonates as the loess or loess-like deposits. The Port Morvan Formation consists of four different soils interlayered with loams. All the soils are located at the level of the dome-like top of the dune. The disappearance of the soils towards the west and the east is associated with an undulation of the dune. The existence of four soils and the presence of molluscs living under broad leaved forests suggest a moderate climate. The cooling of the climate started at the end of the Port Morvan formation. These data allow correlation of this formation with the Middle-Lower Weichselian. The formation of Sables d’Or les Pins corresponds with true loess. It was deposited above the Port-Morvan formation which displays a clear erosion of its top. The top of this formation was affected by the development of a Holocene soil. A light grey layer represents a podzolic horizon. The lower boundary of these layers is affected by thermokarst. Because of their location, their aeolian origin, the existence of thermokarst, the mollusc assemblage and the dating already obtained elsewhere, this section is attributed to the Upper Weichselian. The Holocene deposits are represented by a podzolic soil and slope deposits, which formed during moderately humid conditions. It covers a dark grey soil made of colluvium containing charcoal and prehistoric to recent artifacts, which possibly formed in a forest or bush environment. [Copyright &y& Elsevier]

Abstract: The evolution of the mollusc fauna found in the easternmost part of Europe was affected by three main stages of development during the Quaternary. The Early Eopleistocene mollusc assemblage consists of rare terrestrial and numerous freshwater species with numerous thermophilic (Pliocene) species. The Late Eopleistocene – Early Neopleistocene is characterized by terrestrial and freshwater molluscs with few warm stenothermic Pliocene species. The Early Neopleistocene – Holocene assemblage is characterized by terrestrial and freshwater molluscs of modern affinities. [ABSTRACT FROM AUTHOR]