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Investigations of the unconsolidated Upper Pleistocene – Holocene cave deposits of the Southern Urals resulted in detailed biostratigraphical and palaeoenvironmental data. Landscapes of this area have a mosaic character. The forests have regional features developed at the transition of Eastern European broadleaved-dark-coniferous taiga and the Southern-Uralian light coniferous forests. The modern mountain mixed forests appeared during the end of the Holocene. The forest-steppes were widespread during Late Neopleistocene – Holocene. The forest vegetation existed during the warm periods (Tabulda, Middle-Late Holocene) and areas covered by forest were reduced during the cold intervals (Kudashevo, Early Holocene). However, refugia of broad-leaved flora existed in the territory of the Southern Urals even during coldest periods. The Late Pleistocene and Holocene mollusc species are Holarctic species that occur in forest-steppe, forest and intrazonal (river banks) ecological biotopes. The Late Pleistocene and Holocene amphibian associations found in caves are characterized by species that prefer forest biotopes. The reptile faunas contain species which inhabited open areas. The Pleistocene and Holocene fish fauna is a characteristic freshwater fauna occurring in a temperate zone: all species currently inhabit the European rivers. The Pleistocene and Holocene avifaunas include species that occur in the modern ornithological faunas of Northern Asia, Central and Northern Europe. The Late Pleistocene fauna was dominated by species that inhabited open and semi-open landscapes whereas, during the Holocene, species that preferred closed biotopes dominated the bird fauna. During the Late Pleistocene and Early Holocene disharmonious small-mammal faunas existed in the central and northern parts of the Southern Urals. These faunas included steppe and semi-desert species; lemmings are rare. In the southern part of the Southern Urals and in the Trans-Urals lemmings are absent. Starting from the Middle Holocene there is a gradual change of small-mammal communities. In the Southern Urals forest species replace the predominance of steppe species, and only in the Trans-Urals the steppe small mammal fauna preserved. The modern small-mammal faunal community appeared in the latitudinal part of the Belaya River valley at the end of the Late Holocene. There were relatively little changes in the Southern Urals large mammal fauna at the end of the Late Neopleistocene – beginning of Holocene. The large mammal fauna consisted of eurybiotic species and species that inhabit open landscapes. Species that prefer forest landscapes appeared at the end of the Early Holocene – beginning of the Middle Holocene. Modern large mammal species appeared during the second half of the Late Holocene. [ABSTRACT FROM AUTHOR]

A summary of published and unpublished data on the stratigraphy of the Early Pleistocene (Palaeopleistocene) 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 stratigraphical scheme was the main aim of these investigations. Deposits of different origin, which constitute the regional stratigraphical units (Zilim-Vasilyevo, Akkulaevo and Voevodskoe), are characterized. Malacological data form the base for the biostratigraphical subdivision. At the beginning of the Early Pleistocene, an ingression of the Akchagyl Sea (modern Caspian Sea area) began in the Zilim-Vasilyevo time, which developed as much as possible during Akkulaevo time, and then shortly re-emerged after regression into the territory of the Southern Fore-Urals during Voevodskoe time. During the Early Pleistocene (Palaeopleistocene), the Southern Fore-Urals region was characterized by continental climate conditions, which were influences by the wideapreaded brackish-water gulf of the Akchagyl Sea. Fossil molluscs, ostracods, mammals and pollen are used for the reconstruction of the palaeoenvironmental conditions and the biostratigraphical position of the main localities. The units have been correlated with the Gelasian stage of the Western European stratigraphical timescale. [ABSTRACT FROM AUTHOR]

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]

Study of the altitudes of the lowest part of the Upper Cretaceous-Eocene and Aktschagylian-Quaternary stratigraphic ensembles known on the western slope of the Southern Urals evidences the existence of an East-West elongated dome which follows the N53° latitude. This ridge is superimposed at depth with the remnants of the Sernovodsk-Abdulino Aulacogen and with the Belaya tear fault, which support the existence of a recent rejuvenation of these old structures. North of these disruptions the Southern Urals display a clear bent towards the East. Detailed microstructural studies show that this curvature is associated with a typical stress pattern which suggests the existence of an indentation of the fold belt by the East European craton. The hypothesis of an Ufa indenter is not supported by an equivalent East-West deep fault north of the bend. However, a long N100° magnetic anomaly, interpreted as a shear zone, suggests that the indenter is a reality. Quaternary uplift and crustal thickening at its front as well as seismological data support our interpretation. It is not stressed that the curvature of the Urals observed at 56° latitude results solely from this recent indentation. It is only assumed that the actual indentation is rejuvenating a former unevenness which existed before in the East European craton. Study of the inner part of the indenter shows that this type of structure is not necessarily rigid and undeformed. Some of the structures described on the URSEIS deep seismic line could be much younger than previously expected. [ABSTRACT FROM AUTHOR]

Abstract: This paper is a synthesis of previously published and unpublished materials dealing with the stratigraphy of the Holocene deposits of the Southern Uralian region (easternmost part of Europe). Results of the mammalian, amphibian, reptilian, malacological, and palynological investigations as well as radiocarbon data provide the basis for stratigraphical subdivision and reconstruction of the palaeoenvironments. The Holocene is represented by the Agidel Horizon with three subhorizons. The Holocene deposits form the high and lower flood plain terraces and the unconsolidated deposits in the caves. The vegetation development is based on Betula–coniferous forests at the beginning of this interval, which were replaced by Pinus–Picea forests with broad-leaved trees admixture (Early Holocene). At the beginning of the Middle Holocene birches decreased and the broadleaved trees and Picea increased in the forest compositions. The climate was warmer and more humid than the modern one. During the Late Holocene the type of vegetation was close to the modern one. Picea–Pinus–birch-tree forest was growing in the northern part of the Southern Fore-Urals with broad-leaved trees in the southern part. The percentage of open woodlands with Artemisia–Chenopodiaceae–herbage associations increased towards the end of that time. The mollusc fauna is represented by terrestrial and freshwater species. The variety and quantity of the terrestrial species increased compared with the Late Neopleistocene. The main part of the modern amphibian fauna of Southern Urals was formed during the Early Holocene. Modern amphibian fauna developed at the end of the Late Holocene and is represented by forest species. The modern fauna of reptiles of the Southern Urals formed at the end of the Late Holocene when steppe species disappeared. Nowadays, steppe biotopes exist in the southern part of this area. In the Southern Urals, the Early Holocene small mammal steppe biotopes were replaced by the modern forest biotopes. In the Trans-Urals the faunas were steppe species throughout the period. The Holocene large mammal fauna was characterized by the transition from the Mammoth to the Holocene complex when Late Pleistocene species disappeared during the Early Holocene. [Copyright &y& Elsevier]

Abstract: The altitudes of the lowest part of the Upper Cretaceous-Paleogene and Plio-Quaternary stratigraphic ensembles known in the Paleo-Volga basin and in the Paleo-Urals have been computed and represented at the same time for comparison. These two surfaces indicate an east–west elongated dome which follows 53°N on the western slope of the Southern Urals. This ridge is superimposed at depth with the remnants of the Sernovodsk-Abdulino Aulacogen and with the Belaya tear fault, which supports the existence of a recent rejuvenation of these deep basement disruptions. The 3D reconstruction shows that the two surfaces display the same type of uplift at around 52.50°N, 56.50°E. The variations in altitude of the two surfaces have been sampled along two sections running at the same longitude. When the two profiles are superimposed, the “post-Cretaceous and Paleogene” curve is higher. This result suggests that the uplift started after the Paleogene and continued until nowadays. Calculation of the local amount of uplift after the Aktschagylian considered the difference between the maximum uplift of the surface and a regional trend corresponding with the almost horizontal surface of the former deposits. In these conditions, the deformation affecting the Aktschagylian-Quaternary ensemble reaches 175 m. Since the measured post Cretaceous–Paleogene uplift incorporates also the Pliocene-Quaternary uplift, before the Pliocene the uplift only reached 23 m in altitude. This result gives an idea of the irregularity of the topography that the Aktschagylian transgression had to face. This result also suggests that the Pliocene-Quaternary amount of uplift was 6 times larger than the former one. [Copyright &y& Elsevier]

Abstract: Numerous caves and terraces with late Late Pleistocene (Upper Neopleistocene according to the Russian stratigraphic scale)–Holocene deposits are located in the Lemeza River valley in the surroundings of the Atysh waterfall, the native reserve territory of the Bashkortostan Republic. Lemeza River runs in the southern part of the western slope of the Urals and belongs to the Belaya River valley system (Russian Federation). A summary of the biostratigraphical investigations between 1992 and 2007 in this area is given. Deposits of cave and fluvial origin are characterized in the framework of the regional stratigraphy. The results of mammalian investigations and radiocarbon dating provide the basis for the stratigraphical subdivision. Palynology, mollusca, fishes, amphibian and reptiles are used for the reconstruction the palaeoenvironments. The Southern Urals stratigraphic subdivisions are correlated with Western European (Weichselian-Holocene), Eastern European (Russia) (Leningrad–Ostashkov–Shuvalov) and Uralian (Nevyansk–Polar Urals–Gorbunovsky) stratigraphic schemes. [Copyright &y& Elsevier]

Abstract: A summary of published and unpublished materials on the stratigraphy of the Late Middle Pleistocene (Middle Neopleistocene according to the Russian stratigraphic scheme) of the Southern Urals region is given. Deposits of different origin in the regional stratigraphic units are characterized. The results of mammalian investigations provide the basis for the stratigraphical subdivision. Mollusca and palynology are used for the reconstruction of the palaeoenvironments. The stratigraphical positions of the main Middle Neopleistocene localities and precise definitions of the stratigraphical scheme of the Southern Urals region are discussed. The Southern Urals subdivisions are correlated with the Western European stratigraphical schemes (Holsteinian–Saalian interval). [Copyright &y& Elsevier]

Abstract: Quaternary loess-like deposits occur in the Southern Ural region. The loess-like deposits attributed to the Upper Neopleistocene (Kudashevo horizon) are the most widespread and comprehensively studied. Pollen spectra studied in the loess-like Kudashev (late Valdai) deposits suggest dominance of meadow-steppe communities with various herbs, Artemisia and Chenopodiaceae; there existed also forest-steppes with Alnus, Betula and Pinus. [Copyright &y& Elsevier]

Abstract: At present there are more than 15 Palaeolithic type localities in the Southern Urals region. Most of these are located in karst cavities in the mountain area. In the flat part of the country, Palaeolithic type localities are extremely rare and are situated in the deposits of the second river terraces. Results of biostratigraphical investigations of the main localities are given in this short review. [Copyright &y& Elsevier]