期刊名称：Annales Universitatis Mariae Curie-Skodowska. Sectio B, Geographia, Geologia, Mineralogia et Petrographia
印刷版ISSN：0137-2025
出版年度：2004
卷号：LIX
出版社：Maria Curie-Sklodowska University, Lublin
摘要：The Dubanevyči profile of the Quaternary deposits is situated in the Ukraine, in the San and Dniester interfluve, near the European watershed (Fig. 1). It was described for the first time by Demedjuk and Demedjuk (1988a, 1988b). The authors of this paper undertook new studies of this profile. Geological investigations, analysis of heavy minerals composition, and several laboratory analyses (grain size distribution, contents of humus, Fe2O3, CaCO3) were made.TL ages were also obtained.
Based on all the obtained results, a synthetic lithologic-stratigraphic profile was composed. It contains 16 layers of deposits related on the following glacial periods: San 1, San 2, Liwiec, Odra, and Vistula (Fig. 2). The Lublin Interglacial was also identified. It is represented by the Koršiv pedocomplex, which consists of two paleosols. Both this pedocomplex and the Holocene soil are developed on loess. Deluvia of a paleosol from the Mazovia Interglacial were also found in the profile. The distinguished deposits are genetically differentiated, and represent the following environments: glacial - till with boulders (layer 9, Photo 3); glaciofluvial - sands (layers 8, 10); eolian - loess and loess-like deposits (layers 1, 2, 3, 11); lacustrine - fine sands and silts (layers 13, 14, 15); fluvial - sands (layers 4, 6); deluvial - clayey sand (layer 7); eluvial - coarse sand (layer 16). The deposits were transformed by pedogenesis and periglacial processes, and also affected by erosion and denudation, which led to the formation of numerous stratigraphic hiatuses and denudation surfaces, for example between the layers 1 and 2, 5 and 6, 10 and 11.
The results of TL measurements indicate that the till layer dates from the San 2 Glacial. The authors consider it to be the only one glacial period during which ice sheet covered the described area. Based on the studies of the Dubanevyči profile, the role of periglacial phenomena in the examined area can be discussed. A large frost wedge occurs in the deposits from the San 1 Glacial, and similar smaller structures - in the top part of the Liwiec Glacial deposits, and in the bottom part of the Vistula Glacial deposits. Traces of frost weathering, which resulted in deposit pelitisation, were also found. These facts indicate that periglacial climate, which characterized coolings of glacial rank in the examined area probably during the whole Pleistocene, was more severe that is has been thought till now, and permafrost occurred in the San 1 and San 2 Glacials.
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