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Lithological indicators of loess sedimentation of SW Poland

Krawczyk M., Ryzner K., Skurzyński J., Jary Z.

Contemporary Trends in Geoscience

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2017

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Vol. 6, iss. 2

94--111

EN

High-resolution grain-size investigations were carried out in two SW Polish loess sections: Biały Kościół (Niemcza-Strzelin Hills) and Zaprężyn (Trzebnica Hills). Each sequence was sampled by using the same methodology and samples were taken at 5 centimeters intervals. The particle size distribution was obtained with a Mastersizer 2000 laser, used for diffraction methods. From the obtained results the basic parameters and grain size indicators were calculated: Mz, Grain Size Index ratio, U-ratio and the percentage content of clay (< 4μm) and sand (> 63 μm). Both loess- soil sequences are composed of interfluve and slope loess facies and consist of five litho-pedostratigraphic units developed during the Late Pleistocene and Holocene: two loess units L1LL1, L1LL2 and three polygenetic fossil soils sets S0, S1 and L1SS1. The distance between these two profiles is about 60 km. Zaprężyn, as a section located more to the north, has almost no lower younger loess and higher level of weathering which could be related to proximity of this site to the Ice Sheet margin. The climate here was more extreme and harsh. What is more,the difference in development of soil L1SS1 can be observed: while in Biały Kościół pedogenesis process was slower and less disturbed than in Zaprężyn. The upper part of L1SS1 in Biały Kościół was deformed by gelifluction, frost heave and other periglacial processes. Mz indicator by the grain-size distribution in these sediments reflects subtle variations in the climatic system. Moreover, in Zaprężyn the content of sand fraction is higher than in Biały Kościół what can be the evidence of short episodes of strong winds during cold period of sedimentation. The aim of this paper is to compare two loess profiles by their stratigraphical and lithological similarities which are result of climate conditions and features of surrounding environment.

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Characteristic of till formation during the Baltija (Pomeranian) Stage of the Nemunas (Weichselian) Glaciation in Lithuania

Baltrunas V., Karmaza B., Dundulis K., Gadeikis S., Račkauskas V., Šinkunas P.

Geological Quarterly

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2005

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Vol. 49, No. 4

417--428

EN

Studies of the till structure and composition of the Baltija (Pomeranian) Stage of the Nemunas (Weichselian) Glaciation in Lithuania has enabled recognition of a multilayered till structure. This can be seen visually (colour, bed structure, interlayers, insertions of different composition and so on) and established from features determined by analytical and statistical methods (physical and mechanical properties, material composition, orientation and dip of longer axes of pebbles). Borehole log data from boreholes drilled during geological mapping showed heterogeneity within the subglacial till of the Baltija Stage and provided a preliminary picture of variations of its multilayered structure from S to N. This showed that two layers predominate in the subglacial till in the area of the South Lithuanian Phase while three layers are present in the area of the Middle Lithuanian Phase farther north. The petrographic composition of the gravel fraction as well as the orientation and dip of the long axes of pebbles measured in till beds in natural exposures and quarries further demonstrated the multilayered structure of the Baltija till. Research at key sections in areas of the subsurface extent of till of the East, South and Middle Lithuanian phases of the Baltija glacial recession confirmed the increase in the number of till layers from S to N. The physical and mechanical properties of the till also reflect its multilayered structure. Relative entropy values calculated for the grain-size frequency distribution of the Baltija till enabled evaluation of a change in its sorting along the direction of glacial ice advance from N to S. There is a correlation between the higher values of entropy of grain-size distribution and the rate of development of preferred orientation of longer axes of pebbles throughout the till section vertically. The formation of themultilayered structure of the Baltija till is ascribed to cyclic dynamics of the subglacial processes associated with the receding ice sheet; consequently, the number of subglacial till layers may be related to the marginal moraine ridges of different phases left by oscillation of the ice sheet margin during glacial recession.

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The problem of the Last Glaciation extent in Central Poland

Petera J., Forysiak J.

Geological Quarterly

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2003

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Vol. 47, No 4

357-366

EN

The maximum extent of the last ice sheet near Konin, Koło and Turek has been controversial. Investigations carried out in the Warta River has shed light on this problem. The Krzyżówki, Koźmin and Smulsko sites show fluvial deposits laid down in an extraglacial, periglacial environment during the Vistulian Glaciation. The northernmost site, Krzyżówki, shows an influence of proglacial waters, expressed by the supply of fluvioglacial material. The findings suggest that the last ice sheet did not overpass the Berlin-Warsaw Pradolina east of Konin and thus did not enter the Turek Plateau or the Uniejów Basin.

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Stratigraphy and sedimentology of the Bug loess (Pleistocene: Upper Vistulian) between Kiev and Odessa (Ukraine)

Chlebowski R., Gozhik P., Lindner L., Łanczont M., Wojtanowicz J.

Geological Quarterly

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2003

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Vol. 47, No 3

261-268

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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Derived marine microfossils in loesses of the last glaciation and their significance in the reconstruction of loess-forming processes in central-eastern Europe

Paruch-Kulczycka J., Chlebowski R., Lindner L.

Geological Quarterly

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2003

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Vol. 47, No 2

119-132

EN

Documented examples of type sections with Pleistocene deposits in southern Poland (Tłumaczów, Branice, Wożuczyn, Tyszowce, Hrubieszów) and southwestern Ukraine (Bojanice, Horokhov, Zhorniv) indicate that loesses of the last glaciation (Vistulian, Valdayan) contain derived marine microfossils of Cretaceous age. The microfossil assemblages studied are richly represented by foraminifers, which are mostly well-preserved, and derived mainly Cretaceous, forms. Suitable Late Cretaceous exposures are nearby, around data shows that these rocks and their debris, and the overlying Pleistocene tills and sands, which are older than the loesses, represent one of the main sources of the loess silt. This fact and the heavy mineral content are evidence of the participation of local material in loess-forming processes in central-eastern Europe. The spatial distribution of the sections studied in relation to the determined sources of loess material indicate that the accumulation of the loesses took place mainly in the presence of western and/or northwestern winds in the lower parts of the atmosphere.

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Profile wiertnicze osadów czwartorzędowych na Ornaku oraz ich znaczenie w badaniach nad ostatnim zlodowaceniem w Tatrach Zachodnich

Kenig K., Lindner L.

Przegląd Geologiczny

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2001

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Vol. 49 nr 12

1180-1185

PL

Przedstawiono wyniki badań litogenetycznych osadów czwartorzędowych pobranych przy pomocy trzech, pierwszych na obszarze Tatr, otworów wiertniczych zlokalizowanych na Polanie Ornak w górnej części Doliny Kościeliskiej. Z uzyskanych tą drogą materiałów wynika, że zachowane są tu trzy warstwy (poziomy) gliny morenowej, przedzielone nieglacjalnymi osadami różnej genezy. Na podstawie charakterystyki granulometrycznej oraz mineralogiczno-petrograficznej wykazano, że wymienione warstwy gliny morenowej mogą reprezentować trzy fazowe nasunięcia lodowców, a osady dzielące mogą reprezentować dwie interfazy w obrębie stadiału Białki ostatniego (würm, vistulian) zlodowacenia tatrzańskiego.

EN

The this paper presents the results of lithogenetic investigations of Quaternary deposits discovered for the first time bv three boreholes located at the Polana Ornak in the upper part of the Kościeliska Valley. Three till horizons separated by non-glacial deposits of different origin were recognized in the material obtained. Granulometric and mineralogical-petrographic analysis suggests that these till horizons may be ascribed to three phases of glacier advance, whereas the interbeds to two interphases within the Białka stadia! of the last (Wiirm, Vistulian) glaciation in the Tatra region

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Zróżnicowanie roślinności Polski u schyłku ostatniego zlodowacenia

Madeyska T.

Studia Geologica Polonica

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1998

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Vol. 113

137-180

PL

Zestawiono dane dotyczące roślinności późnego vistulianu na ziemiach polskich, pochodzące z kilkudziesięciu stanowisk osadów organogenicznych, opracowanych metodą analizy pyłkowej i analizy makroszczątków roślinnych. Już dla starszych, poprzedzających allerřd części tego okresu, mimo małej ilości datowanych stanowisk, otrzymano obraz regionalnego zróżnicowania roślinności. Obraz uzyskany dla dwu wybranych, charakterystycznych okresów, a mianowicie młodszej, optymalnej pod względem klimatycznym części allerřdu i ostatniego przed holocenem wahnięcia zimnego, czyli młodszego dryasu, uzyskany dzięki większej ilości danych, jest dokładniejszy. Stwierdzono zróżnicowanie gęstości pokrywy leśnej i gatunkowego składu zbiorowisk zarówno leśnych, jak i stepowo-tundrowych w kierunku z północy na południe, zależne nie tylko od rożnic termicznych, ale i stopnia rozwoju gleb wynikającego z ich wieku, czyli czasu, jaki upłynął od momentu odsłonięcia osadów spod pokrywy lądolodu, a także od odległości od ostoi. Zmiany składu zbiorowisk w kierunku E-W są odzwierciedleniem stopnia kontynentalizacji klimatu. Ogólny obraz roślinności regionalnej przedstawiono na mapach, natomiast lokalne jej zróżnicowanie, zależne od warunków topograficznych i rodzaju podłoża, na schematycznych przekrojach ilustrujących wybrane charakterystyczne stanowiska.