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1

The provenance of erratic pebbles from a till in the vicinity of the city of Radom, central Poland

Strzelecki Piotr Jan

Geology, Geophysics and Environment

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2019

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Vol. 45, no. 1

21--29

EN

Petrographic analysis, including the indicator erratics count method of coarse pebbles (20–60 mm), was performed for the first subsurface layer of the glacial till in the vicinity of the city of Radom. Crystalline rocks comprise 60% of the sample, whereas carbonate and clastic sedimentary rocks total 18% and 15%, respectively. Among the crystalline rocks, 14% clasts were identified as indicator erratics. The majority of the indictor erratics originated from the Åland region (63%). Significant contributions were also derived from the central Baltic Basin (12%), Ångermanland (9%) and Uppland (9%) regions. Trace amounts are recorded from the northern Baltic, Dalarna and Småland regions. The spatial distribution of crystalline erratic source areas suggests material incorporation into an ice sheet mainly from central-eastern Fennoscandia. The indicator assemblage composition indicates the Odranian (MIS 6) origin of the till. The majority of the erratic sedimentary rocks were derived from the central and southern Baltic Basin while local rocks comprise a minor proportion. The relatively low carbonate clasts content indicates that the till was affected by partial decalcification resulting from post-depositional chemical weathering. This study supplements the results on erratic pebble provenance in the glacial tills of Middle Polish Glaciation Complex in Poland.

2

Determination of geotechnical properties of marine clay from the Słupsk Bank

Juszkiewicz P., Załęski K., Dyl K., Staszewska K.

Biuletyn Instytutu Morskiego w Gdańsku

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2017

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Vol. 32, No. 1

123--128

EN

For the purpose of this paper, laboratory tests on clay samples, collected at the Słupsk Bank with the use of a vibrocorer, were carried out in the Geotechnical Laboratory of the Maritime Institute in Gdańsk. This study aims to determine the geotechnical properties of the above-mentioned soils. Oedometer and classification tests were conducted on the selected specimens. Strain properties, secondary compression index and undrained shear strength were determined for the material. The impact of vibrocoring as a sampling technique on the obtained results and recommendations for application of these results were also described.

PL

Na potrzeby niniejszego artykułu, w Samodzielnym Laboratorium Geotechniki Instytutu Morskiego w Gdańsku, przebadano próbki iłów pobranych za pomocą wibrosondy z obszaru Ławicy Słupskiej. Celem badań było określenie parametrów geotechnicznych wspomnianych gruntów. Przeprowadzono badania edometryczne oraz wykonano badania klasyfikacyjne. Dla wybranych próbek określono parametry odkształceniowe i wyznaczono współczynnik ściśliwości wtórnej oraz określono wytrzymałość na ścinanie w warunkach bez odpływu. Opisano również wpływ pobierania próbek wibrosondą na uzyskane wyniki oraz pewne zalecenia dotyczące wykorzystywania wyników.

3

Quaternary deposits and weathered bedrock material as a source of dangerous radon emissions in Estonia

Petersell V., Jüriado K., Raukas A., Shtokalenko M., Täht-Kok K.

Geologos

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2015

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Vol. 21, No. 2

139--147

EN

The risk of dangerous radon emissions in Estonia is high, being among the highest in Europe. In almost 33 per cent of Estonian land area, the content of radon in soil-contained air exceeds the safe limit for unrestricted construction (50 kBq/m3). In such high radon-risk areas the concentration of radon in soil-contained air ranges from 50 to 400 kBq/m3, in a few cases reaching up to 2,100 kBq/m3 exceeding the permitted level for residential areas. The situation is particularly serious in the northernmost part of the country, where uranium-rich graptolite argillite (Dictyonema shale) and the Obolus phosphorite are close to ground surface and their particles are constituent parts of Quaternary deposits. Radon emissions from bedrock have been investigated in detail, but to date Quaternary strata as a source of radon emissions are poorly studied. According to our measurements the highest concentrations of radon are related to tills containing clasts and fines of graptolite argillite and phosphorite. Glacial deposits include also granitoidal material, containing U, Th and K, which have been transported by glaciers from the outcrop areas of crystalline basement rocks in Finland and the Gulf of Finland. Due to weathering, outwash and repeated redeposition other genetic types are poorer in radioactive elements and they are weaker sources of radon.

4

Basal till and subglacial conditions at the base of the Upper Odra Lobe (southern Poland) during the Odranian Glaciation

Salamon T.

Geological Quarterly

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2014

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Vol. 58, No. 4

779–-794

EN

The objective of this contribution is detail characteristics of the basal till and the conditions in the base of Upper Odra Lobe. The lobe was formed in a foremountain area. Its central part was a Niemodlin Plain and the W part of the Racibórz Basin, surrounded by areas that have a much more varied relief.Particular attention is paid to the conditions at the ice sheet base, generatingthe dynamics ofglaciermovement. The study is based on analysis of the basal till. Three sites with basal till lying on different types of substratum (more typical for the study area) are presented. The basal till of the Upper Odra Lobe is characterized by spatial variations. Different intensities of its deformation indicate that large lateral differences in conditions occurred in the lobe substratum. The lithology controlled the rate of basal water pressure, and thus the strength of both the subglacial sediments and the ice-bed coupling. Various strain rates in the till profiles indicate that the conditions at the ice-sheet base also changed with time. The ice sheet was highly mobile, even on the coarse-grained substratum. The low permeability of the Quaternary substratum, and the relatively small thickness of the Quaternary sands and gravels resulted in a high water pressure at the ice-sheet base. The movement of the Upper Odra Lobe was concentrated in the basal zone of the ice sheet. The main mechanism of basal motion was sliding and deformation of the subglacial sediments. Deformation probably occurred in restricted areas and did not have a pervasive character.

5

Relationships between microstructural features and mesoscopic fracture density in a Pleistocene till (Konin area, central Poland)

Włodarski Wojciech

Geologos

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2010

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Vol. 16, No. 1

3--26

EN

The qualitative and quantitative characteristics of microstructures in a till were analysed with SEM; it was also investigated whether the results depend on the till’s mesostructural characteristics. The till, exposed in a few open-cast browncoal mines near Konin in central Poland, is cut by numerous fractures which correspond to Riedel shear patterns, P-type structures and C-S type foliations. The fractures developed as a result of simple shearing induced by movement of the base of the Odranian ice sheet. On the basis of fracture density, two till types are distinguished: coarsely-brecciated till (wide spacing of fractures) and finely-brecciated till (closely spaced fractures). It is found that the fracture density is reflected in the microstructure of the till. The finely-brecciated till is characterised by a high porosity and has predominantly anisometric and fissure-like pores that also show a more clearly preferred orientation than the pores in the coarsely-brecciated till. In contrast, the coarsely-brecciated till has anisometric pores that show a less preferential orientation. The porosity of the coarsely-brecciated till is lower than in the finely-brecciated till. The finely-brecciated till probably represents a strongly deformed deposit, related in some cases to zones developed along thrusts that cut the till. Positive correlation between the porosity, the spatial arrangement of pores, and the density of fractures suggests a synsedimentary origin of the shear strain. This strain was accommodated by a particulate flow developed within both wide, pervasive zones and narrow, localised zones. The hydraulic conditions within the subglacial shear zone controlled rheological differences within the till during deformation and thus influenced the degree of the microstructure alteration.

6

Bio- and lithostratigraphical investigations of eemian fluviolacustrine sediments and tills from the lower Peene valley (Ne Germany)

Meng S., Börner A., Strahl J., Thieke H. U.

Polish Geological Institute Special Papers

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2009

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Vol. 25

37-48

EN

Corresponding biostratigraphical and lithological evidences permit to conclude that the drilled Eemian sediment was formed predominantly in fluviolacustrine facies in stagnant river lakes. The mollusc faunas investigated, therefore, is also of supra-regional significance and contains many mollusc species of the interglacial fluviolacustrine type. The stratigraphical classification of the sands as of the Eemian Interglacial age can be confirmed, finally, by the presence of Theodoxus fluviatilis. Moreover, the findings of Marstoniopsis scholzi were unknown so far from the Pleistocene in Germany. A constant pollen composition suggests a very short time of sedimentation during the Eemian namely from pollen zone 4 (cf. Erd, 1973) up to the beginning of pollen zone 5. The increasing rates of amphibole show an initial interglacial weathering impact. The surrounding morainic plateaus are covered only by a single Weichselian till (Mecklenburgian phase, qW3), which in the lower Peene valley directly overlays the Eemian fluvial deposits. A till of the younger Saalian (Warthian, qS2) underlays the fluviatile Eemian sands and the lowest till is classified as the lower Saalian glaciation (Drenthian, qS1). The Eemian fluvial sediments in the modern lower Peene valley argue for the existence of a pre-Weichselian river valley.

PL

Badania biostratygraficzne i litologiczne wykazały, że odwiercone osady interglacjału eemskiego powstały w jeziorze przepływowym występującym w dolinie rzecznej. Przeanalizowana fauna mięczaków ma znaczenie ponadregionalne i zawiera wiele gatunków charakterystycznych dla interglacjalnych warunków rzeczno-jeziornych. Na korelację piasków z interglacjałem eemskim wskazuje obecność gatunku Theodoxus fluviatilis. Stwierdzono obecność Marstoniopsis scholzi, który dotychczas nie był znany z osadów plejstoceńskich w Niemczech. Mało zróżnicowane spektrum pyłkowe dowodzi szybkiej sedymentacji w interglacjale eemskim podczas 4. i na początku 5. poziomu pyłkowego (por. Erd, 1973). Zwiększająca się zawartość amfibolu w osadach wskazuje na wietrzenie w pierwszej części interglacjału. Otaczająca wysoczyzna polodowcowa jest pokryta jednym pokładem gliny lodowcowej (faza meklemburska, qW3), która w dolnym odcinku doliny Peene bezpośrednio przykrywa eemskie osady rzeczne. Glina lodowcowa młodszego stadiału zlodowacenia Soławy (Warthian, qS2) podściela eemskie piaski rzeczne, natomiast niżej występująca glina lodowcowa została zakwalifikowana do starszego stadiału zlodowacenia Soławy (Drenthian, qS1). Eemskie osady rzeczne współczesnego dolnego odcinka doliny Peene wskazują na istnienie doliny rzecznej starszej od ostatniego zlodowacenia.

7

Till base deformation and fabric variation in Lower Rogowiec (Wartanian, younger Saalian) Till, Bełchatów outcrop, central Poland

Allen P., Krzyszkowski D.

Annales Societatis Geologorum Poloniae

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2008

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Vol. 78, No 1

19-35

EN

We documented that the Wartanian (younger Saalian) Lower Rogowiec Till exposed at Bełchatów, central Poland, is not sedimentologically or structurally homogeneous, and suggested that the till macrofabric patterns and deformation structures may be related to stress conditions in the glacier at the time of deposition. The distribution of deformation structures below and within the till forms a pattern, most probably associated with compressive flow and/or with stronger stress reaction, creating stronger fabrics, above clay beds due to high pore water pressure. The intervening areas, lacking deformation structures, occur between the zones of compression, where pressure would have been less. These patterns occur in a repeated sequence along the sections, which suggests that there may be a control, such as basal glacier stress conditions. The sites showing deformation occur about every 10–20 m. This could imply that the zones of shearing at the ice front have a similar spacing. There are no features in the pattern of the till macrofabrics and deformation structures to suggest that the local Kleszczów Graben or a pre-existing valley had any effect on the mode of till deposition.

8

Morfologia osadów podłoża zlodowacenia Wisły na obszarze polskiej części lobu Odry

Hermanowski P.

Przegląd Geologiczny

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2007

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Vol. 55, nr 2

133-133

9

The Pleistocene glacial deposits in the Bełchatów mine (central Poland): an exceptional rekord

van Loon A.J

Studia Quaternaria

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2006

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Vol. 23

3-9

EN

The Quaternary overburden of the giant Bełchatów browncoal mine has provided - and still provides - one of the world's best exposures of Pleistocene glacial sediments. The exceptional geological setting - a graben that has been active from the beginning of the Alpine orogeny - provides conditions for preservation of terrestrial glacial deposits that are unique. The well preserved glacial sediments can be studied in the walls of the mine providing more or less uninterrupted exposures for several kilometers, and the ongoing exploitation allows us to obtain a 3-D picture of the facies and facies transitions that have no counterpart elsewhere. These exceptional conditions have allowed identification of a glacigenic succession in which at least eight (but more probably 9 and possibly even more) glacial stratigraphic levels can be distinguished, thus recording an unmatched history of a glaciated area.

10

Zróżnicowanie petrograficzne i mineralne równowiekowych glinmorenowych z wybranych obszarów Niżu Polskiego

Kenig K.

Przegląd Geologiczny

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2004

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Vol. 52, nr 4

325-330

EN

Petrographic and mineralogical parameters of tills were studied in the region of Piła (NW Poland), Olsztyn (NE Poland) and Siedlce (E Poland). Lithostratigraphic zonation is introduced, based on values of petrographic coefficients. Petrographic parameters and heavy mineral com position of the tills differ between studied areas. Tills from the Piła region contain more resistant minerals (49.60–1.2%), then non-resistant ones (21.9–46.2), while similar characteristics are typical only for the lower strata in the Olsztyn area. Also the glauconite content var ies marekedly, from 0.6 % near Piła to 6 % near Olsztyn. The carbonate minerals are more abundant in the Olsztyn region (2.2–23.2%) than in the Piła area (1.3–7.1%). In all lithostratigraphic horizons of the Olsztyn region, the transparent minerals predomiate over the opaque minerals. This tendency is less obvious in the Piła region (except for two horizons). Lower and upper lithostratigraphic zones, equivalent to Pleistocene chronostratigraphic stages, were recognized in borecore sections from the study areas.