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Number of results: 6
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Abstract

Textural properties and microstructures are commonly used properties in the analysis of Pleistocene and older glacial deposits. However, contemporary glacial deposits are seldom studied, particularly in the context of post-depositional changes. This paper presents the results of a micromorphological study of recently deposited tills in the marginal zones of Hansbreen and Torellbreen, glaciers in southwestern Spitsbergen. The main objectives of this study were to compare modern tills deposited in subglacial and supraglacial conditions, as well as tills that were freshly released from ice with those laid down several decades ago. The investigated tills are primarily composed of large clasts of metamorphic rocks and represent coarse-grained, matrix-supported diamictons. The tills reveal several characteristic features for ductile (e.g. turbate structures) and brittle (e.g. lineations, microshears) deformations, which have been considered to be indicative of subglacial conditions. In supraglacial tills, the same structures are common as in the subglacial deposits, which points to the preservation of the primary features, though the sediment was transferred up to the glacier surface due to basal ice layer deformation and redeposited as slumps, or to formation of similar structures due to short-distance sediment re-deposition by mass flows. This study revealed that it might not be possible to distinguish subglacial and supraglacial tills on the basis of micromorphology if the latter are derived from a subglacial position. The only noted difference was the presence of iron oxide cementation zones and carbonate dissolution features in supraglacial tills. These features were found in tills that were deposited at least a few years ago and are interpreted to be induced by early post-depositional processes involving porewater/sediment interactions.
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Authors and Affiliations

Grzegorz Rachlewicz
Katarzyna Skolasińska
Witold Szczuciński
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Abstract

The article presents the results of CRL research on glacial till contaminated with JET A1 aviation fuel and mineral oil 15W40. The conducted research has shown that the compressibility of fine grained soils contaminated with hydrocarbons during a constant rate of loading tests depends on the physical properties of the soil, properties of oil contaminants, their content in the soil pores as well as the adopted loading velocity. The implemented laboratory test program shows that the contamination of glacial till with hydrocarbons increases their compressibility. Moreover, this research shows that the CRL test method may be recommended in the compressibility research of fine grained soils contaminated with hydrocarbons.
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Authors and Affiliations

Piotr Stajszczak
1

  1. Geoteko Geotechnical Consultants Ltd., ul. Wałbrzyska 14/16, 02-739 Warszawa, Poland
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Abstract

The Quaternary overburden of the giant Belchatów 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. Outcrops in Pleistocene glaciation-related sediments are commonly small, but the well preserved glacial sediments in the Belchatów mine can be studied without significant interruptions in the walls for several kilometers. In addition, the ongoing exploitation provides an opportunity to obtain a 3-D picture of the faciès and facies transitions that have no counterpart elsewhere. The stratigraphie relationships between a large number of glacial and interglacial units, some of which have a limited lateral extent, could thus be unraveled. It appears that the glacigenic succession comprises at least eight (but probably more) stratigraphie levels with glacial diamictons, thus recording an unmatched history of a glaciated area.
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Authors and Affiliations

Antonius J. (Tom) van Loon
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Abstract

The site at Orłowo Cliff was used to analyse the stratigraphic position and palaeogeographic interpretations of the properties and depositional conditions of two basal tills from the Late Pleistocene. A multi-proxy approach involved lithofacies, petrographic analysis of the fine gravel fraction, analyses of indicator erratics and till fabric. TL dating of intra-moraine deposits was used to determine depositional time frames of tills. The sediment profile at Orłowo Cliff shows a distinct reduction in number of Pleistocene units. Obtained dating results suggest the presence of Middle and Late Pleistocene fluvial units. The main issue discussed is the stratigraphic position of the older till (Unit O-4). It can be assumed that this till was deposited probably during the Middle Weichselian (MIS4). At Orłowo Horn the till of Unit O-4 reveals incorporation of the erratic material derived from an older till in the surrounded area (according to petrographic composition – probably from MIS 8). The younger till (Unit O-6) was deposited in the Late Weichselian (MIS 2). Moreover, the till of Unit O-6 is characterised by a significant shift towards the south-west in terms of the erratic origin in Unit O-4.
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Authors and Affiliations

Piotr Paweł Woźniak
Robert J. Sokołowski
Piotr Czubla
Stanisław Fedorowicz
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Abstract

Arid areas are particularly susceptible to soil erosion due to long dry periods and sudden heavy downpours. This study investigates the aggregate size distribution and aggregate stability of twelve tilled fallow areas of Hyderabad district, Sindh, Pakistan. This study determined aggregate size distribution by dry sieving to evaluate the seedbed condition and aggregate stability using wet sieving to assess the susceptibility of tilled fallow areas to soil erosion. The aggregate size distribution of the soils of the selected areas was highly variable. Gulistan-e-Sarmast had the largest number of clods (51.0%) followed by Kohsar (49.0%), Latifabad # 10 (41.10%) and Daman-e-Kohsar (39.0%). Fazal Sun City, the left side of the Indus River, the Village Nooral Detha and the left side of the Abdullah Sports city had a greater number of large (>8.0 mm) and small aggregates (<0.5 mm). The optimum aggregate size distribution was found in the left side of the channel, which had the largest number of aggregates (50.50%) in the 0.5–8.0 mm sieve size range. Maximum aggregate stability (AS) was found in Gulistan-e-Sarmast (46%), Kohsar (42%) and Latifabad # 10 (34%), while all other soils had minimum aggregate stability (<14%). The minimum aggregate stabilities demonstrate that the tilled fallow areas of Hyderabad district are highly susceptible to erosion. Therefore, the present study suggests investigating potential ways to enhance the aggregate stabilities of soils.

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Authors and Affiliations

Ahmed Tagar
Jan Adamowski
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Abstract

This article examines the history of periodicals which have been published in Sandomierz, or had an ongoing interest in the town, since 1816, when the first publication of this kind went into print. Apart from the Polish segment, the article covers periodicals in Latin, German, English, Russian and Dutch. So far c. 230 items on wide range of themes have been sourced to Sandomierz.
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Authors and Affiliations

Izabela Krasińska
1
ORCID: ORCID

  1. Uniwersytet Jana Kochanowskiego w Kielcach Instytut Mediów, Dziennikarstwa i Komunikacji Społecznej ul. Uniwersytecka 17 PL 25-406 Kielce

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