Wyniki wyszukiwania - BazTech

1

Evaluation of compressibility of glacial till contaminated with hydrocarbons on the basis of CRL tests results

Stajszczak Piotr

Acta Geologica Polonica

|

2023

|

Vol. 73, no. 2

247--262

EN

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.

2

Zmiany właściwości konsolidacyjnych, filtracyjnych i mikrostrukturalnych glin lodowcowych w przebiegu badań konsolidacji z ciągłym wzrostem obciążenia

Stajszczak Piotr, Dobak Paweł, Gendek Katarzyna

Przegląd Geologiczny

|

2020

|

Vol. 68, nr 11

843--852

EN

The article presents results of CRL (Constant Rate of Loading) tests obtained for glacial till from the Warsaw region (Fort Służew). The analyses show that the significantfactors affecting the course of the consolidation with continuous loading (CL) of tested soils are related to the degree of water saturation of pore space, the state of soil structure, and the rate of loading. Values of filtration and consolidation parameters documented during CRL tests are dependent on the structural history and properties of soils. Before and after CRL tests, microstructure of till was studied by SEM methods. Changes in the pore space parameters in matrix microstructure, evaluated from CRL tests, are marked in different consolidation behaviours of tested natural and remould till.

3

Zastosowanie ziemskich izotopów kosmogenicznych w datowaniu glin lodowcowych : potencjał, ograniczenia i perspektywy badawcze

Tylmann Karol, Moskalewicz Damian

Przegląd Geologiczny

|

2020

|

Vol. 68, nr 10

764--773

EN

Determination of numerical age for glacial till is one of the most intriguing issues in glacial geology and geomorphology. Till layers are unequivocal evidence of ice sheets advances and retreats, and therefore they are very important for Quaternary palaeoclimatic reconstructions. Herein, we present a review dedicated to the methodology of glacial till dating with in situ cosmogenic nuclides. This relatively novel approach enables direct dating of deposition of till and its exposure after deglaciation. Getting reliable numerical age (in years) of till opens a new prospect for reconstructions of past glaciations and palaeogeographic studies. Despite some limitations of applying in situ cosmogenic exposure and burial dating, we argue that this technique may be successfully employed in studies of glacial deposits in Poland.

4

Zastosowanie mikrotomografii komputerowej do badania orientacji klastów w glinach lodowcowych

Hermanowski Piotr, Duda Piotr

Przegląd Geologiczny

|

2019

|

Vol. 67, nr 8

653--661

EN

Limitations of macroscopic measurements and observations of glacial tills, no matter how informative they are, have contributed to the development of micromorphological analysis first in thin sections, since the 80’s using X-ray computed tomography, and recently X-ray computed microtomography (μ-CT). The цCT has found wide applications in science including earth sciences where is used for imagining various geological samples in the 3D view. The sampling procedure and preparation of samples do not generate much effort, and eventually, allow analysis of samples with a preserved undisturbed structure. Herein, we present a short review and methodology of μCT as well as its application to the study of glacial tills. For example, we analyzed a subglacial till sample from the lee side of a drumlin located in the Stargard drumlin field area, NW Poland. The results show a distinctive bimodal pattern of clast fabrics which is interpreted as a result of subglacial till squeezing. Smaller clasts are obliquely oriented to the major direction of the ice flow whereas the larger clasts orientation is approximately in accordance with the major shear stress direction. Overall, our data emphasize the potential of the μ-CT in glacial till studies.