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1

Effect of soil management on its radioisotopic composition

Dołhańczuk-Śródka A., Ziembik Z., Kusza G.

Geology, Geophysics and Environment

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2015

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Vol. 41, no. 1

33--41

EN

Radioactive isotopes in the environment, both natural and artificial, can be good indicators in the analysis of a number of physical and chemical processes and the transport of pollutants in the ecosystem. The main aim of this study was to evaluate the impact of soil use on the radioisotopic composition in its surface layers. The radioisotopic compositions of surface soil samples, collected in the area of a cement plant, abandoned for over 20 years, as well as in the area of the nearby allotments were examined and compared. Calculations were performed using methods designed to study compositional variables. The results confirmed a significant impact of the way soil is used on the radioisotopic composition of the surface soil layers. However, some characteristics of the composition were common to both locations. It was discovered, that a significant proportion of the lead isotope Pb-210 was derived from atmospheric deposition. Other radioisotopes remained relatively close to equilibrium in their decay chains.

2

Metoda biplot w interpretacji danych złożonych (CDA) w geologii

Labus K., Labus M.

Przegląd Geologiczny

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2010

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Vol. 58, nr 5

436-442

EN

Compositional data consist of compositions of parts summing to some whole (e.g.: 100%, 1). Such "closed" data are very popular in geochemistry, sedimentology, hydrogeology and environmetrics. This paper presents the data visualization method by means of the biplot method - a statistical technique widely applied in Compositional Data Analysis. This method enables a graphical display of observations and variables on the same chart, in a way that approximates their correlation. In a biplot the observations are marked with points, and variables - by rays emanating from the origin. Both their lengths and directions are important to the interpretation. The paper presents two examples of implementation of biplots in analysis of hydrogeological and petrological data. The first example concerns petrological data set for pores and skeleton grains of different Polish sandstones. The biplot visualization unveiled a possible independence of subcompositions of transitional pores (T) and macropores (R), as well as submacropores (S) and skeleton grains (Re). The use of this method made it also possible to demonstrate the rule according to which the share of transitive pores decreases at the advantage of real macropores from younger to older rocks, what is related to diagenesis processes. The second example concerns interpretation of hydrological data on chemistry of mine water of the "Rydułtowy" coal mine. In this case the graphical interpretation of biplot revealed large relative variation between HCO3 –-Cl–, HCO3–-I – and HCO3–-Na+. Besides, on the same basis, possible independence between the ion couples: HCO3--Br–, Ca2+-Na+, HCO3–-Cl–, Br-Na+, HCO3–-Cl–and Ca2+-K+ was identified and consequently verified using statistical tests. Additionally, taking into account geometrical features of the relevant biplot, a formula was proposed for defining relationships between shares of ions: Ca2+, Mg2+, Na+ and Cl–<.sup>, SO42–, HCO>sub>3–. These relationships are most apparent for poly-ion groundwater of the active exchange zone, where the ratios of the above mentioned components are similar to each other, despite a slight predominance of SO42– and HCO3– fractions.

3

Zastosowanie analizy danych złożonych (CDA) w geologii

Labus K., Labus M.

Gospodarka Surowcami Mineralnymi

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2006

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T. 22, z. 2

39-52

PL

W artykule przedstawiono podstawowe założenia metody danych złożonych - Compositional Data Analysis. Metoda ta pozwala na statystyczną interpretację danych, w których wartości zmiennych sumują się do pewnej całości. Pokazano przykłady zastosowania metody CDA dla danych hydrogeologicznych oraz petrologicznych - w tym interpretację tych danych i ich wizualizację za pomocą diagramów trójkątnych. Specyfiką metody jest możliwość stosowania szeregu procedur przekształceń, np. amalgamacji danych, perturbacji, uwalniania i centrowania.

EN

The paper presents the principles of Compositional Data Analysis. This statistical method enables interpreting the data, being proportions of some whole. The two examples of implementation of this method were presented, with use of hydrogeological and petrographical data. The visaulisation by means of ternary diagrams is helpful for interpreting the results. The method is particularly featured by the possibility of appllication of a range of helpful manipulations, such as: amalgamation, perturbation, unconstraining and centering of data.

4

Compositional Data Analysis as a tool for interpretation of rock porosity parameters

Labus M.

Geological Quarterly

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2005

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Vol. 49, No. 3

347-354

EN

This work examines the possibility of implementing the statistical method, Compositional Data Analysis (CDA), to rock porosity measurement data. The rock samples analysed are different types of sandstones from Poland. Porosimetricmeasurements were carried out using the mercury injection capillary pressure method, together with computer image analysis. In this paper, compositions of data concerning pore distributions are analysed. Rock pores were distributed in 4 classes of pore dimensions: transitive pores, submacropores, realmacropores and over-capillary pores. Based on the CDAmethods it was revealed that: there is no constant proportion between transitive andmacropores in the sandstones analyzed; the variability of the realmacropores, over-capillary and transitive pores and the skeletal grains fraction is mainly one-dimensional. The relative variation between transitive pores and real macropores determines the variability in the sandstone stratigraphical groups; however, these groups are not very distinct as regards the pore sizes and skeletal grains proportion. The rock parameters: median pore diameter; threshold pore diameter and total pore area might be used as independent variables in equations that explain reasonable parts of variability of pore sizes and skeletal grains fraction log-ratios.