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Substitution trends in apatites of Cenozoic igneous rocks of the Czech Republic
Mészárosová, Noemi ; Skála, Roman (advisor) ; Ulrych, Jaromír (referee)
This bachelor thesis is focused on studying crystal chemistry of apatites of the Cenozoic igneous rocks of the Czech Republic. The main goal of this thesis is to determine the substitution trends in 23 samples of apatites from selected volcanic rocks of České středohoří Mts., Doupovské hory Mts. and the Labe Tectono-volcanic Zone. It was found that contents of REE (Ce, La, Bd, Sm, as well as Y) and Si correlate mutually. In addition to that this group of elements displays the inverse correlation with Ca and P. These observations confirm the coupled substitution of REE, Y and Si. The second part deals with refinement of crystal structures of studied apatites. The crystal structure of selected samples was refined by Rietveld method. All samples displayed different peak shapes for 00l reflections compared to other reflections. It can be assumed that the change of the shape parameters was caused by different size of crystallites in this direction. During the refinement it was found that the samples A7 and A10 contain two different apatites displaying very similar crystal lattice parameters. In the sample A7 this fact is caused by chemical zoning, in particular, by different concentrations of Ce and La.
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Distribution of trace elements in carbonatites using in-situ techniques, with focus on REE
Krátký, Ondřej ; Magna, Tomáš (advisor) ; Kynický, Jindřich (referee)
Carbonatites are unique and enigmatic magmatic rocks of unclear origin, with very specific mineralogy and geochemical properties. They are predominantly composed of magmatic calcite or other carbonate minerals (Le Bas 1987) and have low content of SiO2 (Le Maitre 2002). Origin of these peculiar magmas is still not clear but they appear to represent an important "window" into processes in Earth's mantle. They are considered either as residual melts from a fractionated carbonated nephelinite or melilitite (Gittins 1989; Gittins and Jago 1998), as immiscible fractions of CO2-saturated silicate melts (Freestone and Hamilton 1980; Amundsen 1987; Kjarsgaard and Hamilton 1988, 1989; Brooker and Hamilton 1990; Kjarsgaard and Peterson 1991; Church and Jones 1995; Lee and Wyllie 1997; Dawson 1998; Halama et al. 2005; Brooker and Kjarsgaard 2011), or as primary melts which are were generated from CO2-bearing peridotite through partial melting (Wallace and Green 1988; Sweeney 1994; Harmer and Gittins 1998; Harmer et al. 1998; Ying et al. 2004). Abundances of rare earth elements (REE) are often high in carbonatites because carbonatitic magmas can dissolve these elements much easily than silicate magmas (Nelson et al. 1988). Carbonatitic magma can also dissolve large quantities of Sr, Ba, P and mainly Zr and Nb,...
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Additional components of feldspar deposit of Krásno Krásno - Vysoký Kámen: composition and relation to the feldspar material
Vrbický, Tomáš ; Přikryl, Richard (advisor) ; Štemprok, Miroslav (referee)
The Krasno deposit is only one active mine at Slavkovsky les. Mined are feldspars raw materials with high quality, commonly used in ceramic and glass industry. Mined raw material has a lot of additional components, which has influence on quality of raw material. Main additional components are unwanted coloring Fe oxides. Another additional components are apatite and topaz, which dont have influence on quality of raw material. The most interesting additional components of raw material are Ta - Nb, Li - Rb minerals. Currently the processing of raw material is under modernization for maximal separation high quality of feldspar material. The result of semi-processing operation shows the concentrate can be potential source of strategic raw materials as Nb - Ta or Li - Rb mineralization. For separation of these minerals and elements must be realized detailed research of selected processing and properties of these minerals. Powered by TCPDF (www.tcpdf.org)
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Variability of chemical composition of apatites from alkaline rocks of the Bohemian Massif
Mészárosová, Noemi ; Skála, Roman (advisor) ; Filippi, Michal (referee)
III Summary This thesis is focused on crystal chemistry and crystal structure of apatites from alkaline rock of the Bohemian Massif. Fifteen samples of volcanic rocks, mostly of the Cenozoic age was selected for the study. Sample No. 5 is of the Silurian age. Sample No. 15 originates from volcanic rock of the Cenozoic age from the Slovak Western Carpathians. This sample was chosen for this study due to its substantially different chemical composition. The contents of major and minor elements in apatites were measured on an electron microprobe, the contents of some minor and trace elements were determined by laser ablation inductively coupled plasma mass spectrometry. Selected samples were investigated by cathodoluminescence (CL) spectrometry. Crystal structure of studied apatites was characterized by X-ray diffraction and Raman spectroscopy. It was found that dominant anion at position X is fluorine. The OH content calculated on the basis of the fully occupied position X is significant in some samples. The amount of Cl is generally low. The exception is the sample No. 15 where Cl reached up to 0.6 apfu (Z = 2). Studied apatites contain many substitutions but they are generally of minor extent. Strontium, iron and REE at position M belong to the most common and most important substituents for calcium in...
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Determination of geological provenance by cathodoluminescence spectroscopy of apatites and carbonates
Pánik, Róbert ; Matějka, Dobroslav (advisor) ; Ježek, Josef (referee) ; Skála, Roman (referee)
This work presents new method for determination of geological provenance based on the statistical analysis of cathodoluminescence spectra of marbles and carbonate rocks from various localities in the Bohemian Massif. Analysis is based on the combination of data from seven different measures of spectral similarity and provides results that are more robust than those obtained by approach based only on a single measure of similarity. These results may be further improved by employing meta-analysis that evaluates behaviour of spectra during the individual steps of analysis. Analysis was performed on the original cathodoluminescence spectra, as well as on the residual spectra in which relative variability was amplified by the subtraction of Gaussian trend present in all spectra of carbonates. By combining results from analysis and meta-analysis of both original and residual spectra it was possible to almost unambiguously determine provenance of samples from all studied localities. Agglomerative hierarchical clustering was employed as a supplementary method for classification of spectra. Out of 72 different methods for clustering, one was selected for both original and residual data based on the number of correctly classified spectra. Second part of this work presents analysis of cathodoluminescence...
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Substitution trends in apatites of Cenozoic igneous rocks of the Czech Republic
Mészárosová, Noemi ; Skála, Roman (advisor) ; Ulrych, Jaromír (referee)
This bachelor thesis is focused on studying crystal chemistry of apatites of the Cenozoic igneous rocks of the Czech Republic. The main goal of this thesis is to determine the substitution trends in 23 samples of apatites from selected volcanic rocks of České středohoří Mts., Doupovské hory Mts. and the Labe Tectono-volcanic Zone. It was found that contents of REE (Ce, La, Bd, Sm, as well as Y) and Si correlate mutually. In addition to that this group of elements displays the inverse correlation with Ca and P. These observations confirm the coupled substitution of REE, Y and Si. The second part deals with refinement of crystal structures of studied apatites. The crystal structure of selected samples was refined by Rietveld method. All samples displayed different peak shapes for 00l reflections compared to other reflections. It can be assumed that the change of the shape parameters was caused by different size of crystallites in this direction. During the refinement it was found that the samples A7 and A10 contain two different apatites displaying very similar crystal lattice parameters. In the sample A7 this fact is caused by chemical zoning, in particular, by different concentrations of Ce and La.
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