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Petrografická identifikace vulkanické horniny z vrchu Větrovec u Vysoké Lípy v NP České Švýcarsko
Adamovič, Jiří ; Mészárosová, Noemi ; Mikysek, Petr
Byla provedena petrografická analýza dvou vzorků vulkanitů odebraných z intruze v pískovcích jizerského souvrství na jihozápadním svahu vrchu Větrovec, kat. Vysoká Lípa. Pomocí optické mikroskopie, fázové analýzy metodou práškové rentgenové difrakce a bodových kvalitativních analýz jednotlivých minerálních fází na elekronovém mikroskopu s EDS detektorem byly popsány jednotlivé minerální fáze v obou vzorcích a zjištěny jejich obsahy a vzájemné vztahy. Hornina vzorku 1 je rhönitický olivinický bazalt s možnými přechody do rhönitického nefelinického bazanitu, hornina vzorku 3 je vesikulární rhönitický olivinický bazalt.
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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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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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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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