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Mafic and intermediate intrusions accompanying peraluminious granites of the Krušné hory Mts.batholit
Holečková, Pavla ; Jelínek, Emil (advisor) ; Ackerman, Lukáš (referee) ; Leichmann, Jaromír (referee)
Mafic and intermediate intrusions commonly accompany Variscan granitoid plutons in Europe. They are documented from different localities of Iberian Peninsula, from the French Massif Central, Schwarzwald, from different parts of the Bohemian Massif, in Romania, Greece, Corsica and Sardinia. They comprise wide petrographic varieties from quartz gabbros, diorites, granodiorites to monzonites. They usually constitute small bodies or veins, they often occur as mafic microgranular enclaves (MME) in granodiorites and in some granites. Dioritic intrusions are characterized by a relatively high amounts of lithophile elements (Rb, Sr, Ba, Cs, LREE), and they are simultaneously high in compatible elements (Ni, Cr, V a Co). Their isotopic ratios 87 Sr/86 Sr are in all compared locations similar and are close to the Bulk Earth (0.704 - 0.708). εNd values show larger scatter, some intrusions have more crustal composition (to -8), on the other hand, another intrusions have εNd positive, that points to a contribution of basic magma. The age of dioritic intrusions differs according to individual locality suggesting more than one magmatic episode. The oldest occur in the French Massif Central (361 - 365 Ma), whereas the youngest are documented in Iberia (312 - 310 Ma). The oldest mafic intrusions in the Bohemian...
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Study of the behavior of selected rocks at high temperatures
Holanec, Aleš ; Sitek,, Libor (referee) ; Bodnárová, Lenka (advisor)
The diploma thesis deals with the observation and diagnostics of transformations that take place in stone slabs of different mineralogical composition during heating to high temperatures. The theoretical part of the thesis deals with a summary of available information about selected types of rocks. Furthermore, it presents findings from the experimental thermal loading of a granite sample. The principles and instruments of laboratory experimental methods that are used to judge the resistance of rocks are described in detail. In the experimental part, the testing methodology is proposed, the procedure of production of rock test specimens is described and the way in which the thermal loading of stone slabs took place is explained. The results of the experiments are shown in the tables and graphs. A comparison of individual tests and properties of selected samples and evaluation of the obtained results is performed.
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Petrogenesis and emplacement of post-collisional granitoids of southeastern Moldanubian Batholith
Hájek, Tadeáš ; Verner, Kryštof (advisor) ; Houzar, Stanislav (referee)
The Weinsberg Composite Pluton, located in the southern part of the Moldanubian Batholith is a large intrusive body with complex internal fabrics, petrogenesis and emplacement processes. On the basis of geochemistry and zircon morphology classification the dominating lithology in the northeastern part of the pluton seems to be the second type of the Weinsberg granitoids (WbG II). Based on the integration of the structural, petrological and geochemical data set acquired from the investigated area, the interpretation of geodynamic evolution and emplacement of the eastern part of the Weinsberg Pluton could be proposed. This interpretation invokes: (a) indentation and underthrusting of a continental microplate (Brunia) in the east at around ~340-330 Ma, driving mantle delamination and subsequent heating and anatexis in the metapelitic lower crust as the heterogeneous source for Weinsberg- and Eisgarn-types of granitoids; (b) subsequent growth of a large metamorphic dome along the edge of the Brunia indentor followed by polyphase emplacement of entire eastern part of the Moldanubian Batholith around ~330-325 Ma including the Weinsberg Composite Pluton in the south; (c) increasing role of the N-S shortening and associated NW-SE dextral shearing along localized shear zones which caused the prevailing...
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Požáry granite and its properties influencing durability
Šťovíčková, Michaela ; Přikryl, Richard (advisor) ; Matějka, Dobroslav (referee)
Požáry Granite, cropping out on NW margin of Central Bohemian Plutonic complex, is ranked to the most valuable decorative varieties of natural stone in the Czech Republic. The stone is characterised by plausible appearance, excellent polishing ability and favourable physical properties. It has been used for numerous structures and monuments in the Czech Republic and abroad. Despite declared favourable properties, it is prone decay, specifically on the polished surface. This bachelor thesis discusses granite petrology, their weathering and usage for decorative purposes. In the second part, the thesis summarizes current knowledge on Požáry Granite. The study focuses on its position within the Central Bohemian Plutonic Complex, mineralogy, petrology, usage, and historical/current exploitation. This bachelor thesis is generally aimed as introduction to the planned master thesis which should focus on experimental study of Požáry Granite.
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Petrogenesis and emplacement of the Weinsberg granitoids in Nove Hrady Mts. (Moldanubian Batholith]
Hájek, Tadeáš ; Verner, Kryštof (advisor) ; Špillar, Václav (referee)
(english) First part of this bachelor thesis contains a summary of existing knowledge of post- collisional magmatic activity in Bohemian massif with accent on genesis and construction of large intrusive complex - Moldanubian Batholit. Possible geodynamical aspects, petrogenetical and physical processes of genesis and emplacement of granitic magmas are further described. Practical part of this bachelor thesis is based on observation and documentation of fabrics and structures in Weinsberg granitoids at rock outpost situated in locality Sokolčí u Kaplice.
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Springs of the radioactive mineral waters on Tanvald granite
Kohn, Pavel ; Goliáš, Viktor (advisor) ; Vylita, Tomáš (referee)
In the years 2014-2015 a radiohydrogeochemical survey was carried out in the Tanvald granite body. Tanvald granite is a two-mica granite body located on the southern edge of the Krkonoše-Jizera Pluton, in the Lusatian part of the Saxony and Thuringian zone of the Variscan orogenic belt. The aim of the survey was to find radioactive water, the 222 Rn volume activity of which exceeds 1500 Bq/l. Such water is - under the Act no. 164/2001 Coll. - considered as radioactive mineral water. The result was a found of 20 water sources meeting this condition and many other sources approaching this value. In terms of the findings, the most important area is Dlouhý Most, where 8 of the radioactive water resources exceeding 1500 Bq/l were found. The most important of these is probably the source TGR/11 with the 222 Rn volume activity 2449 Bq/l. A cluster of water sources with a slightly higher conductivity (exceeding 300 µS/cm) appears in the Dlouhý Most area. Chemical analysis of the most important of them (TG1/15) showed that it is water of the Na-Ca-Cl type, probably contaminated by a run-off from the motorway, which is salted in winter. Another important site is the Kokonín fault area. At this important geological structure a total of four springs of radioactive water with the 222 Rn volume activity greater...
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Structural and Petrophysical Characterisation of Granite Intended for Radioactive Waste Stocking
Staněk, Martin ; Lexa, Ondrej (advisor) ; Žák, Jiří (referee) ; David, Christian (referee)
Structural and petrophysical analysis have been conducted within the Melechov massif with focus on structures controlling the porosity, permeability and thermal conductivity of the rock. The structure of the massif has been constrained based on extensive dataset including AMS and field structural measurements of ductile and brittle structures. Maps and stereograms have been constructed to display the magnetic fabrics and the fracture system of the studied massif. The fracture system of the massif has been described by two principal and two supplementary sets of joints and by faults formed mainly by joint reactivation or less frequently formed as shear fractures. The measured petrophysical data have been used to characterize the effect of fracturing and alteration on pore space geometry and in turn on permeability, thermal conductivity and elastic properties of the studied granite. Distinct petrophysical properties have been identified for pristine granite, for fractured fresh granite as well as for fractured granite altered by Fe-oxide, chlorite and clay minerals. Relations between the measured petrophysical properties have been explained in terms of evolution of the rock pore space. A detailed microstructural study combined with multidirectional P-wave velocity measurements at high confining pressure and...
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Diamond wheels and their use in the stone industry
Skryja, Jan ; Kolář, Ladislav (referee) ; Jaroš, Aleš (advisor)
This bachelor thesis deals with stone sawing during stone processing. It is divided into theoretical and practical parts. In the theoretical part diamond blades, the sawing process and stone extraction are described. The practical part is focused on the wear of circular saws in granite circular sawing. The wear is determined for two diamond cutting blades made by different manufacturers and is determined by the blade weight loss and segments height loss as a function of time. Both measured values show linear dependence. The results are the basis for a future comparison of the two diamond blades on the economic side, which is not the subject of this work.
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