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Radioactivity of granitoids of the Krkonoše-Jizera pluton
Černík, Tomáš ; Goliáš, Viktor (advisor) ; Matolín, Milan (referee)
2. SUMMARY This thesis is focused on the natural radioactivity of the Krkonoše pluton, which is divided in 6 particular types of granite: the Jizera, the Liberec, the Fojtka, the Tanvald, the Harrachov, the Krkonoše ones. The goal of the thesis was to compare these values and find out whether there was an unlike element (U, Th, K) content difference. Based on literature data about the Czech and Polish part of pluton, there was assigned data of the analysed samples (of contents of K, U, Th) to each type of granite. The literature data was refined on the base of the current knowledge. The localized collection points were assigned to the particular types of the Krkonoše - Jizera granitoids. The analytic data collection was statistically evaluated. On the base of the statistic data evaluation significant differences of the radioactive element content of the particular types of granite was proved. The most radioactive one is the Harrachov granite. The Tanvald one has a distinctively anomalous ratio of U to Th higher than 1. The other types of granite have only an average level of radioactivity. There was also checked a significant aerial gamaspectrometric anomaly in the south - west direction of Hejnice. There was made a field gamaspectrometric measurement, which did not prove the significant increase in an...
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Adsorption of radionuclides in granite pores and micropores
Šindelář, Jakub ; Mls, Jiří (advisor) ; Šantrůček, Jaromír (referee)
Adsorption of radionuclides in granite pores and micropores ABSTRACT This graduation thesis deals with laboratory determination of adsorption isotherms parameters. Granite from the central moldanubian pluton, site Panské Dubenky, Czech Republic, was chosen to the experiment. The place is one of the candidate sites to build a deep nuclear waste disposal. A batch experiment was performed in two modes, differing in the way of addition of radioactive nuclide 90 Sr. From this experiment, distribution coefficients for a linear isotherm or parameters for Langmuir isotherm were obtained. Beside this, a through-diffusion experiment was performed. The objective of this experiment was to identify whether some of the radionuclides used (137 Cs, 90 Sr, 125 I) is able to penetrate through the pores of a granite slice barrier between two solutions of different concentrations. During the period of the experiment no radionuclide was detected reliably.
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Geodynamic evolution and emplacement of Eisgarn - type granitoids (Moldanubian Batholith)
Paclíková, Jana ; Verner, Kryštof (advisor) ; Franěk, Jan (referee)
English abstract This diploma thesis deals mainly with identification of magmatic (respectively magnetic) fabrics, geodynamical aspects of emplacement and geochronology of the Eisgarn granitoids. For the analysis Klenov and Mrákotín pluton were chosen, which is placed in the eastern part of the Moldanubian Batholith. This thesis contains petrological and mezoscopic structural analysis of the host metamorphic rocks of the Moldanubian Unit and it includes calculation of P-T conditions of the main mineral assemblage. This is followed by petrological, geochemical and mezoscopic structural analysis of the Klenov and Mrákotín pluton and analysis of the anisotropy of magnetic susceptibility, geochronology of the Klenov pluton, gravimetry analysis and determination of the orientation of density interfaces in different depths. Granitoids of the Klenov and Mrákotín pluton are characterized as S-type granitoids, whose protolith were probably metasedimentary rocks. From the analysis it is also evident that the Klenov pluton records lower degree of magma fractionation than the Mrákotín pluton. The emplacement and crystallization of both studied magmatic bodies took place in cooperation with a development of regional metamorphic fabrics, which originate between 329 and 327 Ma. During this period a rapid exhumation of...
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Numerical model for the origin of magmatic textures and its application to the Fichtelgebirge/Smrčiny granite batholith
Špillar, Václav ; Dolejš, David (advisor) ; Ježek, Josef (referee) ; Žák, Jiří (referee)
Magmatic processes are major agents responsible for the formation and differentiation of the Earth's crust. In contrast to extensive efforts to improve understanding and utility of igneous geochemistry, physical processes of magma differentiation and solidification remain largely unclear. Large variability of igneous textures provides record of these processes and intensive parameters governing the crystallization. In this thesis, we develop quantitative methods, which allow us to better interpret igneous textures in the framework of physics of solidification. We have developed a new three-dimensional model of crystallization from one- component melt driven by homogeneous and heterogeneous nucleation and crystal growth. The predicted textures are quantitatively characterized by crystal size distributions, spatial distribution functions and parameters representing grain contact relationships. The model employs high resolution in a large volume simulation domain in order to produce statistically stable results. Our simulations, performed for various functional forms of nucleation and growth rates with respect to time, imply that (i) crystals are ordered (anti-clustered) on short length scales. This reflects that other crystals already have a finite size at the time of nucleation of younger crystal,...
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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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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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