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Fabrics of the Weinsberg granitoids on example of the Prášily pluton (Moldanubický plutonický komplex)
Pour, Ondřej ; Verner, Kryštof (advisor) ; Racek, Martin (referee)
This bachelor thesis is concerned with the brief introduction to the structures and fabrics in granitoid plutons. In the next part of this work are sumarized results of structural analyses of Weinsberg-type granite intrusion (Prášily pluton) located in the SW part of high-grade rocks of the Moldanubian Zone. This research proceeded based on a combination of field structural data and results of AMS (Anisotropy of magnetic susceptibility) method. The internal fabrics and structures of the Prášily pluton reflect emplacement mechanisms, kinematic history and evolution of the regional strain field during Variscan orogeny at around 330 Ma. The examined area provides crucial constraints for the geodynamic models of geological evolution of deeper parts of the Variscan orogen in the SW part of the Bohemian Massif.
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Emplacement and magnetic fabrics in dikes of syenite porphyries (Western Moldanubian Zone)
Orságová, Lucie ; Verner, Kryštof (advisor) ; Žák, Jiří (referee)
ENGLISH ABSTRACT We present new results of structural and magnetic (AMS) analyses of selected dikes of melasyenite, quartz melasyenite to melagranite porphyries accompanied by lamprophyres (minettes). The studied dike from the locality Nihošovice were dated by U-Pb method on zircons at 338 Ma. The asymmetric structural pattern of the studied dikes gives an excellent evidence for their emplacement and orientation of magmatic flow. The studied dikes were emplaced into: (i) Prevailing parts of the Central Bohemian Plutonic Complex (locality Malčice) and (ii) host high-grade metamorphic rocks of western part of the Moldanubian Zone (locality Nihošovice). Despite of the extensive area of occurrence, compositional variations and age of emplacement of these dikes are relatively narrow. Their geochemical and petrological compositions broadly correspond to ultrapotassic plutonic rocks (durbachites). The dikes are steeply dipping in trend ~NNW-SSE to ~W-E, with range in width between ~20 and ~25 meters. In general, our results show: (i) A relatively low degree of magnetic anisotropy (P= 1.012 - 1.152); (ii) Mostly oblate (planar) fabric, especially in marginal parts of the intrusive bodies (T= -0.091 - 0.941); (iii) Evidence for subhorizontal magmatic flow trajectory defined for a newtonian magma with typical...
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GEOMORPHOLOGY OF VELKÝ AND MALÝ BLANÍK
Bártová, Jitka ; Votýpka, Jan (advisor) ; Verner, Kryštof (referee)
Thie thesis consists of three main parts: an introduction, a description of physical conditions in the studied area and a main part which includes results of geomorphologic research and mapping. The area of interest is situated in central Bohemia in preserved area called Blanik. In the region there are two structural hills where the research was done. The names of these hills are Velký and Malý Blaník. Geologic structure of the region is built of Proterozoic - Paleozoic metamorphic rocks of Moldanubicum. Moldanubicum is represented here by muscovite - biotite orthogneiss (called blanicka ) and muscovite - biotite paragneiss. Both hills are created by muscovite - biotite orthogneiss so all the landforms are of its origin. There were classified structural, cryogenic, fluvial and other landforms in this thesis. Special attention was paid to cryogenic forms: frost - riven cliffs, cryoplanation plateaux, pseudocirques, block fields and many others. Almost 1000 measurements of joints were done. Cloose` s rosettes show systems of joints which prove tectonic system in the region and determine different mezoforms. Mapping brought some more results. Fluvial erosional and accumulative forms were classified as well as the anthropogenous forms. Powered by TCPDF (www.tcpdf.org)
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Komplexní geologická charakterizace prostorů PVP Bukov
Verner, K. ; Bukovská, Z. ; Souček, Kamil ; Vavro, Martin ; Staš, Lubomír ; Kaláb, Zdeněk ; Havlová, V. ; Kučera, P.
This report summarizes results of ongoing basic and applied research related to the project "Comprehensive geological characterization of underground research facility (PVP) Bukov" (PB-2014-ZL-U2301-004-BUKOV). In the wider area of the PVP Bukov a steep NW-SE trending metamorphic foliation was identified which is partly refolded into sub-horizontal direction. Faults and extensional joints with variable mineralization are mostly steep, trending mostly NW - SE or NNE - SSW. In addition, geological map at the scale of 1 : 4 500 of this area has been processed based on new field geological mapping and archival data. Moreover, a detailed petrographic and structural analysis of boreholes S-1 to S-4 (a total length of 470 meters) has been made. On the basis of U/Pb dating the age of the protolith of prevailing migmatized amphibolic gneisses was determined at 500-600 Ma as well as the subsequent regional metamorphism associated with partial melting and deformation at around 338 Ma. Results of thermodynamic modeling revealed the P-T conditions of regional metamorphism at T: 692–727 °C and P: 5 kbar.
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