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Pre-Variscan tectonometamorphic evolution of Zábřeh crystalline unit and its geotectonic position
Jůzlová, Klára ; Lexa, Ondrej (advisor) ; Buriánek, David (referee)
This thesis is focused on the study of the evolution of the Zábřeh crystalline unit on the eastern margin of the Bohemian Massif. The main focus is U-Pb dating of detrital zircons obtained from metasediments of the zábřeh series and dating of magmatic zircons from metamorphosed rocks in the vicinity of the village Hynčina. The data are supported by structural analysis, petrographic descriptions and geochemical analyses of rocks. The thesis aims to determine the age of sedimentation and protoliths and thus clarify the interrelationship of the subunits forming the Zábřeh crystalline unit. The results of the thesis indicate that the Zábřeh crystalline unit represents a segment of cambro- ordovician rift zone developed along northern margin of Gondwana affected by early Variscan metamorphism likely related to mid-Devonian back-arc extension. Keywords: Zábřeh crystalline unit, Eastern margin of Bohemian Massif, pre-variscan tektonometamorphic evolution, U-Pb zircon dating
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Magnetic fabrics and emplacement of the Eisgarn granitoids (Moldanubian Plutonic Complex)
Paclíková, Jana ; Verner, Kryštof (advisor) ; Buriánek, David (referee)
English abstract We consider our preliminary results of structural and AMS analyses of granitoids of the Mrákotín and Klenov Plutons located in the northeastern part of the Moldanubian Plutonic Complex. Both plutons have a peraluminous, high-K character formed by partial melting of a crustal metasedimentary (metapelite) source at relatively lower temperatures. The Mrákotín pluton (eastern part of the plutonic complex) was emplaced posttectonically at around 327 Ma and records a crucial role of magmatic stoping during magma ascent and emplacement. In contrast, the Klenov pluton (western part of the plutonic complex) was emplaced syntectonically with regional HT-LP tectonometamorphic event (formation of gently to moderately NNE dipping metamorphic schistosity).
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High-grade rocks of the Zábřeh Crystalline Complex
Jůzlová, Klára ; Lexa, Ondrej (advisor) ; Buriánek, David (referee)
This Bachelor thesis is focused on the Zábřeh Crystalline Unit and the belt of high-grade rocks in its southern part. The research is aimed to summarize existing knowledge about this unit, to correlate the Zábřeh Crystalline Unit with adjacent units and to confront various opinions on its position within the Bohemian Massif. The practical part of this thesis shows outputs of the initial phase of my ongoing research. Keywords: Zábřeh Crystalline Unit, Teplá-Barrandian Unit, Saxothuringicum, pre-Variscan tectonic evolution
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Fabrics and emplacement of Weinsberg - type granitoids (Moldanubian Batholith)
Pour, Ondřej ; Verner, Kryštof (advisor) ; Buriánek, David (referee)
English abstract This diploma 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 and Strážný 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 emplacement and crystallization of both studied magmatic bodies took place in cooperation with the final phases of S3-fabrics development. This "bavarian phase" has a character of heterogenous deformation with indications of the dextral subhorizontal shear (WNW-ESE strike). During this event, syntectonic emplacement and internal fabrics development of strážný pluton took place at ~322 Ma. The transpression was followed by the localized transtension tectonics in NE direction, probably in cooperation with exhumation of high-grade metamorphic rocks of Bavarian terrane. In this phase, at ~320 Ma, the granitoids of Prášily pluton were emplaced into the considerably exhumed crust of the Moldanubian region.
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Magnetic fabrics and emplacement of the Eisgarn granitoids (Moldanubian Plutonic Complex)
Paclíková, Jana ; Verner, Kryštof (advisor) ; Buriánek, David (referee)
English abstract We consider our preliminary results of structural and AMS analyses of granitoids of the Mrákotín and Klenov Plutons located in the northeastern part of the Moldanubian Plutonic Complex. Both plutons have a peraluminous, high-K character formed by partial melting of a crustal metasedimentary (metapelite) source at relatively lower temperatures. The Mrákotín pluton (eastern part of the plutonic complex) was emplaced posttectonically at around 327 Ma and records a crucial role of magmatic stoping during magma ascent and emplacement. In contrast, the Klenov pluton (western part of the plutonic complex) was emplaced syntectonically with regional HT-LP tectonometamorphic event (formation of gently to moderately NNE dipping metamorphic schistosity).
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