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Mechanical interactions of subducting oceanic plates with the overriding accretionary wedges
Tkáčiková, Tatiana ; Žák, Jiří (advisor) ; Kusbach, Vladimír (referee)
Analog models have been widely used as a tool to reconstruct and understand the geological process, too great to observe in real-time. Subduction of solid mass seamounts, the significant topographic elevations, was focus of several studies by analogue "sandbox" and numerical modeling of recent years. However, the natural seamounts are commonly surrounded by loose blocks as a part of the Ocean Plate Stratigraphy. This thesis focuses on the topography of the ocean basin, analog modeling of seamount subduction and the effect of the topographic elevations on the deformation of the accretionary prism, during subduction of the various shapes of seamounts. A series of experiments were performed to study these processes and specially, the effect of the loose blocks on the structure of the wedge stratigraphy, particularly, on formation of mélanges.
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Record of Cambro-Ordovician Extension in the Teplá Crystalline Unit
Jašarová, Petra ; Racek, Martin (advisor) ; Kusbach, Vladimír (referee)
In my thesis I would like to summarize informations about SW part of the Teplá- Barrandian Unit. Particularly interesting situation is in the Teplá Crystalline Complex and Mariánské-Lázně Complex during Cambro-Ordovician rifting. At the beginning I will remind some basic information about Bohemian Massif (evolution and distribution). The next part of the thesis is dedicated to the west part of the Teplá-Barrandian Unit in the context of sedimentary record in the eastern part of the Unit. In two other captures is described Teplá Crystalline and Domažlice Crystalline Complex with emphasis on the plutons, which help us to reveal evolution of this area. In the third part of the thesis I will characterize Mariánské- Lázně Complex (lithology, dating and evolution). This complex was interpreted as a dismembered Cambro-Ordovician metaophiolite complex affected by Variscan subduction. But the latest studies show that the HP rocks protoliths are late Cadomian age, thus the eclogites probably originated during exhumation of this area. According to new results the Mariánské-Lázně Complex represent a metamorfic core complex and the Teplá Crystalline Complex is the detached roof of it. The corronitic metagabbros on the border between Mariánské-Lázně and Teplá Crystaline complex are generally interpreted to be...
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Thermobarometry of ultramafic rocks in ophiolites of the Vardar Zone in FYR Macedonia
Fikar, Lukáš ; Skála, Roman (advisor) ; Kallistová, Anna (referee)
This thesis is divided into review section followed by an experimental part. The first part focuses on geothermobarometry, illustrates its history and provides its detailed principles. Furthermore, it discusses various possibilities of the use of different mineral assemblages for purposes of thermometry and barometry. This part puts an emphasis on exchange reactions, the role of solvus in themometry, reactions based on weight transfers, and reactions involving gas phases. A chapter on Macedonian geography and regional geology provides a detailed description of the Vardar ophiolite belt, which was the source of the samples used in experimental part of the thesis, and its relationship toand other geological units in Macedonia, namely the Eastern Vardar Ophiolite zones, the Kopaonik unit, and the western part of the Vardar Ophiolite zone. Finally, a process of exsolution in subsolidus, which is impostant for the group of pyroxenes, is discussed. The area of interest is the use of the process of exsolution in thermometry. The thermodynamic conditions for exsolution are important features of the exsolution. The experimental part of the thesis includes a description of the samples and results of chemical analyses carried out with an electron probe microanalyzer. Chemical data were processed with two...
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Record of Cambro-Ordovician Extension in the Teplá Crystalline Unit
Jašarová, Petra ; Racek, Martin (advisor) ; Kusbach, Vladimír (referee)
In my thesis I would like to summarize informations about SW part of the Teplá- Barrandian Unit. Particularly interesting situation is in the Teplá Crystalline Complex and Mariánské-Lázně Complex during Cambro-Ordovician rifting. At the beginning I will remind some basic information about Bohemian Massif (evolution and distribution). The next part of the thesis is dedicated to the west part of the Teplá-Barrandian Unit in the context of sedimentary record in the eastern part of the Unit. In two other captures is described Teplá Crystalline and Domažlice Crystalline Complex with emphasis on the plutons, which help us to reveal evolution of this area. In the third part of the thesis I will characterize Mariánské- Lázně Complex (lithology, dating and evolution). This complex was interpreted as a dismembered Cambro-Ordovician metaophiolite complex affected by Variscan subduction. But the latest studies show that the HP rocks protoliths are late Cadomian age, thus the eclogites probably originated during exhumation of this area. According to new results the Mariánské-Lázně Complex represent a metamorfic core complex and the Teplá Crystalline Complex is the detached roof of it. The corronitic metagabbros on the border between Mariánské-Lázně and Teplá Crystaline complex are generally interpreted to be...
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