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Tectonic evolution of the Mariánské Lázně Complex and of surrounding units
Hafoudh, Shumran ; Konopásek, Jiří (advisor) ; Franěk, Jan (referee)
Tectonic evolution of the western margin of the Bohemian Massif is the result of southeastward Devonian subduction of the Saxothuringian Ocean followed by collision of the Saxothuringian continental crust with the easterly lying Teplá-Barrandian Domain during early Carboniferous (e.g. Franke 2000). Northwestern flank of the Teplá Barrandian Domain is represented by mafic and ultramafic rocks of the Mariánské Lázně Complex usually considered as an ophiolite complex documenting the closure of the Saxothuringian Ocean (e.g. Kastl &Tonika, 1984, Beard et al., 1994). Mariánské Lázně Complex is in the NW thrust over medium-grade metabasites and metasediments of the Kladská Unit with suggested Saxothuringian affinity (Kachlík, 1993), and in the SE it is overthrust by medium- to highgrade metasediments of the Teplá Complex (Cháb & Žáček, 1994). Geochronological data show that the northwestern flank of the Teplá-Barrandian Domain was exhumed already during Upper Devonian (Dallmeyer & Urban, 1998) and suggest apparent lack of deformation and metamorphism associated with Carboniferous collision. Our study has concentrated on structural record along the profile from the Kladská Unit to the Teplá Complex in order to separate structures produced during Devonian subduction and exhumation from those developed during...
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The role of deformation partitioning on the tectonic evolution of the superstructure-infrastructure transition in the Teplá-Barrandian domain
Peřestý, Vít ; Lexa, Ondrej (advisor) ; Konopásek, Jiří (referee) ; Grasemann, Bernhard (referee)
Upper part of the orogenic crust (superstructure) significantly differs from the lower part of the crust (infrastructure) by structural and metamorphic record. This fundamental observation is explained by interruption of the mutual evolution due to mechanical decoupling of the hot and ductile infrastructure from the cold and brittle superstructure at certain stages of the orogenic evolution. The superstructure-infrastructure transition zone is a rheologically predisposed domain of sharp deformation and metamorphic gradients with polyphase structural record. Understanding of the deformation partitioning in such a rheologically complex setting is a key aspect in linking of the individual deformation stages between upper and lower crust. The transition zone between unmetamorphosed early-Variscan superstructure (Teplá-Barrandian Domain) and late Variscan high- grade infrastructure (Saxothuringian Domain) crops out at the western margin of the Teplá- Barrandian Domain in the Bohemian Massif. This area is a continuous mid- to lower-crustal section with early-Variscan structural and metamorphic record, which is superposed onto pre-Variscan episode. This thesis aims to decipher individual deformation events, to evaluate their manifes- tations at different crustal levels and to bring new and unifying...
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The role of deformation partitioning on the tectonic evolution of the superstructure-infrastructure transition in the Teplá-Barrandian domain
Peřestý, Vít ; Lexa, Ondrej (advisor) ; Konopásek, Jiří (referee) ; Grasemann, Bernhard (referee)
Upper part of the orogenic crust (superstructure) significantly differs from the lower part of the crust (infrastructure) by structural and metamorphic record. This fundamental observation is explained by interruption of the mutual evolution due to mechanical decoupling of the hot and ductile infrastructure from the cold and brittle superstructure at certain stages of the orogenic evolution. The superstructure-infrastructure transition zone is a rheologically predisposed domain of sharp deformation and metamorphic gradients with polyphase structural record. Understanding of the deformation partitioning in such a rheologically complex setting is a key aspect in linking of the individual deformation stages between upper and lower crust. The transition zone between unmetamorphosed early-Variscan superstructure (Teplá-Barrandian Domain) and late Variscan high- grade infrastructure (Saxothuringian Domain) crops out at the western margin of the Teplá- Barrandian Domain in the Bohemian Massif. This area is a continuous mid- to lower-crustal section with early-Variscan structural and metamorphic record, which is superposed onto pre-Variscan episode. This thesis aims to decipher individual deformation events, to evaluate their manifes- tations at different crustal levels and to bring new and unifying...
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Thermal and mechanical aspects of burial and exhumation mechanisms within the Moldanubian orogenic root in South Moravia and Lower Austria
Racek, Martin ; Štípská, Pavla (advisor) ; Konopásek, Jiří (referee) ; Janák, Marian (referee)
This thesis repÍesents results of petrological and stuctural investigations at the eastem margin of the Bohemian Massif. The main objective is the understanding of mechanical and thermal aspects of the formation and exhumation mechanisms of the Moldanubian orogenic root domain. The studies has been carried at the south-eastem margin of the Moldanubian zone in Lower Aushi4 at the contact with the Brunia basement and are presented in the frame of recently developed new concept of lower crust exhumation by vertical extrusion. The first part (Chapter 1-3) shows results of detailed structural mapping combined with petrological study and thermodynamical modeling of the metamorphic processes. Chapters I and 2 are concerned with the area around the Drosendorf window (Moldanubian domain, South Moravia and Lower Austria). The Chapter I deals with detailed petrological investigation of individual structwes in the E-W profile going from high-grade rocks of the Gftihl unit across the Drossendorf window to the Brunia basement. The petrological investigation shows existence of an internal domain (the Drosendorf window) composed of predominantly metasedimenatry rocks of mid-crustal origin that preserve a prograde metamorphism up to 8 kbar. This unit is surrounded by lower crustal rocks with peak metamorphic...
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