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Position of Saxonian granulite within the frame of European Variscides
Ramešová, Olga ; Jeřábek, Petr (advisor) ; Racek, Martin (referee)
The Saxonian Granulite Massif (the type granulite locality) is situated in the northwestern part of Bohemian Massif. It is an antiform with dome structure, which came to the surface from below SaxoThuringian Paleozoic units. It consits of high-pressure "Granulite core" with felsic and mafic granulites, which are surrounded by tectonic cover called "Schist mantle" of low-grade upper- crustal rocks. Massif is penetrated by several granite bodies. The Core and Mantle are separated by shear zone with a thickness of about 2 km. Geochronological dating of complex exhumation gives ages of about 340 Ma. The whole complex is affected by system of foliation and lineations. Massif was deeply buried, extremely heated and then exhumed with high exhumation rates during post collision extensional phase of the Variscan Orogeny.
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Conditions and mechanism of emplacement of the Saxon Granulite Massif in Saxothuringian
Ramešová, Olga ; Jeřábek, Petr (advisor) ; Štípská, Pavla (referee)
The Saxonian Granulite Massif in the Saxothuringian Domain of the Bohemian Massif, is represented by a single granulite body consisting of felsic and mafic granulites formed during Variscan tectono-metamorphic event. The granulites with peak metamorphic P-T conditions of ~2.3 GPa and 970-1060 řC (Fuhrman and Lindsley, 1988; Rötzler and Romer, 2001) were exhumed and emplaced into the palaeozic sedimentary cover sequence, which resulted into contact metamorphism affecting these metasedimentary rocks and development of a contact metamorphic aureole. In the map view, the granulite body has elongated shape with the long axis oriented in NE- SW direction and it is surrounded by the so called schist mantle reflecting the extent of the contact metamorphic aureole. Within two kilometers distance away from the contact with granulite body, the metamorphic grade in metasediments decreases from cordierite gneiss, andalusite bearing micaschist to phyllite. Detailed field structural analysis in the studied area revealed a deformation record associated with four main deformation phases. In granulites the oldest deformation fabric contains kyanite and sillimanite. This fabric is locally overprinted by the subhorizontal green schist facies fabric, mainly along the margins of the granulite body. In metasediments, the...
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Position of Saxonian granulite within the frame of European Variscides
Ramešová, Olga ; Jeřábek, Petr (advisor) ; Racek, Martin (referee)
The Saxonian Granulite Massif (the type granulite locality) is situated in the northwestern part of Bohemian Massif. It is an antiform with dome structure, which came to the surface from below SaxoThuringian Paleozoic units. It consits of high-pressure "Granulite core" with felsic and mafic granulites, which are surrounded by tectonic cover called "Schist mantle" of low-grade upper- crustal rocks. Massif is penetrated by several granite bodies. The Core and Mantle are separated by shear zone with a thickness of about 2 km. Geochronological dating of complex exhumation gives ages of about 340 Ma. The whole complex is affected by system of foliation and lineations. Massif was deeply buried, extremely heated and then exhumed with high exhumation rates during post collision extensional phase of the Variscan Orogeny.
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