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Petrology and genetic relationships of alkaline intrusive rocks of the Roztoky Intrusive Complex
Mysliveček, Jakub ; Verner, Kryštof (advisor) ; Mlčoch, Bedřich (referee)
Roztoky Intrusive Center (33-28 Ma) is connected with tertiary volcanic activity in the territory of the Bohemian Massif (Czech Republic). It is located in the České středohoří volcanic complex on the tectonic line of the Ohře rift. The aim of this work was to petrologically describe local rocks and to verify the possible connection of the Roztoky Intrusive Center (RIC) with carbonatite magmatism, as could be suggested by the presence of alkaline rocks including their exotic types (essexites, monzodiorites, sodalitic syenites,…). It is assumed that there is a hidden carbonatite intrusion under the RIC caldera structure, which may also indicate geophysical manifestations of two hidden gravimetric minimas. In a detailed exploration of a drill core from the R-2 borehole from the 1960s, a petrographic rocks composition of a part of the caldera filling was described, including new find of xenolite of carbonatite in 286,5 m of R-2 borehole. By means of geochemical and micro-probe analyzes the well material including carbonatite was examined in detail. Carbonate mineralization with high REE contents was found in carbonatite, but also in the exocontact of the previously described silicocarbonatite (Rapprich et al. 2017). The discovery of carbonatite xenolite and the presence of minerals with high concentrations of...
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Petrology of differentiated alkaline, high-level intrusive bodies in the Zahořany - Chotiněves belt
Mysliveček, Jakub ; Verner, Kryštof (advisor) ; Erban, Vojtěch (referee)
The aim of the work was petrological research focused on alkaline volcanic bodies in line between villages Zahořany - Chotiněves near Litoměřice. Part of the area is covered by Tertiary volcanism products, which affected large parts of Europe and in our territory extends in the form of extensional structure of Ohře rift. The Field of studied objects is located nearby the southern edge of České středohoří vulcanic complex and the northern edge of the Central Volcanic Field. The question was whether studied area belongs, if it's still České středohoří volcanic complex or it belongs to Central Bohemian volcanic field. The area was visited several times for determinate the volcanic bodies and have been identified six localities which were collected rock samples for geochemical analysis and Probe Micro Analysis. Also, the detailed mapping of the bodies and their spatial extensions was performed because currently available geological map of 1: 50 000 do not correspond to reality. The area is situated close to Litoměřice break, which probably caused the linear distribution of magma in the direction of fracture, approximately NE - SW. Studied rocks by the classification TAS are classified as basaltic trachyandesites and are mainly composed by plagioclase, clinopyroxene, magnetite and to a small extent from biotite...
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