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Petrogenesis and evolution of the Davle Volcanic Complex
Santolík, Václav ; Ackerman, Lukáš (advisor) ; Krmíček, Lukáš (referee)
The Davle Volcanic Complex (DVC) situated in the Teplá-Barrandian unit (TBU) of the Bohemian Massif, is considered as a Neoproterozoic-Cambrian magmatic arc that developed on the northern active margin of Gondwana supercontinent during Cadomian accretionary orogeny. This study combines data obtained from fieldwork, petrography, rock-forming mineral microanalysis, major and trace element analysis, Sr-Nd-Pb isotopic systematics and U-Pb zircon geochronology in order to reveal the petrogenesis and evolution of the DVC. At least three-stage metamorphism including Cadomian seafloor alteration, Variscan regional metamorphism as well as contact metamorphism related to the emplacement of the Central Bohemian Plutonic Complex affected the DVC. The studied rocks follow calc-alkaline trend whereas tholeiitic trend previously reported is rather related to younger magmatic events. The northern part of the DVC is dominated by felsic subvolcanic (plagiogranite), volcanic (dacite- rhyolite) and pyroclastic (dacitic-rhyolitic tuffs and breccias) rocks with a few outcrops of basaltic andesite-andesite pillow lavas documenting the subaqueous activity of the DVC. These rocks are Na-rich, but K-poor, the plagiogranite contains albite most likely primary in origin, and exhibit highly radiogenic εNd values (~ +6 to +11),...
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Comprehensive methodology for non-destructive microanalysis of colour layers and micro-traces
Hradil, David ; Grygar, Tomáš ; Bezdička, Petr ; Kotrlý, M. ; Hradilová, J. ; Kolář, P. ; Turková, I. ; Svoboda, M. ; Kurková, H. ; Grünwaldová, Veronika ; Bláhová, Anna
Comprehensive methodology for non-destructive forensic expert examinations of microscopic samples of colour layers (i.e. fragments of lacquer systems in a broad sense, and similar materials) has been created. This comprehensive methodology encompasses sample preparation as polished sections and microtome slices, and subsequent set of non-destructive analytical methods (based on SEM, EDS, XRD, FTIR, optical microscopy and pattern analysis), which lead to identification and comparison of materials in one sample (without its exhausting or irreversible modifications). Implementation of this system into forensic-technical expert casework allows realisation of some types of expert examinations and, first and foremost, maintaining probative value of the evidence (with respect to non-destructive microanalytical procedures), primarily in terms of explaining crimes of extreme gravity in the field of violent and organized crime.
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