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Study of bioapatite geochemistry using Laser Ablation ICP-MS
Kroupa, Vojtěch ; Doležalová Weissmannová, Helena (referee) ; Vašinová Galiová, Michaela (advisor)
This diploma thesis deals with topic of investigating bioapatite from conodont samples using laser ablation ICP-MS. The aim is to evaluate effect of diagenesis on the chemical composition and content of rare earth elements (REE) in the structure of conodonts. During diagenesis, bioapatite was transformed into mineral francolite and as part of this process, adsorbed REE into its crystalline structure. The degree of adsorption of REE was influenced by presence of seawater, presence of siliciclastics in surrounding REE-enriched rocks, redox conditions and also the effects of elements such as Mn and Fe present in the pore water. It was found that a group of conodont samples from the Col des Tribes (France) underwent a major diagenetic transformation, late recrystallization with REE desorption, and also due to the increased presence of Mn ions and influence of the original suboxic conditions contains rarer positive Ce anomalies. While groups of conodont samples from the Mramorový lom near Křtiny (Czech Republic) have undergone a minor diagenetic change, they contain a larger amount of REE elements.
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Study of bioapatite geochemistry using Laser Ablation ICP-MS
Kroupa, Vojtěch ; Doležalová Weissmannová, Helena (referee) ; Vašinová Galiová, Michaela (advisor)
This diploma thesis deals with topic of investigating bioapatite from conodont samples using laser ablation ICP-MS. The aim is to evaluate effect of diagenesis on the chemical composition and content of rare earth elements (REE) in the structure of conodonts. During diagenesis, bioapatite was transformed into mineral francolite and as part of this process, adsorbed REE into its crystalline structure. The degree of adsorption of REE was influenced by presence of seawater, presence of siliciclastics in surrounding REE-enriched rocks, redox conditions and also the effects of elements such as Mn and Fe present in the pore water. It was found that a group of conodont samples from the Col des Tribes (France) underwent a major diagenetic transformation, late recrystallization with REE desorption, and also due to the increased presence of Mn ions and influence of the original suboxic conditions contains rarer positive Ce anomalies. While groups of conodont samples from the Mramorový lom near Křtiny (Czech Republic) have undergone a minor diagenetic change, they contain a larger amount of REE elements.
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Rudist assemblages of the Upper Cretaceous "pocket" infills in the Teplice rhyolite - systeamtics, palaeoecology, stratigraphy
Křížová, Barbora ; Košťák, Martin (advisor) ; Čech, Stanislav (referee)
The study (MS, diploma thesis) is based on more than 1500 rudist samples from the Upper Cretaceous sediments of localities Písečný vrch and Na Stínadlech (near Teplice). Investigated samples come mainly from the collection of A. H. Fassel and were collected at the end of the 19th century, currently stored in the Regional museum in Teplice and National museum in Prague. The rudist shells were determined by generic and species levels, including five genera and eight species. The stratigraphic age of both localities has been a subject of discussion since the second half of the 19th century. In the recent decades, the opinion on the lower turonian age prevailed. However, five of the eight species present in the studied localities demonstrate the upper cenomanian age of the assemblages, making them probably the oldest known rudist-corals assemblages of its kind. The palaeoecological analysis and the ecological relationships proposal for the studied localities is based on the research in literature on palaeoecology and evolution of the rudists, also presented in the study. Key words: Bohemian Cretaceous Basin, Cenomanian - Turonian, rudists, corals, palaeoenvironment, Teplice rhyolite
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Rudist assemblages of the Upper Cretaceous "pocket" infills in the Teplice rhyolite - systeamtics, palaeoecology, stratigraphy
Křížová, Barbora ; Košťák, Martin (advisor) ; Čech, Stanislav (referee)
The study (MS, diploma thesis) is based on more than 1500 rudist samples from the Upper Cretaceous sediments of localities Písečný vrch and Na Stínadlech (near Teplice). Investigated samples come mainly from the collection of A. H. Fassel and were collected at the end of the 19th century, currently stored in the Regional museum in Teplice and National museum in Prague. The rudist shells were determined by generic and species levels, including five genera and eight species. The stratigraphic age of both localities has been a subject of discussion since the second half of the 19th century. In the recent decades, the opinion on the lower turonian age prevailed. However, five of the eight species present in the studied localities demonstrate the upper cenomanian age of the assemblages, making them probably the oldest known rudist-corals assemblages of its kind. The palaeoecological analysis and the ecological relationships proposal for the studied localities is based on the research in literature on palaeoecology and evolution of the rudists, also presented in the study. Key words: Bohemian Cretaceous Basin, Cenomanian - Turonian, rudists, corals, palaeoenvironment, Teplice rhyolite
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