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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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Conodont platform elements from selected sections of Devonian and their application in biostratigraphic correlation
Formáčková, Aneta
The presented work consists of three separate papers that have been published in peer- reviewed journals. The published studies summarize and refine the existing knowledge about some conodont faunas of the Devonian with a primary focus on P1 elements and their potential in biostratigraphy. The dissertation thesis consists of three main parts. The first part is designed as an introduction, a summary of the objectives of the presented work, and methodologies used during the conodont sampling and sample processing and samples for thin sections. The second part of the work presents a general overview of the problems of conodont elements in biostratigraphy of the Devonian, characterizes the geological conditions and paleogeographic development of the areas from which the studied elements come from. The third part summarizes the results, brings a discussion on the herein presented data published in articles and contains the final word on the researched issues. The published studies on which this work is based are focused on platform elements of ozarkodinids and icriodontids, whose global distribution in time and space enables their study in different environments and stratigraphic levels. The microfacial characteristics of the studied sections and the issue of conodont biostratigraphy in the Devonian are...
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Conodont platform elements from selected sections of Devonian and their application in biostratigraphic correlation
Formáčková, Aneta ; Slavík, Ladislav (advisor) ; Kumpan, Tomáš (referee) ; Spalletta, Claudia (referee) ; Dojen, Claudia (referee)
The presented work consists of three separate papers that have been published in peer- reviewed journals. The published studies summarize and refine the existing knowledge about some conodont faunas of the Devonian with a primary focus on P1 elements and their potential in biostratigraphy. The dissertation thesis consists of three main parts. The first part is designed as an introduction, a summary of the objectives of the presented work, and methodologies used during the conodont sampling and sample processing and samples for thin sections. The second part of the work presents a general overview of the problems of conodont elements in biostratigraphy of the Devonian, characterizes the geological conditions and paleogeographic development of the areas from which the studied elements come from. The third part summarizes the results, brings a discussion on the herein presented data published in articles and contains the final word on the researched issues. The published studies on which this work is based are focused on platform elements of ozarkodinids and icriodontids, whose global distribution in time and space enables their study in different environments and stratigraphic levels. The microfacial characteristics of the studied sections and the issue of conodont biostratigraphy in the Devonian are...
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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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