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Tracing Microendolithic Ichnocenoses: A paleoecological and taphonomic approach over the Phanerozoic
Herenio Kerkhoff, Marta Leticia ; Holcová, Katarína (advisor) ; Skupien, Petr (referee) ; Soták, Ján (referee)
The microbial endoliths study from the Western Carpathians region was a semi-quantitative survey that included six sampling localities. Samples, ranging from Upper Oligocene to Miocene (Serravalian), came from three localities in Czechia (Mikulov, LOM-1 and Hevlín), two in Slovakia (DNV and LKŠ) and one place in Hungary (Tard Clays, Rozalia Quarry). The main goal of this project was to verify how different levels of hypoxia, established for studied intervals, would affect the microendolilthic assemblages present in tests of benthic foraminifera. Additionally, microbial activity and byproducts, and the overall interplay between bioerosion and bioprecipitation are also analysed. The degree of hypoxy was established using ratio of oxic/dysoxic and hypoxic foraminifera, defined as Benthic Foraminifera Oxygen Index (BFOi) Sampled index shows a predominance of dysoxic indicators, with rare oxic elements. Secondary electron elemental analysis (EDX) reveals a significant enrichment of sulphur, phosphorus and iron in biofilm samples from DNV and Hevlín, when compared to the rock matrix surrounding it. Resin casts reveal a predominance of Dysphotic to Deep Euphotic zones ichnocenosis, with a predominance of Chlorophyte, Rodophyte and heterotroph burrows. Few representatives of Cyanobacteria traces, such as...
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Fossil clown beetles (Coleoptera: Histeridae): early evolution of "beetle tanks"
Simon Pražák, Jan ; Prokop, Jakub (advisor) ; Růžička, Jan (referee)
Clown beetles (Histeridae) represent a diverse (>4500 described species) group of beetles with worldwide distribution (except Antarctica) and with exceptional diversity of occupied habitats. Specialisation on environments such as subcortical space, dung and carrion, tunnels of wood- boring insects, caves, sand deserts, beaches, rodent burrows or ant colonies, has led to remarkable adaptations of morphology and even radical changes of entire body shape. To understand evolutionary paths of this extraordinary group of beetles, fossils are of vital importance. In this study, I examined eight undescribed species of fossil Histeridae from mid-Cretaceous Burmese and Hkamti ambers. I provide morphological descriptions and discuss possible taxonomical position of these species based on morphological characters. I further tested the phylogenetic position of all Cretaceous Histeridae genera via a topology-constrained maximum parsimony analysis based on a set of 69 characters. Among the studied species, representatives of Abraeini and Paromalini are reported for the first time from the Cretaceous. I discuss evolutionary implications based on the new as well as other Histeridae fossils. Subcortical strategy was likely common in the Cretaceous histerids, now reported in three separate lineages. It is also...
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Klikov Formation in a newly localized landslide area near České Budějovice
Pilařová, Eliška ; Jerman, Jan (advisor) ; Mužík, Vlastimil (referee)
Diploma thesis is focused on obtaining new knowledge about the Klikov Formation of the České Budějovice Tertiary Basin during the extraordinary opportunity of construction a section of the D3 highway at the southern edge of České Budějovice near the villages of Roudné and Včelná. The location is also interesting because of newly detected landslide. The route of the highway is designed in large side-hill cut. The cut reached a total height of up to 20 m and was mainly carried out in the soft rock of the Klikov Formation, while vertical rock slopes up to several meters high remained without any stabilization during excavation. This made it possible to examine the soft rock of Klikov Formation in various aspects, e.g. stability, structural properties, properties of the rock material itself, etc. The text is divided into two parts. The first part describes construction works during the excavation of side cut, and the second to laboratory tests. The diploma thesis presents the connection between field observation and laboratory results.
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Calcareous nannofossils assemblages for provenance analysis of European paintings: From the sample preparation to the assemblage comparison
Jaques, Victory Armida Janine ; Holcová, Katarína (advisor) ; Caruso, Francesco (referee) ; Oszczypko-Ciowes, Marta (referee)
This PhD thesis is a commentary of four studies published and a fifth study submitted in peer reviewed and impacted scientific journals. Three studies are methodological work for the preparation of painted micro-samples to improve the measurements accuracy, the samples visualisation, and the combination of measurements methods. The two other papers focus on the fossil assemblages determination and comparison between reference historical areas and original paintings. This work is divided into three main parts, namely the introduction, the methods, and the calcareous nannofossils assemblages. In the introduction, detailed explanations are given about the paintings, historical materials, trade roads, what are nannofossils, how and why to use them. In the methods section, developed preparatory methodologies are summarised, and the most important results are explained. In the third part, the nannofossils assemblages, the differences between the assemblages from different areas in Europe compared to original paintings are explained and correlated to the literature. The impact of the preparatory methods on the results is discussed, and a conclusion is drawn from it in the context of painted artefacts in the Cultural Heritage field are unique, and so are the micro-samples from them. To extract most...
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Radiolaria of the Bohemian Cretaceous Basin
Müllerová, Petra ; Holcová, Katarína (advisor) ; Vajskebrová, Markéta (referee)
The first part of work deals with cell structure, shell morphology, reproduction and nutrition. Also the ecology and systematical subdivision of radiolarians are described here. The systematical subdivision depends on differences in shell morphology of individual forms. The next part is devoted to Cretaceous radiolarians with focus on Cenomanian and Turonian ones, also some examples from several locations around the world is located here. The last part of this work deals with geology of Bohemian Cretaceous Basin, where the study of radiolarians from certain site will continue in master thesis.
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Trace elements in carbonates of the Czech Creataceous Basin
Štěpánková, Anna ; Procházka, Václav (advisor) ; Štaffen, Zdeněk (referee)
The presented work is focused on research of distribution of trace elements in carbonate sediments and fossils in the Bohemian Cretaceous Basin. To obtain maximum information about the composition of the primary carbonate and its crystallization environment, the trace elements were analyzed mainly in fractions soluble in diluted acid. Another objective is the comparison of trace-element abundance in the soluble fraction and in the residue (or in the total mass of the samples). The results show that there are no systematic differences in the chemical composition of the original carbonate between various regions and stratigraphic positions (Cenomanian - upper Turonian). Elements like Sr, Mg and Mn in carbonate were affected by diagenesis, but contents and mutual ratios of the rare earth elements in all carbonates are similar and are characterized by negative cerium anomaly. The Ce-anomaly could be attenuated by elevated content of clastic matter, and in the soluble portions ocassionally via contamination by secondary phosphate. On the other hand, soluble fractions of limonite-rich and calcite-poor sandstones have positive cerium anomaly, which is the effect of Ce-sorbtion on limonite.
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Paleoecology of the Turonian Ostracoda from the Úpohlavy section
Houdková, Markéta ; Kyška Pipík, Radovan (advisor) ; Seko, Michal (referee)
This thesis deals with the class Ostracoda from the Úpohlavy quarry, which is an important paleontological site of the Turonian in the Czech Cretaceous Basin with abundant and well- preserved fauna. Twenty samples from marls and limestones of Jizera and Teplice formation were colected in which 36 marine middle and upper Turonian ostracods species were identified. Ostracods of the studied profile are characterized by gradual increase of species richness and decline of dominance of Cytherella cf. ovata (Roemer, 1840). The lowest diversity is in the Jizera formation and the highest diversity in the Teplice formation. The order Platycopida prevails on the order Podocopida in the Jizera formation, in which percentages of Platycopida is in the range 67-89%, while its percentage in the Teplice formatiion is lower in the range 25-59 %. Using the Platycopida Signal Hypothesis in a sense of Whatley et al. (2003), which compares percentages of Platycopida and Podocopida, a low O2 content in Jizera formation and in the Coprolite bed (monotonous dark marls) of Teplice formation is supposed. This is in accordance with low number of species (5-11 per sample) and with higher TOC content (0.34-0.74 %). With the beginning of limestone and marl sedimentation of the Teplice formation a number of species increases...
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Autecological study of selected Cretaceous plants using stable Carbon isotopes
Zahajská, Petra ; Kvaček, Jiří (advisor) ; Diefendorf, Aaron (referee)
1 Abstract This thesis presents an analysis of fossil plants from the Cenomanian Peruc-Korycany Formation of the Bohemian Cretaceous Basin and from the Bückeberg Formation of the Lower Saxony Basin in Germany. Based on earlier studies, both areas provide sediments that are considered to have developed in tidally influenced fluvial systems. Studied fossil plants are represented by ginkgoalean plant leaves (Ertemophyllum, Tritaenia), branches of conifers (Frenelopsis) and lauroid angiosperms (Eucalyptolaurus). Frenelopsis, Eretmophyllum and Tritaenia are considered to be halophytic plants, while Lauroid angiosperms were considered to grow in fresh water conditions. The fossil plants were studied using cuticle analysis and two methods of stable carbon isotope analysis: Bulk carbon isotope analysis and Compound Specific Isotope analysis. For cuticle analysis samples were observed and documented macroscopically and microscopically. To specify the environmental conditions, recent samples from three salt marshes in Great Britain were studied and analysed using the same methods as the fossil samples. The data from all observations and measurements were processed and their interpretation supported the modelled environment based on the sedimentological data. Frenelopsis were growing in a haline environment with low...
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Impact of being evergreen or deciduous on the wood anatomy of the trees in polar regions during the warm geological period : case study from Upper Cretaceous of the James Ross Island (Antarctic Peninsula)
Chernomorets, Oleksandra ; Sakala, Jakub (advisor) ; Gryc, Vladimír (referee)
Global warming and its influence on the environment has become a popular and widespread issue. Nowadays, an analogy of a high latitude ecosystem during the greenhouse type of climate does not exist. The Cretaceous polar ecosystem gave us a unique possibility of understanding these extreme ecosystems and the specific adaptations of organisms to these conditions. Such types of ecosystem are crucial for a better understanding of possible future climate changes. This thesis focusses on the adaptation strategies of land plants during the Late Cretaceous in the Arctic peninsula. The land plants responded to these specific solar conditionals in two different ways: evergreen or deciduous. The fossil material for this study comes from Brandy Bay and Crame Col, James Ross Island, Antarctic. The material was collected in a continuous sequence from Kotic point to Santa Marta Formation (Cenomanian - Companian). A detailed and systematic analysis was performed on five out of fifty-five samples that well represented the studied region and age: Agathoxylon kellerense, Agathoxylon antarcticus, Araucarioxylon chapmanae, Podocarpoxylon multiparenchymatosum and Phoroxylon sp. Based on the detailed study of Agathoxylon kellerense (sample number AN34) wood anatomy and growth rings structure, adaptation strategies were...
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