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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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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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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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Aspects of the high latitude environments in Cretaceous and Paleogene with special respect to land plants
Chernomorets, Oleksandra ; Sakala, Jakub (advisor) ; Dašková, Jiřina (referee)
This work is focused on the problematics of high latitudes in Cretaceous and Paleogene. The introduction describes and defines high latitude regions as well as their main characteristics nowadays. This allows one to achieve a better understanding of the substantial differences of these regions nowadays and in the geological past. The work itself then provides a brief description of the palaeographic position of the Arctic and Antarctic regions, their palaeoclimatic situations, organisms inhabiting their terrestrial and marine environments and their adaptation mechanisms. Further, a more detailed review of the land plants is presented. The last part is dedicated to the specific survival strategies of the land plants in the polar regions during the warm geological periods. On the basis of the studied literature, this work attempts to answer the questions: which strategy for adaptation to the high latitudes was used by the plants and whether being evergreen or deciduous was more effective on survival during the long and relatively warm polar nights. In conclusion, the relevance of the research of high latitude regions during the Cretaceous and Paleogene greenhouse type of climate is introduced in relation to the possible future consequences of the global warming. Key words: Cretaceous, Paleogene, land...
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Lower Turonian ammonites of the Bohemian Cretaceous Basin: taxonomic synopsis, stratigraphy and palaeoecology
Kohout, Ondřej ; Košťák, Martin (advisor) ; Ziegler, Václav (referee)
This thesis summarizes the findings of lower Turonian ammonites of the Bohemian Cretaceous Basin (BCB). It presents an overview of the most important taxonomic species and their brief morphology and paleoecology. Marginally, it describes sedimentary facies of the BCB which belongs to the lower Turonian ("Bílá Hora" Formation). Part is devoted to determining the stratotype between Cenomanian and Turonian, to the events that occurred during this period (CTBE, OAE II) and their impact on biocoenosis of early Turonian ammonites. This thesis tries to comprehend the importance of ammonites biostratigraphy to define the Lower Turonian and basic ammonites zones, which belongs to this period. Defining stratotype Cenomanian / Turonian has not yet been satisfactorily resolved and this work is the basis for further research and study. Key words: ammonite, Bohemian Cretaceous Basin, biostratigraphy, Turonian, paleoecology
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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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