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Association of Turonian echinoids at the Nebužely locality (Bohemian Cretaceous Basin)
Bartušková, Nikola ; Fatka, Oldřich (advisor) ; Ziegler, Václav (referee)
This diploma thesis is focused on morphological studies and taxonomic analyses of small regular and irregular echinoids found at the Nebužely locality; at this locality clastic sediments of Teplice Formation of Bohemian Cretaceous Basin are exposed. Presence of the belemnite Praeaxtinocamax bohemicus makes possible to assign the outcrop to late Turonian. Detailed morphological study of more than one hundred specimens enabled to distinguish four echinoids species (Echinogalerus, Glyphocyphus, Nucleolites, Phymosoma), less favourably preserved and/or very limited material is classified as belonging to two orders (Cidaroida, Holectypoida) and one family (Phymosomatidae), respectively. The next part of the thesis contains a possible palaeoecological reconstruction of the environment at the studied locality. Based on bathymetrically indicative molluscs, a shallow−water palaeoenvironment is suspected for this locality. Key words: echinoid, Bohemian Cretaceous Basin, Turonian
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Oyster bioherms in the Bohemian Cretaceous Basin
Rantuch, Jakub ; Košťák, Martin (advisor) ; Frank, Jiří (referee)
Frustration from shape and size variability of oyster's species Rhynchostreon suborbiculatum (Lamarck) is long known phenomenon. In current state of his systematic it is not possible to consider it fully satisfying. Is it is shown in study of genus Gryphaea by Jones and Gould (1999), that application of modern analytical methods, undoubtly lightens long-darkned places of evolution process. Idea of Videt and Neraudeau (2003), that shape variability of Rhynchostreon suborbiculatum (Lamarck) probably also mirrors heterochronic processes, introduces inspirative and good foundation for future research in this field. Occurence of this oyster is proved from huge range of sites in Bohemian Cretaceous Basin area. It is combination of rich occurance, unique preservation and variability of lithological settings, which gives us unique starting point for next step to solve significant problem. Based on population analyses consisting of biometrical studies supported by oxygen isotope analyses, in future, it will be possible to reach sufficient conclusions of this issue, and progress in our knowledge.
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Depositional architectures, stratigraphy, and depositional regime of Lower-Middle Turonian sandstone bodies, northwestern part of the Bohemian Cretaceous Basin
Skopcová, Monika ; Uličný, David (advisor) ; Čech, Stanislav (referee)
Sandstone bodies of the Lower and Middle Turonian well exposed in the northwestern part of the Bohemian Cretaceous Basin represent deposits of the coarse-grained deltas. Aim of this paper is to interpret the architectures, stratigraphy and depositional regime of these bodies. The main architectural elements are clinoforms which show intermediate dip 4ř to 5ř of the delta slope and the direction of the progradation of the delta to the west-southwest. Correlation of the lithological profiles with the well - log data provided the stratigraphic classification of the outcrops in the studied area mostly to the genetic sequence TUR2. Correlations in one of the two stratigraphic cross - sections revealed the existence of the second delta body prograding into the basin from Most - Teplice Palaeohigh during TUR1. Detailed study of the sedimentary structures in the outcrops show high degree of reworking of foresets by tidal generated current. Two main directions of the paleocurrents results from the analysis - dominant current to the NW and subordinate current to the SE - SSE.
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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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Foraminifera and Ostracoda as palaeoenvironmental and biostratigraphical indicators in Upper Cretaceous, Bohemian Cretaceous Basin
Chroustová, Markéta ; Holcová, Katarína (advisor) ; Skupien, Petr (referee) ; Soták, Ján (referee)
This PhD thesis is a commentary to the attached publications. The thesis deals with two microfossil groups Ostracoda and Foraminifera in the Upper Cretaceous of the Bohemian Cretaceous Basin. Contribution of these microfossils for biostratigraphy and application in palaeoenvironmental reconstruction with the modern approach is the main goal of this work. Basic ecology, biogeography and previous work in the Bohemian Cretaceous Basin is included. Studied fossil sites, methods, microfossil preservation and data evaluation are described below. Obtained palaeontological, geochemical and lithological data are interpreted in the context with available data from studied fossil sites. Ostracoda assemblage from Úpohlavy fossil site is correlated with the Ostracoda assemblage from Great Britain. The similarity of the Ostracoda taxa suggests a possible communication of compared areas. Thanks to this work, biostratigraphy occurrence of six Ostracoda species (Cythereloidea stricta, Nemoceratina (Pariceratina) montuosa, Cythereis ornatissima ornatissima, Phodeucythere cuneiformis, Pterygocythereis robusta a Bairdoppilata litorea) is extended to Upper Turonian. Taxonomical changes in studied ostracoda assemblage expressed by PSH hypothesis (Platycopid Signal Hypothesis) support previous palaeoenvironmental...
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Association of Turonian echinoids at the Nebužely locality (Bohemian Cretaceous Basin)
Bartušková, Nikola ; Fatka, Oldřich (advisor) ; Ziegler, Václav (referee)
This diploma thesis is focused on morphological studies and taxonomic analyses of small regular and irregular echinoids found at the Nebužely locality; at this locality clastic sediments of Teplice Formation of Bohemian Cretaceous Basin are exposed. Presence of the belemnite Praeaxtinocamax bohemicus makes possible to assign the outcrop to late Turonian. Detailed morphological study of more than one hundred specimens enabled to distinguish four echinoids species (Echinogalerus, Glyphocyphus, Nucleolites, Phymosoma), less favourably preserved and/or very limited material is classified as belonging to two orders (Cidaroida, Holectypoida) and one family (Phymosomatidae), respectively. The next part of the thesis contains a possible palaeoecological reconstruction of the environment at the studied locality. Based on bathymetrically indicative molluscs, a shallow−water palaeoenvironment is suspected for this locality. Key words: echinoid, Bohemian Cretaceous Basin, Turonian
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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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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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Oyster bioherms in the Bohemian Cretaceous Basin
Rantuch, Jakub ; Košťák, Martin (advisor) ; Frank, Jiří (referee)
Frustration from shape and size variability of oyster's species Rhynchostreon suborbiculatum (Lamarck) is long known phenomenon. In current state of his systematic it is not possible to consider it fully satisfying. Is it is shown in study of genus Gryphaea by Jones and Gould (1999), that application of modern analytical methods, undoubtly lightens long-darkned places of evolution process. Idea of Videt and Neraudeau (2003), that shape variability of Rhynchostreon suborbiculatum (Lamarck) probably also mirrors heterochronic processes, introduces inspirative and good foundation for future research in this field. Occurence of this oyster is proved from huge range of sites in Bohemian Cretaceous Basin area. It is combination of rich occurance, unique preservation and variability of lithological settings, which gives us unique starting point for next step to solve significant problem. Based on population analyses consisting of biometrical studies supported by oxygen isotope analyses, in future, it will be possible to reach sufficient conclusions of this issue, and progress in our knowledge.
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