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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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Miocene fish fauna from the Cheb and Sokolov Basins: taxonomic overview and palaeoecology
Hakalová, Pavla ; Přikryl, Tomáš (advisor) ; Mazuch, Martin (referee)
The aim of this thesis is to present an overview of Miocene fish fauna of the lacustrine sediments in the Cheb and Sokolov Basins, geological settings of this area, and fish associations in individual biozones. Sediments of Cheb and Sokolov Basins were deposited during time interval from Eocene until Miocene in the subtropical zone of the North hemisphere. Volcanic and post-volcanic activities of the Ohárecký rift influenced development of these basins. It's possible define two time sections within development of these basins: early and later; both of them provide rich record of fossil fishes. For the early period of the development is typical smaller range of the lake and its shallow depth. The relicts of this stage are limited to Cheb Basin mainly. Fish fossil record is limited, with three species only: Esox sp., Palaeotinca egeriana and Leuciscus (Palaeoleuciscus) socoloviensis. Low fish diversity could have been affected by poor living conditions or lower taxonomic diversity in general during this time. The later developmental period was much longer. The lake was much bigger - it spread to Sokolov Basin also. The fish fauna diversity is much higher, including taxons Paleotinca egariana, Leuciscus (Palaeoleuciscus) socoloviensis, Aphanius chebianus, Paralebias egeranus and Gobius sp. It is...
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Charcoal layers in the Main Coal of central part of the Most Basin - a potential indicator of climate changes in early Miocene?
Šulc, Jan ; Opluštil, Stanislav (advisor) ; Pešek, Jiří (referee)
This thesis is summing up the exploration of fusite layers in the middle coal bench of the main coal seam in the Most Basin, studied with support Severočeské doly a. s. in the Bílina opencast mine. These layers are interpreted as a result of wild fires of wetland vegetation and represent charcoal horizons. Several methods have been used for research of these layers. These include four lithological profiles throughout the middle coal bench in different places of Bílina opencast mine, usage of non-core drilling data (speed and force of auger) and comparation of these data with the profiles, and finally, the maceral analysis of the part of the middle bench between two flooding horizons marked by carbonaceous clay partings. Observations indicate that the charcoal layers are hardly recognisable because of their small thickness (few centimetres maximum) and lenticular nature (their lateral continuity usually does not exceed several tens of meters). The coreless drilling according to its sensitivity shows the potential of its usage for identification of fusite layers, although comparison with nearby field section is recommended. Maceral analysis shows that huminite is in favour against liptinite and inertinite. It is clear from the data, that the fusite layers were created as a result of burning...
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Neovolcanic Rocks of the SW part of the Most Basin in the area of Tušimice power plant open pit
Sobotka, Martin ; Kachlík, Václav (advisor) ; Novotný, Tomáš (referee)
Diploma thesis deals with geological, petrological and geochemical studies of neovolcanic rocks of the SW part of the Most Basin in the area of Tušimice power plant open pit. There are two lava flows affected by coal mining in northern part of the mine. Petrological and geochemical studies with K-Ar dating relatively recent rocks in mostly weatherworn volcanic rocks showed, that they can be classified as Ti-rich basaltic rocks without olivine (tephrites), which belong to the main volcanic phase in the evolution of the Eger graben. It was evidenced geologicaly and with K-Ar dating, that studied rocks were seperated from underlying beda by hiatus which caused erosion of volcanic rocks as well as crystalline bedrock. Mmajor and trace elements composition of co-magmactic volcanics showed that rock were derived from two slightly different sources of upper mantle. Composition of two samples indicates the formation from low degree of partial melting strongly metasomatic asthenospheric mantle. Chemical features of volcanic rocks show that mantle source was comparamble to recent OIB basalts. Last sample arose from less metasomatized and depth distincted mantle which was affected by higher level of partial melting. Melts from which crystallized both rocks were minimaly affected by asimilation or...
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Geochemical markers from foraminiferal tests as a tool for reconstruction of paleoceanological environments: a case study from the Miocene of the Central Paratethys
Scheiner, Filip
This thesis deals with the use of geochemical proxies on foraminifera for paleoceanographical, paleoecological and paleoenvironmental interpretations in the fossil epicontinental sea - the Central Paratethys during the Langhian. It discusses the used methodologies and approaches that were specially chosen to fit the problematic of the studied area such as the single test analysis of carbon and oxygen stable isotopes on foraminifera. Other geochemical methods were represented by Mg/Ca based paleothermomethry and by several organic geochemistry proxies on whole rock samples (n-alkane indices, δ13 Corg, and carbon ratios - TOC/TIC/TC). These were further combined with foraminiferal paleoecological data, which allowed identification of particular water masses in the studied region as well as the prevailing circulation patterns/regimes during the studied interval in the Paratethyan marine realm. Additionally, there were interpreted various regional paleoenvironmental and paleoecological consequences. The Paratethys had similar hydrography of surficial waters with the Mediterranean, conversely to the bottom waters that were different, probably of a regional origin with their own evolution during the studied time interval. The anti-estuarine circulation regime, which was probably linked with the closure...
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Geochemical markers from foraminiferal tests as a tool for reconstruction of paleoceanological environments: a case study from the Miocene of the Central Paratethys
Scheiner, Filip
This thesis deals with the use of geochemical proxies on foraminifera for paleoceanographical, paleoecological and paleoenvironmental interpretations in the fossil epicontinental sea - the Central Paratethys during the Langhian. It discusses the used methodologies and approaches that were specially chosen to fit the problematic of the studied area such as the single test analysis of carbon and oxygen stable isotopes on foraminifera. Other geochemical methods were represented by Mg/Ca based paleothermomethry and by several organic geochemistry proxies on whole rock samples (n-alkane indices, δ13 Corg, and carbon ratios - TOC/TIC/TC). These were further combined with foraminiferal paleoecological data, which allowed identification of particular water masses in the studied region as well as the prevailing circulation patterns/regimes during the studied interval in the Paratethyan marine realm. Additionally, there were interpreted various regional paleoenvironmental and paleoecological consequences. The Paratethys had similar hydrography of surficial waters with the Mediterranean, conversely to the bottom waters that were different, probably of a regional origin with their own evolution during the studied time interval. The anti-estuarine circulation regime, which was probably linked with the closure...
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Geochemical markers from foraminiferal tests as a tool for reconstruction of paleoceanological environments: a case study from the Miocene of the Central Paratethys
Scheiner, Filip ; Holcová, Katarína (advisor) ; Grunert, Patrick (referee) ; Demeny, Attila (referee)
This thesis deals with the use of geochemical proxies on foraminifera for paleoceanographical, paleoecological and paleoenvironmental interpretations in the fossil epicontinental sea - the Central Paratethys during the Langhian. It discusses the used methodologies and approaches that were specially chosen to fit the problematic of the studied area such as the single test analysis of carbon and oxygen stable isotopes on foraminifera. Other geochemical methods were represented by Mg/Ca based paleothermomethry and by several organic geochemistry proxies on whole rock samples (n-alkane indices, δ13 Corg, and carbon ratios - TOC/TIC/TC). These were further combined with foraminiferal paleoecological data, which allowed identification of particular water masses in the studied region as well as the prevailing circulation patterns/regimes during the studied interval in the Paratethyan marine realm. Additionally, there were interpreted various regional paleoenvironmental and paleoecological consequences. The Paratethys had similar hydrography of surficial waters with the Mediterranean, conversely to the bottom waters that were different, probably of a regional origin with their own evolution during the studied time interval. The anti-estuarine circulation regime, which was probably linked with the closure...
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Fossil marlins (family Istiophoridae) from the Piña locality (Panama; Chagres Formation; Miocene) - morphology and comparison with related forms
De Gracia Castro, Carlos Fernando ; Přikryl, Tomáš (advisor) ; Carnevale, Giorgio (referee)
The study of fossil istiophorids is limited by its fragmentary fossil record; the absence of osteological specimens for comparisons; the cryptic bibliography of several early works and the absence of more accurate comparative methods. Appling a data imputation model we took advantages of extant data for rostral and articular variables for istiophorid billfishes. We used this result to apply PCA analysis and we compared fossil and modern istiophorids together. With this analysis we present here two new istiophorid species: Makaira? sp. nov. 1 and Makaira sp. nov. 2. Makaira? sp. nov. 1 is the most complete fossil istiophorid ever discovered and represent that share characters in various genera. We hypothesize that characters in bones involved in alimentation process have phylogenetic importance as: rostrum shape, denticles, lower jaw, vomer, basioccipital and skull shape as well as orbital size. Our taxonomic reviews of fossil istiophorid reorganize its taxonomy and solve many conflicts about the classification of fossil species. The istiophorids are abundant macrovertebrate in the Chagres sediments and its presence suggests a water column with a minimum of 200m depths in an environment of short platform with oceanic influence. Given the high productivity inferred in this environment we suggest that...
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Chemostratigraphy of the Holešice Member in the Most basin (Miocene)
Müllerová, Eliška ; Opluštil, Stanislav (advisor) ; Martínek, Karel (referee)
The newest geochemical and sedimentological studies of the Libkovice Member in the Most Basin revealed existence of a sedimentary cyclicity that is controlled by the change of Earth's orbital parameters and the shape of its orbit. The main objective of this study is to verify the hypothesis whether there is also a similar cyclical record in strata underlying the Libkovice Member. This interval located in top of the Holešice Member consists of lacustrine sediments of a smaller extent represented by the so-called Břešťany Clays. The aim of the diploma thesis was a geochemical analysis of the concentration of selected elements measured by a mobile XRF device from the drilling cores in the stratigraphic interval between the roof of the Main Coal and the base of the Libkovice Member. Also made was a litological description of boreholes and sedimentary texture of selected clay samples. A mineralogical analysis was performed using the X-ray diffraction method. Usefulness of the XRF mobile device was proven especially for the heavier elements (e.g., Fe and Sr) and less for the lighter elements K and Ti. Nevertheless, it was possible to assign the analysed sediments to the already published chemostratigraphic subdivision of the Most Basin and to confirm its validity. The Břešťany Clays horizon was identified...
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Neovolcanic Rocks of the SW part of the Most Basin in the area of Tušimice power plant open pit
Sobotka, Martin ; Kachlík, Václav (advisor) ; Novotný, Tomáš (referee)
Diploma thesis deals with geological, petrological and geochemical studies of neovolcanic rocks of the SW part of the Most Basin in the area of Tušimice power plant open pit. There are two lava flows affected by coal mining in northern part of the mine. Petrological and geochemical studies with K-Ar dating relatively recent rocks in mostly weatherworn volcanic rocks showed, that they can be classified as Ti-rich basaltic rocks without olivine (tephrites), which belong to the main volcanic phase in the evolution of the Eger graben. It was evidenced geologicaly and with K-Ar dating, that studied rocks were seperated from underlying beda by hiatus which caused erosion of volcanic rocks as well as crystalline bedrock. Mmajor and trace elements composition of co-magmactic volcanics showed that rock were derived from two slightly different sources of upper mantle. Composition of two samples indicates the formation from low degree of partial melting strongly metasomatic asthenospheric mantle. Chemical features of volcanic rocks show that mantle source was comparamble to recent OIB basalts. Last sample arose from less metasomatized and depth distincted mantle which was affected by higher level of partial melting. Melts from which crystallized both rocks were minimaly affected by asimilation or...
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