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Depositional architectures, stratigraphy, and depositional regime of Upper Turonian sandstone bodies, northwestern part of the Bohemian Cretaceous Basin
Vacková, Lenka ; Uličný, David (advisor) ; Bábek, Ondřej (referee)
This diploma thesis presents a synthesis of fieldwork and well-log data of the Upper- Turonian sandstone bodies in the northwestern part of the Bohemian Cretaceous Basin. There was no previous research based on method of the sequence stratigraphy and correlation well-logs. I made 13 measured sedimentological cross-sections that were correlated to stratigraphical cross section along depositional dip and strike. Structures of the Upper Turonian sandstones (genetic sequences TUR 5 - 7) are dominated by trough cross bedding that migrate on a slightly inclined delta slope (1 - 5ř). The main direction of paleocurrents is towards SE or E. The analysis of thicknesses of parasequences (for TUR 4 - TUR 7) gives trend of thinning parasequences through time. Increasing content of the potassium is evident within sequences TUR 4 to TUR 7. It is independent on the grain-size, but indicates rapid transport from the source area.
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Brachiopoda and polychaeta in Taphocenoses of the Bohemian Cretaceous Basis
Sklenář, Jan ; Košťák, Martin (advisor) ; Michalík, Jozef (referee) ; Vašíček, Zdeněk (referee)
The sesile suspension feeders of Brachiopoda and Polychaeta phyla are relatively well represented in the Bohemian Cretaceous Basin (BCB), and show significant diversity. All three subphyla of Brachiopoda (Linguliformea, Craniiformea and Rhynchonelliformea) are present in the fossil record of the sedimentary basin infill; from Polychaeta, there has hith- erto been evidence of only the Canalipalpata subclass members that created solid, usually carbonatic tubes. In both abundancy and diversity, the most richest associations of fossil brachiopods and polychaets occure in near-shore facies of the Cenomanian to the Lower Turonian, and hemipelagic facies of the Late Turonian age. Prior research, as shows the literature survey given by the author, has been focused mainly on representatives of both groups of near-shore facies origin. The aim of this thesis is to fill in the existing gaps in our understanding of these groups within the BCB. This objective is accomplished in the form of a series of studies (Sklenář & Simon 2009, Vodrážka & al. 2009, Sklenář & al., in press) elaborating the following topics in detail: (A) taxonomy, distribution, morphology, variabil- ity, evolutionary relationships and stratigraphic significance of cancellothyrid brachiopod Gyrosoria abundant in the Middle and particularly in...
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The potential of karst conduits development in the area between the Úštěcký and Košátecký stream basins and the delimitation of the catchment areas of the main spring groups
Pátek, Karel ; Bruthans, Jiří (advisor) ; Kůrková, Iva (referee)
The main objective of the work was to determine the extent to which the rocks forming the outcrops in the area between the Úštěcký and Košátecký Creek basins are subject to decay and karstification. This was studied by means of acid leaching. The study area contains some of the most important groundwater reserves in the Czech Republic and understanding the local conditions is crucial for proper groundwater management. Samples were collected from exposed rock outcrops in the vicinity of Košátecký Creek and the soluble component (calcite content), degree of disintegration, rock density and porosity were determined by leaching the samples in 10% HCl solution. In general, it was observed that at a low calcite content, the degree of disintegration of the samples during leaching was low, but the porosity of the samples increased. When calcite content exceeded 40%, most samples started to disintegrate at least from 50%. The results showed that there are layers with a high calcite content and high disintegration degree in the study area, which may host karst preferential pathways. Such layers are thin and embedded in thick layers of quartz sandstone. In the second part of the work, the distribution of hydrogeological basins was estimated on the basis of a new base flow map, measured stream flows and groundwater...
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Sytematics, palaeoecology and trophical structure of bivalve associations within the OAE2 in the Bohemian Cretaceous Basin (Upper Cenomanian): Pecínov quarry
Kunstmüllerová, Lucie
Title: Sytematics, palaeoecology and trophical structure of bivalve associations within the OAE2 in the Bohemian Cretaceous Basin (Upper Cenomanian): Pecínov quarry Author: Bc. Lucie Kunstmüllerová Department: Institute of geology and palaeontology Supervisor: doc. RNDr. Martin Košťák, Ph.D. Abstract: This master thesis provides an updated taxonomic inventory of the bivalve fauna of the Pecínov locality, places the fauna in its palaeobiogeographic setting, and addresses its palaeoecological significance. In the literature research part of the thesis the basic geology of the locality and an overview of the Bohemian Cretaceous Basin are presented. Processes connected to the ocean anoxic events, specifically to the OAE 2 are also discussed. The research part of the thesis describes the systematics of the bivalve assemblage (with the exception of Inoceramidae) and its statistical evaluation with the emphasis on the environment interpretations of the locality. In total, over 350 specimens have been considered and assigned to 20 genera within 15 families and 9 orders. Bivalve functional morphology and guilds are described to interpret palaeoecology. Guilds are based on life habit and feeding category. Four main guilds are recognized: epifaunal suspension-feeders, semi-infaunal suspension-feeders, infaunal...
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Short-term cyclic paleoenvironmental variations in Middle Turonian hemipelagic deposits, Bohemian Cretaceous Basin
Voženílková, Kristýna ; Uličný, David (advisor) ; Chadimová, Leona (referee)
The sedimentary record of the Turonian substage (Upper Cretaceous) offers an opportunity to examine climatic variations in a time of peak greenhouse climate. In the Bohemian Cretaceous Basin, recent cyclostratigraphic studies examined the cyclic variations of sedimentary environments of the Lower and Upper Turonian, while the cyclostratigraphy of the Middle Turonian substage has remained less understood. This thesis applied methods of spectral analysis to well logs and elemental composition data from several boreholes located in the central part of the Bohemian Cretaceous Basin, in order to better understand the environmental variations of the Middle Turonian substage and their possible astronomical forcing. A short eccentricity (~100 kyr) signature has been found in well log data, as well as the carbonate content of the Bch-1 borehole section and correlated over more than 20 km within the study area. Biogenic carbonate production is considered to be the cause of astronomically controlled cyclicity in content of Ca (proxy for CaCO3). For most of the substage, the carbonate cyclicity was shown to be decoupled from clastic sediment input variations, except the basal part of the Middle Turonian succession where clastic proxies are in phase with carbonate variations. It is proposed that the...
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Surface and ground water of the Libický floodplain forest
Bašta Spinali, Izabela ; Weiss, Tomáš (advisor) ; Slavík, Martin (referee)
In the Quaternary, the area of the Libický floodplain forest was shaped mostly by the action of the Elbe river. The river generated a structure of oxbow lakes, pools, wetlands, floodplain forests or wet grasslands. These are connected by shallow groundwater of the Quaternary aquifer. During the Upper Cretaceous period, the area of Libický forest was flooded by the sea, which resulted in the formation of the bedrock of Libický forest - now the Cenomanian aquifer of the Poděbrady mineral spring structure. This aquifer is part of the Bohemian Cretaceous Basin. This thesis provides an overview about the waters in the area of the Libický forest, especially about: the development of the structures of surface water during the last ~2k years, groundwater of the quaternary aquifer and mineral water of the Poděbrady mineral spring structure. Finally, this thesis contextualizes this knowledge into climatic, geological, pedologic and also to ecological conditions of the area of Libický luh which is an important ecosystem in terms of biodiversity in otherwise relatively densely populated agricultural landscape. Key words: Libický luh, surface water, hydrology, Elbe, groundwater, hydrogeology, Cenomanian aquifer, Bohemian Cretaceous Basin, Poděbrady mineral spring structure, floodplain forest
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Crustacea (Decapoda, Cirripedia) from the Bohemian Cretaceous Basin
Kočová Veselská, Martina ; Košťák, Martin (advisor) ; Krobicki, Michal (referee) ; Schweigert, Guenter (referee)
This thesis deals with systematic revision, evolutionary trends, palaeoecology and migration patterns of crustaceans (Cirripedia and Decapoda) from the Upper Cretaceous of the Bohemian Cretaceous Basin. Thesis is presented as a compilation of 9 papers that were published in scientific peer-reviewed journals and includes not only old museum material, but also numerous crustacean specimens which have been recovered in the last decade. Besides, short remarks on fossil crustaceans currently under study or in the process of being published (Paraclythia, Oncopareia, Acrothoracica) are also included in this thesis. In view of the fact that the fossil crustaceans from the BCB were most recently recorded in the turn of the 19th and the 20th centuries (and partially revised in the first half of the 20th century) and since the systematics and taxonomy have changed significantly, all papers presented here focus primarily on systematic revision and modern description. The essential part of the thesis thus deals with taphonomy and its bearing on the identification of fossil material. Thanks to a modern description, new species of Ctenocheles fritschi (axiidean shrimp), Archaeochionelasmus nekvasilovae (acorn barnacle), Myolepas reussi and Capitulum sklenari (pedunculate barnacles) were erected. C. fritschi is...
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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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Foraminifera of the Bohemian Cretaceous Basin
Hašková, Barbora ; Holcová, Katarína (advisor) ; Frank, Jiří (referee)
The thesis deals in the compilation part with systematic classification, biology, morphology of the test, ecology and palaeoecology of the Foraminifera. Next research focuses on the history of Cretaceous Foraminifera in our area and the geology of the Bohemian Cretaceous Basin, focusing on Úpohlavy site in the northwestern part of the Bohemian Cretaceous Basin. Three samples from Úpohlavy section were preliminary micropaleontologically analysed. Plankton / bentos ratio was counted. Genus Heterohelix and Planoheterohelix was described and taxonomically studied. Keywords: Upper Cretaceous, Bohemian Cretaceous Basin, Foraminifera, Heterohelix 1
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Upper Turonian and lower Coniacian calcareous nannoplankton stratigraphy in the borehole V 800 Střeleč, Bohemian Cretaceous Basin
Svobodová, Andrea ; Švábenická, Lilian (advisor) ; Ozdínová, Silvia (referee)
Upper Turonian and Lower Coniacian calcareous nannoplankton stratigraphy in the borehole V 800 Střeleč, Bohemian Cretaceous Basin Number of biostratigraphic studies has been performed within the Upper Cretaceous platform sediments of the NW Europe, however, the problem of Turonian-Coniacan boundary has not yet been satisfactorily resolved using available methods in the field of micropaleontology. The proposed thesis has described the species composition of calcareous nannoplankton assemblages in the Bohemian Cretaceous Basin, across the Upper Turonian- Lower Coniacian interval, focusing on the stratigraphically and paleoecologically important species. Seventy-three taxa of calcareous nannofossils in the studied material have been determined and signifiant species have been discussed (Marthasterites furcatus, Kamptnerius magnificus, Lucianorhabdus sp., Braarudosphaera sp., Nannoconus sp., Watznaueria barnesae, Uniplanarius gothicus, Quadrum gartneri, Thoracosphaera operculata). For purposes of this thesis, a suitable material from the V 800 Střeleč borehole, one of the key cretaceous profil in the Český ráj area, was obtained.
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