|
|
Palaeoecological aspects of Rhynchostreon Bayle oyster evolution
Rantuch, Jakub ; Košťák, Martin (advisor) ; Juřičková, Lucie (referee)
This paper presents a multilevel analysis of palaeoecological aspects of the process of the Rhynchostreon genera evolution. According to the latest results of research, the process of genus appears to be more dynamic than previously assumed.The processes of internal dynamics of the environment in conjuncture with other studied aspects of the late cretaceous environment (e.g. paleotemperature, salinity, etc.) were a significant factor that initiated the activity of selective pressure and represents an important factor in group evolution. In this work we provide the overall hypothesis about co-evolution of two intrageneric (sisters) lineages in Rhynchostreon genera. The definiton of evolutionary trends of intrageneric lineages within the presented hypothesis (including a new description of oyster species) is supported by various analytical methods, which anchors them in the current zoological nomenclature system. An electron microscopy, isotopes and biometrical analysis of a shell in cooperation with some of the sedimentologic methods suggest a relation of lithology (as a result of environmental aspect) and evolution process. The transregional concept of proposed ecological-evolutionary models, based on materials studies from various paleogeographic regions of cretaceous world, increases the...
|
|
|
The genesis of groundwater composition in deep basin structures on the example of the Bohemian Cretaceous Basin and the Eger Rift relationship
Dupalová, Tereza
This thesis deals with genesis of the Cretaceous thermal waters in the Ústí nad Labem. These thermal waters are interesting in that are very different from other Cretaceous thermal waters, which also appear in Benešov-Ústí aquifer system of the Bohemian Cretaceous Basin in Děčín. Thermal waters in the Ústí nad Labem area more than chalk waters resemble the thermal waters in Teplice, which are associated with body of Teplice rhyolite. Many authors studied thermal waters in the Ústí nad Labem, but isotope analysis and inverse geochemical modeling were not used for their study. Results based on water chemistry, water D and 18 O, 87 Sr/86 Sr ratios, and dissolved sulfate 34 S and 18 O values, indicate mixing of ground water from aquifers of the Bohemian Cretaceous Basin with ground water derived from crystalline rocks of the Erzgebirge Mts. Unlike thermal waters in Děčín are Ca-HCO3 type (160 mg/L), in Ústí nad Labem there are two types of thermal waters, Na-HCO3 type with higher TDS values (over 1 g/L) and Na-(Ca)-HCO3-SO4 type with lower TDS values (approximately 600 mg/L). Carbon isotope data and speciation and inverse geochemical modeling suggest a significant input of endogenous CO2 at Ústí nad Labem. Besides CO2 input, both silicate dissolution and cation exchange coupled with dissolution of...
|
|
|
The genesis of groundwater composition in deep basin structures on the example of the Bohemian Cretaceous Basin and the Eger Rift relationship
Dupalová, Tereza ; Vencelides, Zbyněk (advisor) ; Černík, Miroslav (referee) ; Buzek, František (referee)
This thesis deals with genesis of the Cretaceous thermal waters in the Ústí nad Labem. These thermal waters are interesting in that are very different from other Cretaceous thermal waters, which also appear in Benešov-Ústí aquifer system of the Bohemian Cretaceous Basin in Děčín. Thermal waters in the Ústí nad Labem area more than chalk waters resemble the thermal waters in Teplice, which are associated with body of Teplice rhyolite. Many authors studied thermal waters in the Ústí nad Labem, but isotope analysis and inverse geochemical modeling were not used for their study. Results based on water chemistry, water D and 18 O, 87 Sr/86 Sr ratios, and dissolved sulfate 34 S and 18 O values, indicate mixing of ground water from aquifers of the Bohemian Cretaceous Basin with ground water derived from crystalline rocks of the Erzgebirge Mts. Unlike thermal waters in Děčín are Ca-HCO3 type (160 mg/L), in Ústí nad Labem there are two types of thermal waters, Na-HCO3 type with higher TDS values (over 1 g/L) and Na-(Ca)-HCO3-SO4 type with lower TDS values (approximately 600 mg/L). Carbon isotope data and speciation and inverse geochemical modeling suggest a significant input of endogenous CO2 at Ústí nad Labem. Besides CO2 input, both silicate dissolution and cation exchange coupled with dissolution of...
|
|
|
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...
|
|
|
The record of sea-level changes, water circulation and sediment dispersion in the Upper Turonian hemipelagic strata of the Bohemian Cretaceous Basin
Hrnková, Magdalena ; Laurin, Jiří (advisor) ; Hladil, Jindřich (referee)
The Bohemian Cretaceous Basin was a sediment accumulation, which was deposited as an integral part of the central European epicontinental sea during the Late Cretaceous sea level highstand. It acted as a marine strait and was suited for preserving both nearshore coarse- clastic successions and hemipelagic deposits, allowing for the study of interplay between tectonics, eustatic sea level and paleoceanographic conditions. While the north-western part of the basin was extensively studied in the recent years, little information has yet been collected about the coeval along-shore environments. This thesis is aimed at bringing a new insight into these fine-grained deposits through a detailed lithological, multiproxy and time-series analysis investigation of the Late Turonian record in the Bch-1 drill core, Běchary, Czech Republic. The secular onset of carbonate-rich hemipelagic sedimentation coeval to the base of Teplice Formation is characterised by increased micrite content and changes in geochemical proxies, which are interpreted as changes in the pathway of clay distribution and silt source proximity, combined with elevated bioproductivity. Three orders of statistically significant variability were identified by time-series analysis of selected geophysical properties, two of which are carrying the...
|
|
|
Flooding of the Hamr I mine and evaluation of the geological structure impact on the hydrogeological conditions in the northeastern part of Stráž block
Rozman, David ; Datel, Josef (advisor) ; Hrkal, Zbyněk (referee)
The main objective of diploma thesis is to evaluate the impact of the geological structure on the hydrogeological conditions in the northeastern part of Stráž block. The study area in northern Bohemia is characterised by Cenomanian and Turonian sandstone aquifers, which are horizontally divided by Lower Turonian aquitard. The thesis focuses groundwater level analysis and study hydrogeological impacts of faults, neovolcanic veins and disturbances of rock environment caused by uranium mining. First part of the study presents description of general geological and hydrogeological conditions in the area with summary of previous investigations and reports. Various hydraulic interventions during mining, which have great impact on the groundwater level situation are described. Based on the data from collected boreholes, contour maps of groundwater level are prepared to study its shape and temporal changes. Hydraulic communication through aquitard and through Stráž fault zone have been examined by correlations of groundwater levels. The results of the study confirm sealing effect of Stráž fault zone in the examined section. Barrier effect of the neovolcanic veins has been confirmed on several locations and examples of increased hydraulic conductivity as the result of fault disturbances have been located....
|
|
|
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.
|
|
|
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.
|
|
|
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.
|
|
|
Radiolaria of the Bohemian Cretaceous Basin
Müllerová, Petra ; Vajskebrová, Markéta (referee) ; Holcová, Katarína (advisor)
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.
|
guest ::
