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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Trojrozměrná tomografie Českého masivu ze seismického šumu / Three-dimensional ambient noise tomography of the Bohemian Massif

Valentová, Ľubica January 2018 (has links)
We have performed 3D ambient noise tomography of the Bohemian Massif. We invert adopted inter-station dispersion curves of both Love and Rayleigh waves in periods 4-20 s, which were extracted from ambient noise cross-correlations, using a two-step approach. In the first step, the inter-station dispersion curves are localized for each period into the so-called dispersion maps. To account for finite-frequency effects, gradient method employing Fréchet kernels is used. Assuming membrane wave approximation of the surface wave propagation at each period, the kernels were calculated using the adjoint method. To reduce the effect of data noise, the kernels were regularized by Gaussian smoothing. The proper level of regularization is assessed on synthetic tests. In the second step, the phase-velocity dispersion maps are inverted into a 3D S-wave velocity model using the Bayesian approach. The posterior probability density function describing the solution is sampled by more than one million models obtained by Monte-Carlo approach (parallel tempering). The calculated variance of the model shows that the well resolved part corresponds to the upper crust (i.e., upper 20 km). The mean velocity model contains mainly large scale structures that show good correlation with the main geologic domains of the Bohemian...
102

Minerální a chemické změny během krystalizace magmatu a tvorby pozdně variských intruzí a žil v moldanubické zóně Českého masívu / Mineral and chemical changes of magma crystallization during formation of post-Variscan intrusions and veins in the Moldanubian Zone of the Bohemian Massif

Kubínová, Šárka January 2019 (has links)
- 1 - English abstract The late-Variscan magnesium-rich potassic to ultrapotassic igneous rocks create numerous dykes, dyke swarms and several plutonic bodies at the boundary between the Moldanubian Zone and the Teplá-Barrandian Block of the Bohemian Massif. They represent a volumetrically smaller group of igneous rock but they are the key to understand generation of melt and processes of mantle metasomatism and shallow-level magma differentiation. In addition, they are considered as an indicator of the tectonic evolution of this part of the Bohemian Massif during the final stages of the Variscan orogenesis. Currently, they are the subject of discussion by several authors in terms of their genesis, emplacement time and geodynamic significance. The presented thesis is a compilation of four scientific publications that are aimed at the petrological study of selected (ultra)-potassic dyke rocks from several localities at the western border of the Moldanubian Zone. The study of mineral textures, mineral chemistry and whole-rock geochemistry together with magnetic fabrics, structural field relations and age determinations allowed us to describe the crystallization history of these rocks, discuss their evolution from melt generation to magma ascent and emplacement, and form the model of sequence of Variscan...
103

Rudistová společenstva svrchní křídy ve výplních kapes teplického ryolitu - systematika, paleoekologie, stratigrafie / Rudist assemblages of the Upper Cretaceous "pocket" infills in the Teplice rhyolite - systeamtics, palaeoecology, stratigraphy

Křížová, Barbora January 2018 (has links)
The study (MS, diploma thesis) is based on more than 1500 rudist samples from the Upper Cretaceous sediments of localities Písečný vrch and Na Stínadlech (near Teplice). Investigated samples come mainly from the collection of A. H. Fassel and were collected at the end of the 19th century, currently stored in the Regional museum in Teplice and National museum in Prague. The rudist shells were determined by generic and species levels, including five genera and eight species. The stratigraphic age of both localities has been a subject of discussion since the second half of the 19th century. In the recent decades, the opinion on the lower turonian age prevailed. However, five of the eight species present in the studied localities demonstrate the upper cenomanian age of the assemblages, making them probably the oldest known rudist-corals assemblages of its kind. The palaeoecological analysis and the ecological relationships proposal for the studied localities is based on the research in literature on palaeoecology and evolution of the rudists, also presented in the study. Key words: Bohemian Cretaceous Basin, Cenomanian - Turonian, rudists, corals, palaeoenvironment, Teplice rhyolite
104

Přínos Tschammerovy knihovny v Těšíně pro retrospektivní národní bibliografii / Contribution of The Tschammer Library in Cieszyn for Retrospective National Bibliography

Šícha, Vojtěch January 2019 (has links)
The subject of my thesis is the bibliographic processing of the collection of old Czech prints published until 1800 preserved in the Tschammer Library in Cieszyn. The aim is a compilation of bibliographical inventory of preserved editions to give an answer to three research questions. First question is: can a revision of former research results bring something new from the perspective of the national retrospective bibliography? Than whether and how the results of the analysis of the Czech historical collection of specifically local church library can extend the existing knowledge in the research of the history of book culture in Bohemia, Moravia and Silesia? Finally, what does the analysis of the provenance of preserved copies held in the Tschammer Library bring to the history of readers, reading and book culture in the Czech lands? The introductory chapter is devoted to the development of evangelical community of Cieszyn Silesia from the 16th to the beginning of the 19th century. The second chapter presents the history of the library and the basic characteristics of its historical collections. The third chapter focuses on the results of my bibliographic research. The conclusion brings a summary of the work and an evaluation of the achieved results, followed by a bibliographic inventory of...
105

Mechanismy vmístění a magnetické stavby žil syenitových porfyrů (západní části Moldanubika) / Emplacement and magnetic fabrics in dikes of syenite porphyries (Western Moldanubian Zone)

Orságová, Lucie January 2010 (has links)
ENGLISH ABSTRACT We present new results of structural and magnetic (AMS) analyses of selected dikes of melasyenite, quartz melasyenite to melagranite porphyries accompanied by lamprophyres (minettes). The studied dike from the locality Nihošovice were dated by U-Pb method on zircons at 338 Ma. The asymmetric structural pattern of the studied dikes gives an excellent evidence for their emplacement and orientation of magmatic flow. The studied dikes were emplaced into: (i) Prevailing parts of the Central Bohemian Plutonic Complex (locality Malčice) and (ii) host high-grade metamorphic rocks of western part of the Moldanubian Zone (locality Nihošovice). Despite of the extensive area of occurrence, compositional variations and age of emplacement of these dikes are relatively narrow. Their geochemical and petrological compositions broadly correspond to ultrapotassic plutonic rocks (durbachites). The dikes are steeply dipping in trend ~NNW-SSE to ~W-E, with range in width between ~20 and ~25 meters. In general, our results show: (i) A relatively low degree of magnetic anisotropy (P= 1.012 - 1.152); (ii) Mostly oblate (planar) fabric, especially in marginal parts of the intrusive bodies (T= -0.091 - 0.941); (iii) Evidence for subhorizontal magmatic flow trajectory defined for a newtonian magma with typical...
106

Zatápění dolu Hamr I a posouzení vlivu geologické stavby území na hydrogeologické poměry v severovýchodní části strážského bloku / 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 January 2011 (has links)
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....
107

Teleseismická tomografie svrchního pláště pod Českým masívem / Teleseismic Tomography of the Upper Mantle beneath the Bohemian Massif

Karousová, Hana January 2014 (has links)
Passive seismic experiments, MOSAIC, BOHEMA I-III, EgerRift, or, PASSEQ, carried out in the region of the Bohemian Massif (BM), allowed a detailed study of velocity structure of the upper mantle. We present results of tomography studies of the upper mantle beneath the north-eastern and southern parts of the BM based on the data from the BOHEMA II and BOHEMA III experiments (2004-2006). Despite the fact that regions with the highest resolution of velocity perturbations differ in the models, tomography images are similar in overlapping parts. Models of the upper mantle show mostly low- velocity perturbations relatively to radially symmetric velocity model of the Earth beneath the BM. Limited high-velocity heterogeneity beneath the Moldanubian unit, extended in the NE-SW direction, reflects thickening of the lithosphere due to a collision of the BM with the Brunovistulian micro-plate during the Variscan orogeny. The tomography based on the data from the BOHEMA III experiment revealed significant high-velocity heterogeneity in the southern margin of the model with a subduction of the lithosphere beneath the Eastern Alps. Tomographic tests showed that effects of uncorrected velocity heterogeneities within the crust can appear as deep as 100 km and, therefore, they could lead to erroneous interpretation of...
108

Studium horninových struktur v Českém ráji pomocí seismického šumu / Ambient noise investigation of rock structures in Bohemian Paradise

Müller, Jozef January 2021 (has links)
We carry out non-invasive ambient noise investigation of rock structures in Bohemian Paradise (Bohemian Cretaceous Basin, Czech Republic). The study is focused on two key topics: 1) An in-situ elastic moduli estimate of competent, horizontally deposited sandstone layers. This is done by performing an ambient noise array measurement. The recording is processed with f-k array analysis, from which frequency-dependent Love and Rayleigh wave dispersion curves as well as the Rayleigh wave ellipticity are retrieved. The data are inverted for P- and S-wave velocity profiles, from which the Young's and shear modulus are successfully estimated. 2) Study of local response of Kapelník rock tower. We analyse a dataset of ambient noise recordings from the top of the tower and from its foot. Information about tower oscillation frequencies and directions, together with amplification ratios, are retrieved from particle motion polarisation analysis and from site-to-reference spectral ratios. The Euler-Bernoulli beam theory is finally used to interpret the measured data using the elastic moduli estimated from the noise array measurement. Keywords: Bohemian Paradise, rock tower, seismic ambient noise, seismic surface waves
109

Longing to belong: musical practices in the expulsion of the Germans from the Bohemian lands

Präger, Ulrike Christa 22 January 2016 (has links)
In 1945/46, after the surrender of Germany in the Second World War, approximately twelve million German civilians living in Central and Eastern Europe were expelled (or fled before they received the inevitable expulsion order) mostly to Germany in what R.M. Douglas termed the "largest forced population transfer [...] in human history." Even though these events occurred over sixty years ago, the recollections of these expellees suggest the ongoing immediacy of their experiences. For this phenomenological-historical ethnography, I collected more than eighty life stories and oral histories specifically from ethnic Germans expelled from Bohemia, Moravia, and Czech Silesia (Sudeten Germans). Through the lenses of musical practice and musical repertoire, I investigate how these Sudeten Germans used and still continue to use music as a tool for both remembrance and adaptation in their new environments. I seek to understand music's significances for social and political integration in the Sudeten-Germans' "new sounding homeland" in West Germany. Taken one at a time, these recollections disclose the various ways in which music and musical practices retrieve memories of their Bohemian homelands and are able to mitigate both the loss of those homelands and the distressing overall effects of expulsion. Woven together, these recollections reveal how music offers emotional solace and facilitates the building of a new sense of belonging in the face of geographic displacement and material dispossession. I then compare these recollections to memories of Sudeten Germans expelled to the former East Germany as well as to the memories of Germans who were forced to stay in Czechoslovakia. This comparison highlights how the reframing and even silencing of musical practices in these environments affected processes of social identity reconstruction until the 1989 Velvet Revolution. I suggest that the analysis of the Sudeten Germans' individual musical experiences reveals new perspectives of how they used and still use musical practices to negotiate intercultural power relations and rebuild a sense of Heimat (notion of belonging to a place of origin). Broadly speaking, the results of this study facilitate an understanding of the phenomenon of forced migration and how music is able to reflect, reframe, and renegotiate it.
110

The Expatriate Experience, Self Construction, and the Flâneur in William Carlos Williams’ <i>A Voyage to Pagany</i>

Gill, Patrick W. 28 June 2007 (has links)
No description available.

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