Vznik kompoziční a texturní zonálnosti mělce uložených granitoidních těles

Základním cílem této Ph.D. práce je přispět k výzkumu formování kompoziční a texturní zonál- nosti mělce uložených plutonů. Procesy vedoucí ke vzniku kompoziční zonálnosti v těchto tělesech jsou zde popisovány jak na úrovni měřítka celého magmatického tělesa (plutonu), tak z hlediska mikroměřítka. Hlavnídůrazvpodrobnějšíchčástechtétoprácejekladennakombinacirůznýchkvantitativních souborů dat ze dvou dobře vybraných plutonů (říčanský pluton ve středočeském plutonickém komplexu a melechovský pluton v moldanubickém batolitu). Detailní studie jsou podpořeny dalším výzkumem plutonů štěnovického a ševětínského a plutonu Čistá. Uvedené příklady shr- nují vývoj variského magmatismu přímo v srdci Českého masivu, od pozdního devonu do ob- dobí permu. Ph.D. práce je založena na kombinaci terénních a strukturních studií (včetně metody anizot- ropie magnetické susceptibility, AMS), texturní analýzy, petrologických, geochronologických a geochemických metod a geofyzikálních výzkumů. Dále byly navrženy a aplikovány matem- atické přístupy k interpretaci geochemických dat, s potenciálním využitím v ostatních mag- matických systémech. Pevně věřím, že tyto souhrnné studie na pečlivě vybraných příkladech mají potenciál poskyt- nout všeobecně užitečné a důkladné porozumění vzniku zonálnosti včetně mechanismů stav- by...The principal goal of this Ph.D. Thesis is to contribute to the research on formation of compo- sitional and textural zoning in shallow-level plutons. Processes responsible for emplacement of individual plutons/pulses and the origin of compositional zoning in are addressed in a great detail, from the pluton-scale down to the micro-scale. The main emphasis in the more focused part of this text is on a combination of various quanti- tative data sets from two well-selected plutons (the Říčany Pluton in the Central Bohemian Plu- tonic Complex and the Melechov Pluton in the Moldanubian Batholith). These detailed studies are supported by further research on the Štěnovice, Čistá and Ševětín plutons. In this way we cover the evolution of Variscan magmatism in the heart of Bohemian Massif in its entirety, from Late Devonian till Permian. The thesis is based on combining field and structural studies (including the anisotropy of mag- netic susceptibility, AMS), textural analysis, petrological, geochronological and geochemical methods with geophysical investigations. Mathematical approaches have been designed and applied to the interpretation of geochemical data, with potential applications to other igneous systems. I strongly believe that only such comprehensive studies on well-selected case examples have a...Ústav petrologie a strukturní geologieInstitute of Petrology and Structural GeologyPřírodovědecká fakultaFaculty of Scienc

Brand new Geochemical Data Toolkit (GCDkit 3.0) – is it worth upgrading and browsing documentation? (Yes!)

The freeware Geochemical Data Toolkit (www.gcdkit.org) is a flexible R-language package designed for handling, recalculation and plotting of whole-rock geochemical data from igneous and metamorphic rocks. The current version, GCDkit 3.0, was released in September 2011 and developed in the brand new R 2.13.0 for Windows. The release addresses some stability issues and improves the appearance of the plots. Apart from several new diagrams and plugins, it brings principal conceptual changes. The first is the internationalization – it introduces dictionaries, serving for the translation of classification diagrams. Czech and French localizations are provided as an example. Moreover, the system enables editing plates of multiple plots, in a manner previously available only for some of the stand-alone plots. Lastly, most of the commands can be invoked in batch mode, thus further speeding up otherwise tedious processing of large data files.Meskimen’s Law: There’s never time to do it right, but there’s always time to do it over

Thallium and lead variations in a contaminated peatland : a combined isotopic study from a mining/smelting area

Vertical profiles of Tl, Pb and Zn concentrations and Tl and Pb isotopic ratios in a contaminated peatland/fen (Wolbrom, Poland) were studied to address questions regarding (i) potential long-term immobility of Tl in a peat profile, and (ii) a possible link in Tl isotopic signatures between a Tl source and a peat sample. Both prerequisites are required for using peatlands as archives of atmospheric Tl deposition and Tl isotopic ratios as a source proxy. We demonstrate that Tl is an immobile element in peat with a conservative pattern synonymous to that of Pb, and in contrast to Zn. However, the peat Tl record was more affected by geogenic source(s), as inferred from the calculated element enrichments. The finding further implies that Tl was largely absent from the pre-industrial emissions (>~250 years BP). The measured variations in Tl isotopic ratios in respective peat samples suggest a consistency with anthropogenic Tl (ε205Tl between ~ -3 and 4), as well as with background Tl isotopic values in the study area (ε205Tl between ~0 and 1), in line with detected 206Pb/207Pb ratios (1.16–1.19). Therefore, we propose that peatlands can be used for monitoring trends in Tl deposition and that Tl isotopic ratios can serve to distinguish source origin(s). However, given that the studied fen has a particularly complicated geochemistry (attributed to significant environmental changes in its history), it seems that ombrotrophic peatland(s) could be better suited for this type of Tl research

The Origin of Compositional and Textural Zoning of Shallow-Level Granitoid Plutons

The principal goal of this Ph.D. Thesis is to contribute to the research on formation of compo- sitional and textural zoning in shallow-level plutons. Processes responsible for emplacement of individual plutons/pulses and the origin of compositional zoning in are addressed in a great detail, from the pluton-scale down to the micro-scale. The main emphasis in the more focused part of this text is on a combination of various quanti- tative data sets from two well-selected plutons (the Říčany Pluton in the Central Bohemian Plu- tonic Complex and the Melechov Pluton in the Moldanubian Batholith). These detailed studies are supported by further research on the Štěnovice, Čistá and Ševětín plutons. In this way we cover the evolution of Variscan magmatism in the heart of Bohemian Massif in its entirety, from Late Devonian till Permian. The thesis is based on combining field and structural studies (including the anisotropy of mag- netic susceptibility, AMS), textural analysis, petrological, geochronological and geochemical methods with geophysical investigations. Mathematical approaches have been designed and applied to the interpretation of geochemical data, with potential applications to other igneous systems. I strongly believe that only such comprehensive studies on well-selected case examples have a..

Emplacement processes and magmatic fabrics of granite diapirs: a case example of the Plechý pluton (SW Moldanubian unit, Bohemian Massif)

Oddělení geologie (zrušeno)Section of Geology (obsolete)Faculty of SciencePřírodovědecká fakult

Magnetic fabric of the Říčany granite: a record of helicoidal magmatic flow?

Oddělení geologie (zrušeno)Section of Geology (obsolete)Faculty of SciencePřírodovědecká fakult

Mechanisms of differentiation and emplacement of peraluminic granite magma: Říčany pluton, Bohemian Massif

English abstrakt This thesis is focused on emplacement mechanisms of granitic magma into upper continental crust. The studied area is the Říčany pluton due to its unusual and asymmetric shape. Therefore, it represents a suitable intrusion for interpretation different models referring to emplacement of granitic magma. Common model for ascent of magma is incremental diking in present. The Říčany pluton of the Central Bohemian Plutonic Complex is a post-tectonic elliptical shallow-level intrusion emplaced into low-grade Neoproterozoic and Lowe Carboniferous times (~337 Ma). It comprises of outer, more fractionated, strongly porphyritic granite and inner, less evolved, weakly porphyritic granite. Mesoscopic foliation represents an onion-skin pattern and corresponds well to the magnetic (AMS) foliations. Magnetic lineation has a gentle dip (0-20ř) and closely parallels with the pluton contact in its outer part whereas the lineation dips steeply (60-70ř) with a variable trend in the pluton interior. Author interprets these fabrics as a result of a helical flow, which is a faster subvertical flow in the low-viscosity pluton centre being accompanied by a subhorizontal flow in the outer, higher-viscosity (phenocryst-rich) margin. The proposed scenario of the helical magma flow can provide a viable mechanism for the..

Possibilities in presentation of geological databases in Regional Geology teaching

The thesis deals with the possibilities of presentation of geological information in the field of regional geology. The main aim of the thesis is to create the proposal of On-line Textbook in Regional Geology which can be used as a learning resource for universities, experts and all interested people. There had not been paid enough attention to the geology subject within the basic and secondary schools curriculum for last years. Geology was the part of other taught subjects. Nevertheless, there were initiatives that allowed to find new space for geology subject that has been realizing especially within frame educational programme at grammar schools. There are many resources that can be used during the educational process of regional geology such as traditional textbooks, expert compendiums, but also modern aplication in the form of internet projects. Unfortunatelly, current accesible web applications are not updated and do not include modern findings and knowledge. The proposal of On-line textbook represents the core topic of the thesis. This concept is being developed with the support of the Czech Geological Survey (CGS) in collaboration with the Faculty of Science at Charles University in Prague. There is the connection with CGS portal which is the main communication interface with the user. CGS portal..

Emplacement processes and magmatic fabrics of granite diapirs: a case example of the Plechý pluton (SW Moldanubian unit, Bohemian Massif)

Oddělení geologie (zrušeno)Section of Geology (obsolete)Faculty of SciencePřírodovědecká fakult