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Radioactive accessory minerals in granitoids and its changes during metamorphosis and alteration.
Tuhý, Marek ; Goliáš, Viktor (advisor) ; Matějka, Dobroslav (referee)
This paper is focused on gathering information about alterations of radioactive accessory minerals in granitic rocks. These minerals become unstable during the influence of fluids and increased temperature and pressure conditions. Allanite is usually metamict therefore it is more easily altered than others. Alteration of monazite is described as decomposing original grains which leads to the formation of secondary minerals such as allanite, apatite, minerals of thorium and epidote. Zircon is the most durable mineral mentioned in this paper. Zircon is altered mainly if it is metamict. Majority of authors agree that during alteration uranium is mobilized into fluids and thorium with REE is incorporate into the secondary minerals.
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Contamination of foodplain of the Ploučnice river by heavy metals: relation to its architecture
Hošek, Michal ; Goliáš, Viktor (advisor) ; Kříbek, Bohdan (referee)
Summary: This thesis is focused on mapping of contaminants released into the environment probably due to uranium mining. These chemical contaminants are used to reconstruct the sedimentary processes. In the thesis we evaluate geochemical situation in the catchment area in the locality Borecek (part of the municipality Ralsko) using the overbank sediments as sedimentary archives of pollution during the last decades by elements U, Ba, Zn, Ni and 226 Ra. A map of aerial survey of gamma activity was used to select the area of interest, for more accurate localisation we used a surface gamma spectrometry. On Borecek we retrieved ten depth profiles of alluvial sediments (up to 230 cm) and one in Mimon, all samples were subjected to X-ray fluorescence spectral analysis (XRF), across the floodplain we performed gamma wire logs. For interpretations of floodplains architecture electrical resistivity tomography (ERT) was used and selected profiles were analysed for the activity of 226 Ra and 210 Pb. Interrelation of 226 Ra and Ba proved that radiobarite is the main source of the gamma activity. 210 Pb / 226 Ra ratio was used as sediment age indicator. With enrichment factor (LEF), we performed chemostratigraphic correlation of the sediments, for that the concentration of the target elements is corrected for varying...
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Springs of the radioactive medicinal water in the Lázně Libverda - Świeradów-Zdrój area
Hrušková, Lenka ; Goliáš, Viktor (advisor) ; Vylita, Tomáš (referee)
The main radionuclide causing high water radiation is 222 Rn with half-life 3.82 days. Concentrations of radon in radioactive mineral water in the Krkonoše-Jizera Crystalline Complex are very high and do not correspond with the concentration of uranium in the source rocks. These springs probably well up near the uranium mineralisation. Search for radioactive mineral water started in 2005 in Orlice- Sněžník Dome built by orthogneisses, which was the first promising area for such research. The research continued to the areas of Jánské Lázně and Horní Malá Úpa built by the Krkonoše orthogneisses in the next few years. In the last two years research was conducted in Lázně Libverda. Until then there were only a few known springs with radioactive mineral water. Lázně Libverda-Świeradów-Zdrój area is located in the Krkonoše-Jizera Crystalline Complex built by Cambrian/Ordovician orthogneisses and Variscan granite pluton. Jizera orthogneisses and the contact of these two objects were considered to be very promising in terms of finding springs of the radioactive medicinal water. Another criterion for a successful exploration is also an abnormal tectonic deformation of the zone. Uranium exploration was also conducted in 1950s, so we could use data available from the emanatory survey on a scale of 1:5000 and...
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The 234U/238U isotope ratio in waters near the uranium mineral deposits
Fanta, Martin ; Goliáš, Viktor (advisor) ; Strnad, Ladislav (referee)
Uranium has three natural isotopes: 238 U, 235 U and 234 U. Isotopes 238 U and 235 U are primordial, isotope 234 U is one of the daughter products of 238 U decay series. Genetically dependent uranium isotopes 238 and 234 are fractionated in nature. The main reason is the alpha recoil in solid (crystalline) phase, where there is a preferential settling subsidiary 234 U in a higher oxidation state (VI). The isotope 234 U is then more available at the recent geochemical processes: leaching and alteration. Water then usually has 234 U/238 U activity ratio higher than 1, while the activity ratio in solid residuum is smaller than unity. Isotopic ratio in water is dependent on many factors. The most important are the nature of source rocks, weathering rate, the dynamics of geochemical processes (e.g. fluid-flow velocity) or anthropogenic influence on geological environment at mining of uranium deposits. Identification of these fractionation factors is not easy. Differences in the isotope ratios in water may be used to identify the source of uranium and to evaluate the contribution of technogenic uranium.
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SIlver binding at the polymetallic deposits of Blanice furrow and comparison with similar deposits in the world
Kuchyňová, Markéta ; Zachariáš, Jiří (advisor) ; Goliáš, Viktor (referee)
Blanice Furrow is about 200 km long fault system which extends from Český Brod to basin of Danube in Austria. Ore mineralization is tied to rupture structure of Blanice Furrow. Predominant polymetallic Ag-Pb-Zn±Cu mineralization occurs along entire length of Blanice Furrow. Other important type of mineralization is gold mineralization (Roudný deposit, Dobrá Voda deposit) and uranium mineralization (Okrouhlá Radouň deposit). Historical medieval silver mining districts are Stříbrná Skalice-Střímělice, Ratibořické Hory-Stará Vožice and Rudolfov. This paper describes geology and mineralogy of silver- deposit in Blanice Furrow and comparisom of Blanice Furrow with different types of hydrothermal Ag- deposits such as Ag-Ni-Co-Bi-As deposit or Mississippi Valley type. In Blanice furrow the silver isn't bound to galena and sphalerite as we would expect, but to Ag-tetrahedrite and other silver-bearing minerals. Silver from tetrahedrite is a product of retrograde exchange reaction, which was in progress during cooling in solid state . Ag-values of tetrahedrite and Ag-Sb-S phases can be used it as mineral thermometer. Mineral thermometer can help us to define temperature durinng formation of mineralization, in case of Blanice Furrow the temperature is defined between 200 and 300 řC. Powered by TCPDF (www.tcpdf.org)
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Sulphidic mineralization in the vicinity of the Bílina fault
Markes, Jan ; Zachariáš, Jiří (advisor) ; Goliáš, Viktor (referee)
The neoidic sulphide mineralization located in tertiary sediments of Lom Bílina in Bílina's fault is of hydrothermal origin. The sulphidic mineralization is associated with fault systems of Eger rift and temperature of fluid crystallization was about 50řC. The mineralization of Bílina's fault is rather monotonous, the marcasite and pyrite is mostly found without a trace elements. In the crystals were also registered zones with the contents of trace elements, especially As and Ni. The contents of As enriched precipitation zones were fluctuating from 0,2 to 5,4 wt. %, Ni enriched zones were ranged from 1,6 to 5,9 wt. %. The precipitation zones with increased As and Ni content were very thin, there were very short time intervals of As and Ni enriched fluids precipitation. In the marcasite crystals were also found the porous zones of clay mineral microinclusions. These zones showed higher content of Al and Si. There is high abundance of Fe-disulfides at Bílina's fault-dispersed in coal bed, or bonded to tectonic zone of the Bílina's fault. Pyrite and marcasite are dispersed in the coal bed and genetially aren't related to sulphides bonded to Bílina's fault.
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Radioactivity of building materials
Kocíková, Pavla ; Goliáš, Viktor (advisor) ; Třískala, Zdeněk (referee)
The work examines the issue of radioactivity of construction materials. The introduction deals with the approach to radioactivity from the general and legislative points of view and its origin and division. It briefly mentions units of activity. It further deals with the issue of radioactivity in construction materials as such, the issue of emerging radon and emanation of construction materials. The second part of the work focuses on extreme cases of use of unsuitable construction raw materials in the building industry in the history of the Czech Republic, specifically houses in Jáchymov, aerated concrete produced in Poříčí near Trutnov and prefabricated houses START. The closing part deals with the system of evaluation of natural radionuclide content in construction materials under the applicable legislation and it briefly describes the procedure of manufacturers and importers of construction materials in case of exceeding limit values.
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The vitrification methods used for the high active waste from spent nuclear fuel reprocessing.
Machová, Pavlína ; Goliáš, Viktor (advisor) ; Jelínek, Emil (referee)
This thesis summarizes the general concepts regarding the High-level waste vitrification. It describes the one-stage and two-stage principles of vitrification and special method "cold crucible". There are summarized advantages and disadvantages of these methods. In this thesis are specific of vitrification facilities around the world. There are the general characteristics of glass used for immobilization High- level waste. Most countries use borosilicate glass, but only in Russia are used phosphate glass. There is shown the composition range of glass and compare their typical properties. This thesis ends with an example of the chemical composition of certain ending vitrification products.
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Radioactivity of granitoids of the Krkonoše-Jizera pluton
Černík, Tomáš ; Goliáš, Viktor (advisor) ; Matolín, Milan (referee)
2. SUMMARY This thesis is focused on the natural radioactivity of the Krkonoše pluton, which is divided in 6 particular types of granite: the Jizera, the Liberec, the Fojtka, the Tanvald, the Harrachov, the Krkonoše ones. The goal of the thesis was to compare these values and find out whether there was an unlike element (U, Th, K) content difference. Based on literature data about the Czech and Polish part of pluton, there was assigned data of the analysed samples (of contents of K, U, Th) to each type of granite. The literature data was refined on the base of the current knowledge. The localized collection points were assigned to the particular types of the Krkonoše - Jizera granitoids. The analytic data collection was statistically evaluated. On the base of the statistic data evaluation significant differences of the radioactive element content of the particular types of granite was proved. The most radioactive one is the Harrachov granite. The Tanvald one has a distinctively anomalous ratio of U to Th higher than 1. The other types of granite have only an average level of radioactivity. There was also checked a significant aerial gamaspectrometric anomaly in the south - west direction of Hejnice. There was made a field gamaspectrometric measurement, which did not prove the significant increase in an...
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