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Role of the selenium in the late hydrothermal phase of the Příbram uranium region
Škácha, Pavel ; Goliáš, Viktor (advisor) ; Drábek, Milan (referee) ; Makovický, Emil (referee)
Příbram uranium and base-metal district is the most important vein uranium district in the Czech Republic. The main ore was represented by uraninite there and the occurrences of selenium mineralization are directly connected to it. The presence of selenides was not confirmed during the mining activities. Major development of the uranium-carbonate mineralization was found in the Bytíz deposit in the central part of the uranium district. All known occurrences of selenides have been found from this area only so far. Antimonselite, athabascaite, bellidoite (?), berzelianite, brodtkorbite, bukovite, clausthalite, dzharkenite, eskebornite, eucairite, giraudite, hakite, cadmoselite, klockmannite, naumannite, permingeatite, sabatierite, tiemannite and umangite, as well as the new unnamed selenium analogue of chalcostibite were newly identified from the dump material from the shafts No. 16 and 11A. The extremely Hg-rich hakite, which contains up to 30 wt.% of Hg, is the most remarkable mineral from the tetrahedrite group of minerals. The pertinence of the Hg-hakite was verified by means of the transmission electron microscopy. Uncommon recently formed supergene selenium association is represented by molybdomenite, munakataite and piretite. A large scale of associated minerals was found in association with...
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Dating of radioactive mineral springs of the Krkonoše-Jizera crystalline by 230Th/234U method
Fanta, Martin ; Goliáš, Viktor (advisor) ; Mizera, Jiří (referee)
The isotopes 238 U, 234 U and 230 Th, as members of the uranium-radium decay chain, are fractionated in the environment by changes of geochemical conditions, and they can be used for dating of recent or past geochemical processes in the Quaternary. Samples of water with uranium and of water-activated solids were taken of radioactive mineral water springs at two study sites in the area of Krkonoše-Jizera crystalline complex: Svatý Vojtěch (St. Adalbert) in Horní Malá Úpa, and Bukový Pramen in the Těsný důl valley in Janské Lázně. Uranium was co-precipitated in field conditions with hydroxides of FeIII+ in 50-liter water samples of the radioactive springs. In the lab, uranium and thorium were separated from water precipitates, as well as from solid samples after their chemical decomposition, using chromatographic extraction agent UTEVA. All the three isotopes of interest emit alpha particles, and so their activities were measured by alpha spectrometry and expressed as 234 U/238 U and 230 Th/234 U ratios. As an internal standard, 232 U/228 Th was used. The resulting 234 U/238 U activity ratios of four water samples measured ranged from 1.0747 to 1.423. In twelve samples of solid phases activity ratios 234 U/238 U from 0.861 to 1.129 were determined. The 230 Th/234 U activity ratios form two distinct...
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Mineral waters in the Bad Brambach - Skalná area, the current knowledges.
Turnová, Štěpánka ; Goliáš, Viktor (advisor) ; Hrkal, Zbyněk (referee)
This paper summarizes the findings of the mineral waters around Skalná - Bad Brambach. Bad Brambach are radon spa that work here since 1912. Source Wettinquelle is one of the strongest radon springs in the world. Around Skalná is anomalous quantities of uranium, however, that there occurs in such small particles that netěžitelné. Radon is a decay product of U238 series. Within the study area is also NPR Soos, who is known moffetes, but there also are so-called diatomaceous peak which is a dry salt lake containing diatoms. Area of the Nový Kostel is the area with the most frequent occurrence of earthquakes in the Czech Republic. Several earthquake swarms were recorded as well as the local populations. Recent earthquake activity has been recorded in 2011. There are also several other spa municipal Františkovy lázně, Mariánske lázně, Karlovy Vary and other radon baths, which already are but a little further, Jáchymov.
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Geological and geophysical exploration of the Kokonín fault for building constructions (Jablonec n. Nisou, Czech Republic)
Tumurkhuu, Gereltsetseg ; Goliáš, Viktor (advisor) ; Thinová, Lenka (referee)
Radioactivity is an important part of the environment. In the years 2014 - 2015 a survey on medicinal radioactive springs was carried out in the Tanvald granite body. During extensive radiohydrogeochemical exploration in the surrounding area of Schindler spring, the outcrop of U - mineralization has been found at a new construction site in the Kokonín fault. It is possible to find "hot" pieces of uranium ore fragments in the quaternary cover in this place. The occurrence of the hydrothermal (vein) type of uranium in the Krkonoše - Jizera is new as it hasn't been mentioned in literatures before. After an agreement with the owners, detailed radiometric survey proceeded in the surrounding area of two affected houses by using gamma spectrometry and emanometry at the dense net. There is a wider area between two houses with activities of 222 Rn over 1 MBq/m3 and on the ore outcrop was measured 3.3 MBq/m3 . A quaternary solifluction flow with an increased radioactivity creeps down under the House 1. The highest uranium contents reached up to 291 ppm eU (= 3 595 Bq/kg 226 Ra) on the uranium ore lens outcrop. The average of gamma dose rate is 85,6 nGy/h with maximem 261 nGy/h on the outcrop. A further radiometric survey through the entire Kokonín fault line was carried out in an area of roughly 0.25 x 1 km2...
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Springs of the radioactive mineral waters on Tanvald granite
Kohn, Pavel ; Goliáš, Viktor (advisor) ; Vylita, Tomáš (referee)
In the years 2014-2015 a radiohydrogeochemical survey was carried out in the Tanvald granite body. Tanvald granite is a two-mica granite body located on the southern edge of the Krkonoše-Jizera Pluton, in the Lusatian part of the Saxony and Thuringian zone of the Variscan orogenic belt. The aim of the survey was to find radioactive water, the 222 Rn volume activity of which exceeds 1500 Bq/l. Such water is - under the Act no. 164/2001 Coll. - considered as radioactive mineral water. The result was a found of 20 water sources meeting this condition and many other sources approaching this value. In terms of the findings, the most important area is Dlouhý Most, where 8 of the radioactive water resources exceeding 1500 Bq/l were found. The most important of these is probably the source TGR/11 with the 222 Rn volume activity 2449 Bq/l. A cluster of water sources with a slightly higher conductivity (exceeding 300 µS/cm) appears in the Dlouhý Most area. Chemical analysis of the most important of them (TG1/15) showed that it is water of the Na-Ca-Cl type, probably contaminated by a run-off from the motorway, which is salted in winter. Another important site is the Kokonín fault area. At this important geological structure a total of four springs of radioactive water with the 222 Rn volume activity greater...
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Dating of uranium secondary minerals by the Thermal ionization mass spectrometry and α-spectroscopy
Roll, Michal ; Goliáš, Viktor (advisor) ; Strnad, Ladislav (referee)
SUMMARY: This paper is focused on analytical methods, specifically on thermal ionization mass spectrometry and alpha spectrometry; both methods are often use for dating of minerals or rocks. Goal of this paper is to compare these methods and decide which one is more suitable for dating of secondary uranium minerals. Methods are completely different and we judge them closely and take into account every fact not just technical skills as accuracy or speed which are in favor of thermal ionization mass spectrometry, but also device availability, price or published researches which are in favor of alpha spectrometry. There is also suggestion that both methods can cooperate and it seems as most effective way and there is another suggestion how studies a secondary uranium minerals.
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Lead isotopes and 210 lead in recent galenas of the Lower Silesia basin
Čurda, Michal ; Goliáš, Viktor (advisor) ; Plášil, Jakub (referee)
This thesis deals with the isotopic composition of lead and 210 lead in recent galena from burning heaps after coal mining in the Lower Silesian basin. The studied sites were heaps in Radvanice, Markoušovice and Rybníček, where samples of galena, coal and burnt rocks were available. For the determination of the isotopic composition was used mass spectrometry with inductively coupled plasma (ICP - MS). Mass 210 Pb activity in galena was measured in a gamma - spectrometer Silar and the effect of radioactivity on galena crystal lattice was determined by the modified Williamson - Hall graph which was made from taken X-ray diffraction data. The values of isotope ratios in galena ranged for 207 Pb/206 Pb = 0,8402 to 0,8435 and for 208 Pb/206 Pb = 2,0663 to 2,0836. The average values of the coal were measured for 207 Pb/206 Pb = 0,8312 and 208 Pb/206 Pb = 2,0421. On the basis of these isotope ratios was found out that during the burning of coal and subsequent galena crystallization from hot gases there is no isotopic fractionation. Mass 210 Pb activity in galena ranged from 135 ± 9 Bq/g to 714 ± 22 Bq/g. Radioactivity of galena causes the developement of micro-deformation in the crystal structure. This micro-deformation is demonstrated by increased micro-strain in the crystal lattice. The level of this...
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Contamination of floodplain of the Ploucnice 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. The aim of the thesis was both the geochemical assessment of the situation in the catchment area of the Ploucnice River in Boreček using the flood sediments from the research points as sedimentary archives pollution for last decades. With depth profiles, gamma wire log, XRF and enrichment factors (LEF), we have tried to perform chemostratigraphic correlation of the sediments. As target elements U, Ba, Zn and Ni were chosen, whose concentrations are related to the grain size of the sediment. Furthermore, the theory of secondary pollution is developed.
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Mongolian uranium deposits
Tumurkhuu, Gereltsetseg ; Goliáš, Viktor (advisor) ; Zachariáš, Jiří (referee)
Mongolia is a landlocked country, located in northeast Asia between Russia and China. The country has a total area of 1 565 600 kmš and shares a 4 673 km long border with China on its eastern, western and southern sides and a 3 485 km long border with Russia to the north. The mining sector is the single largest industry of Mongolia, accounting for 55 % of industrial output and more than 40 % of export earnings. Prior to 1970, Mongolia was not able to develop its vast mineral resources due to a lack of infrastructure and lack of financing for mineral resource development. However, beginning in 1970, numerous deposits of copper, gold, fluorspar, uranium, and coal were developed by joint ventures formed in partnership with the Soviet Union and its allies. Increased nuclear electricity generation in Asia presents uranium suppliers such as Mongolia with an opportunity to develop its uranium and nuclear industry. This Bachelor thesis "Mongolian uranium deposits" deals with the geology and mineralogy of uranium deposits in Mongolia. It shows a current capacity of uranium reserves and possible resources and also inquiries into the future.
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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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