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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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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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The Identification and the Origin of the Gemstones Adorning the Insignia of the Charles University in Prague , the Faculty of Science
Petrová, Zdeňka ; Goliáš, Viktor (advisor) ; Hanusová, Irena (referee)
The issue of a sceptre for the newly founded Faculty of Science was first discussed on the meeting of Faculty professors on the 25th November 1921, more than a year after the separation of the Faculty of Science from the Faculty of Arts. The commission elected from among the professors proposed a motion that the new Faculty sceptre should resemble the sceptre of the parental Faculty of Arts. Through a mediation of the Ministry of Education and National Enlightment the design of the new sceptre was ordered from the Academy of Arts, Architecture and Design and it was elaborated by prof. Jaroslav Horejc. However, in January 1923, his design was rejected, because it didn't meet the requirements of the professors' conservative approach. When prof. Horejc refused to make a modified copy of the sceptre of the Faculty of Arts, the professors addressed Tengler, the goldsmith who had made the sceptres of other faculties and of the rector in previous years. Alois Tengler was willing to make a modified copy of the sceptre of Faculty of Arts, but he also proposed a new design (with estimated price of 20 000 K), which the professors found more suitable and subsequently this design was adopted. Tengler committed himself to manufacture the sceptre by the 15th November 1924 and to incorporate any additional design...
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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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Uranium mineralisation of the Lugian orthogneiss as a precursor of the radioactive springs genesis
Fatková, Karolína ; Goliáš, Viktor (advisor) ; Škoda, Radek (referee)
The Lugian area is known for the occurrence of springs of radioactive radon mineral waters in areas formed by orthogneisses. Samples of mineralized orthogneisses (Sněžník, Krkonoše and Jizera) found by field radiometry were examined. By the laboratory gamma spectrometry of 28 samples, it was discovered that K and Th have background concentrations, in contrast U-Ra is increased up to 108,5 ppm. The distribution of radionuclides was determined by the alpha autoradiography method in eight selected samples with the highest uranium concentrations. According to optical and electron microscopy with ED analysis, radionuclides are present in the following mineralization stages: Common accessory minerals (zircon, monazite, xenotime, apatite, thorite) occur in the primary magmatic association. The primary magmatic uraninite s.s., associated with zircon, was found in two samples. Its presence is probably the main reason for the high fertility of lugian orthogneisses. Uraninite s.s. also occurs in the form of inclusions in pyrite in the metamorphic (syndeformative) period. Symptoms of greisenization (fluorite, fluorine-rich zircon) can be observed in the Jizera orthogneiss. The hydrothermal stage with comb-like quartz and hematite in the cavities and veinlets is evident in the Krkonoše orthogneiss. The...
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Radioactive medicinal springs in the Skalná - Bad Brambach area
Turnová, Štěpánka ; Goliáš, Viktor (advisor) ; Vylita, Tomáš (referee)
Radiohydrochemical exploration took place in east part of the "smrčinský" pluton between "Skalná-Plesná-Bad Brambach in years 2016-2018. The main aim of the exploration was location and thorough research of possible occurrence of waters with radioactive concretation higher than 1500 Bq/l. That is a value for radioactive mineral waters given by the "lázeňským" law number 164/2001 Sb. Most important area is Plesná-south where was discovered several springs with values exceeding 5000 Bq/l. Eminent spring is called "Břetislav-Radonka" and lies one kilometre southwest from the train station Plesná-Šneky with an activity of about 12.5 kBq / l 222 Rn and a flow rate of about 2.5 l / min. It is the most active surface discharge of radon mineral water in the Czech Republic Another significant source area is north of Skalna - north. These springs were discovered almost 60 years ago, Dr. Marie Zukriegelová. The main source of this area was named after its discoverer - the "Marie Z" spring with an activity of 5800 Bq / l 222 Rn.Further the research focused on historical radioactive conduit which were used to supply village Skalné with water. The conduit was separated on two "branches" and the younger one was built ten years after the first one. In both pipes were found radioactive waters and the most important...
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