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Historical use of waste from the Jáchymov uranium factory as a building material
Voháňková, Michaela ; Goliáš, Viktor (advisor) ; Šálek, Ondřej (referee)
Between 1853 and 1939, colourful and highly sought-after uranium paints were produced on an industrial scale in Jáchymov. Until the discovery of radium by Marie Curie Skłodowska in 1898, the waste from production was considered essentially worthless. In the 1970s, the use of materials with increased radioactivity was detected in buildings in Jáchymov. Some of the most affected buildings were demolished. In the 1990s, remediation interventions took place during which these building materials (plaster and mortar) were removed from most of the buildings. During this period, gamma radiation doses as well as radioactivity and uranium were measured in the laboratory. The mineralogical and phase character of the material was not investigated, which was the main objective for this bachelor thesis. The presumption of preservation of at least some of the surviving houses was minimal. Nevertheless, a few unique cases have been found. A total of 11 buildings were found along a 12 km tour whose plaster showed elevated radioactivity ranging from 3.2 to 28.4 μGy/h. Sampling was carried out at 6 of them. Determination of 226 Ra mass activities was performed by laboratory gamma spectrometry, uranium contents were determined by instrumental neutron activation analysis. In the study set, the radium activities reached...
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Radon daughter products absorption by filters
Šálek, Ondřej ; Jáně, Zdeněk (advisor) ; Matolín, Milan (referee)
The work is engaged in effect of short-lived radon (222 Rn) daughter products on measurement of radon volume activity in soil gas. Solid radon daughter products 214 Po and 218 Po transform by α-decay and influence measurement of radon volume activity in soil gas. This effect was investigated by experimental measurement of radon volume activity in soil gas at the Buk radon reference site in Central Bohemia. At each particular point of radon reference site, three values of radon volume activity were determined by measuring; without filter, with automobile petrol filter and with micro-fibrous filter AFPC type. Experimental measurement demonstrates that both of applied filters have near the same effect on measured values of radon volume activity in soil gas. The difference between radon volume activity values got by measuring without filter and with filters is low, in order of measurement error. Experiment did not evidence necessity of using filter for measuring radon volume activity in soil gas. Radon volume activity measurement error is in order of several kBq.m-3 . This fact brings uncertainty into obtained results. The absence of theoretically possible high content of solid radon daughter products in soil gas samples may be explained by possible adsorption of these particles on sampling and soil...
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Well log analysis for sedimentary formation evaluation
Šálek, Ondřej ; Kobr, Miroslav (advisor) ; Lukeš, Jiří (referee)
3 ABSTRACT The work is focused on analysis of five structural well profiles penetrating sediments of the Bohemian Cretaceous Basin and the underlying Upper Palaeozoic continental basins to the crystalline basement. The objectives of well profile analysis are sedimentary formation evaluation from well log analysis and statistical analysis and evaluation of some physical properties of sedimentary rocks, which have been determined by measurements of drill cores. The aim of the work is to verify the possibility of porosity evaluation from well log analysis in the Bohemian Cretaceous Basin and the underlying Upper Palaeozoic continental basins. The next aim is to compare different geological environments with respect to physical properties of rocks. The content of the work involves presentation of well log curves, computation of porosity values and comparison between the resulting values of porosity from resistivity log, acoustic log and neutron-neutron log and from laboratory measurements of drill core samples. Data from five deep structural wells are used. Different geological environments were compared by statistical methods with respect to physical properties of rocks measured on well core samples from these five wells. Porosity evaluation from well log analysis is difficult but it is possible provided that...
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Gamma radiation of geological objects and their localization by radiometric measurement
Šálek, Ondřej ; Matolín, Milan (advisor) ; Mojzeš, Andrej (referee) ; Gnojek, Ivan (referee)
This thesis deals with gamma-ray field of size-limited uranium objects and with possibilities of their localization by a field radiometric measurement. The gamma-ray field attenuates progressively with distance from the ground source of radiation. The applied method of radiometric survey plays an important role in localization of a radioactive object. The gamma- ray field of uranium anomalous objects was studied for variable signatures of ground anomalous objects and different methods of gamma-ray survey by using mathematical modelling. The method of modelling was derived from fundamental theoretical laws describing the gamma-ray field of a point source. The verification of applied mathematical modelling was carried out by the comparison of calculated model of the gamma-ray field at three real uranium anomalous objects with experimental data of ground and mini-airborne measurement. Mini-airborne measurement was realized by the prototype of a gamma spectrometer Georadis D230A. This instrument is characterized by relatively high sensitivity compared to previously used similar devices. Airborne platform was a hexacopter Kingfischer. One of the aims of this thesis was to assess the applicability and technical capacity of D230A instrument. Calculated values of the gamma-ray field at different detection...
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Gamma radiation of geological objects and their localization by radiometric measurement
Šálek, Ondřej
This thesis deals with gamma-ray field of size-limited uranium objects and with possibilities of their localization by a field radiometric measurement. The gamma-ray field attenuates progressively with distance from the ground source of radiation. The applied method of radiometric survey plays an important role in localization of a radioactive object. The gamma- ray field of uranium anomalous objects was studied for variable signatures of ground anomalous objects and different methods of gamma-ray survey by using mathematical modelling. The method of modelling was derived from fundamental theoretical laws describing the gamma-ray field of a point source. The verification of applied mathematical modelling was carried out by the comparison of calculated model of the gamma-ray field at three real uranium anomalous objects with experimental data of ground and mini-airborne measurement. Mini-airborne measurement was realized by the prototype of a gamma spectrometer Georadis D230A. This instrument is characterized by relatively high sensitivity compared to previously used similar devices. Airborne platform was a hexacopter Kingfischer. One of the aims of this thesis was to assess the applicability and technical capacity of D230A instrument. Calculated values of the gamma-ray field at different detection...
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Gamma radiation of geological objects and their localization by radiometric measurement
Šálek, Ondřej
This thesis deals with gamma-ray field of size-limited uranium objects and with possibilities of their localization by a field radiometric measurement. The gamma-ray field attenuates progressively with distance from the ground source of radiation. The applied method of radiometric survey plays an important role in localization of a radioactive object. The gamma- ray field of uranium anomalous objects was studied for variable signatures of ground anomalous objects and different methods of gamma-ray survey by using mathematical modelling. The method of modelling was derived from fundamental theoretical laws describing the gamma-ray field of a point source. The verification of applied mathematical modelling was carried out by the comparison of calculated model of the gamma-ray field at three real uranium anomalous objects with experimental data of ground and mini-airborne measurement. Mini-airborne measurement was realized by the prototype of a gamma spectrometer Georadis D230A. This instrument is characterized by relatively high sensitivity compared to previously used similar devices. Airborne platform was a hexacopter Kingfischer. One of the aims of this thesis was to assess the applicability and technical capacity of D230A instrument. Calculated values of the gamma-ray field at different detection...
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Gamma radiation of geological objects and their localization by radiometric measurement
Šálek, Ondřej ; Matolín, Milan (advisor) ; Mojzeš, Andrej (referee) ; Gnojek, Ivan (referee)
This thesis deals with gamma-ray field of size-limited uranium objects and with possibilities of their localization by a field radiometric measurement. The gamma-ray field attenuates progressively with distance from the ground source of radiation. The applied method of radiometric survey plays an important role in localization of a radioactive object. The gamma- ray field of uranium anomalous objects was studied for variable signatures of ground anomalous objects and different methods of gamma-ray survey by using mathematical modelling. The method of modelling was derived from fundamental theoretical laws describing the gamma-ray field of a point source. The verification of applied mathematical modelling was carried out by the comparison of calculated model of the gamma-ray field at three real uranium anomalous objects with experimental data of ground and mini-airborne measurement. Mini-airborne measurement was realized by the prototype of a gamma spectrometer Georadis D230A. This instrument is characterized by relatively high sensitivity compared to previously used similar devices. Airborne platform was a hexacopter Kingfischer. One of the aims of this thesis was to assess the applicability and technical capacity of D230A instrument. Calculated values of the gamma-ray field at different detection...
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An Application of Unmanned Aerial Vehicles in Airborne Radiometry
Dědek, Jiří ; Šálek, Ondřej (advisor) ; Matolín, Milan (referee)
This thesis deals with the use of Unmanned Aerial vehicles (UAV) in radiometric survey. The main goal of this work is to review characteristics of four selected UAV and parameters of employed detectors compared to the classical airborne and ground radiometric survey. Four selected UAV were assessed, hexacopter "Kingfisher" with the detector BGO (Bi4Ge3O12) of the volume 0,2 cm3 , the octocopter "Arducopter" with the 1 cm3 CTZ (CdZnTe) detector, helicopter "Yamaha RMAXG1" with 1,8 l NaI(Tl) detector and airship "ACC15X" with 2,7 l NaI(Tl) detector. Payload capacity, detector sensitivities, flight speed, flight altitude, endurance for one charged battery or full fuel tank and wind resistance were compared among the mini- airborne instruments. The estimation of UAV radiometric data quality was derived from the sensitivity of the detectors, the flight altitude and flight speed. Estimated UAV radiometric data quality was compared to classical airborne and ground typical radiometric data quality. Three selected UAV with a certain altitude and flight speed would achieve a comparable data quality as a classical airborne survey in the altitude of 80 m and flight speed of 50 m/s. Specifically it is hexacopter "Kingfisher" with a scintillation detector D230A at altitude of 40 m and speed of 1m/s, helicopter...
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Well log analysis for sedimentary formation evaluation
Šálek, Ondřej ; Kobr, Miroslav (advisor) ; Lukeš, Jiří (referee)
3 ABSTRACT The work is focused on analysis of five structural well profiles penetrating sediments of the Bohemian Cretaceous Basin and the underlying Upper Palaeozoic continental basins to the crystalline basement. The objectives of well profile analysis are sedimentary formation evaluation from well log analysis and statistical analysis and evaluation of some physical properties of sedimentary rocks, which have been determined by measurements of drill cores. The aim of the work is to verify the possibility of porosity evaluation from well log analysis in the Bohemian Cretaceous Basin and the underlying Upper Palaeozoic continental basins. The next aim is to compare different geological environments with respect to physical properties of rocks. The content of the work involves presentation of well log curves, computation of porosity values and comparison between the resulting values of porosity from resistivity log, acoustic log and neutron-neutron log and from laboratory measurements of drill core samples. Data from five deep structural wells are used. Different geological environments were compared by statistical methods with respect to physical properties of rocks measured on well core samples from these five wells. Porosity evaluation from well log analysis is difficult but it is possible provided that...
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Radon daughter products absorption by filters
Šálek, Ondřej ; Jáně, Zdeněk (advisor) ; Matolín, Milan (referee)
The work is engaged in effect of short-lived radon (222 Rn) daughter products on measurement of radon volume activity in soil gas. Solid radon daughter products 214 Po and 218 Po transform by α-decay and influence measurement of radon volume activity in soil gas. This effect was investigated by experimental measurement of radon volume activity in soil gas at the Buk radon reference site in Central Bohemia. At each particular point of radon reference site, three values of radon volume activity were determined by measuring; without filter, with automobile petrol filter and with micro-fibrous filter AFPC type. Experimental measurement demonstrates that both of applied filters have near the same effect on measured values of radon volume activity in soil gas. The difference between radon volume activity values got by measuring without filter and with filters is low, in order of measurement error. Experiment did not evidence necessity of using filter for measuring radon volume activity in soil gas. Radon volume activity measurement error is in order of several kBq.m-3 . This fact brings uncertainty into obtained results. The absence of theoretically possible high content of solid radon daughter products in soil gas samples may be explained by possible adsorption of these particles on sampling and soil...
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