Browsing by Subject "uranium"

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Access status: Open Access ,
Alpha particle distribution and uranium mechanisms of accumulation in fossilised shells of ammonites and bivalves
(Wydawnictwa AGH, 2025) Długosz-Lisiecka, Magdalena; Tchorz-Trzeciakiewicz, Dagmara
The uranium concentration and distribution in fossils (ammonite and bivalve specimens) were studied. Fossil samples were cut perpendicularly and thin sections were prepared. The chemical and mineralogical compositions of fossils were analysed using scanning electronic microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS). The distribution of alpha emitters in the area of fossils was registered using CR-39 detectors. Alpha particle emitters were almost evenly distributed in all analysed fossils. We do not observe tracks concentrated in specific regions, which may indicate the absence of highly radioactive mineral grains. The uniformly distributed alpha tracks correlated with areas of mineral composition dominated by apatite, $Ca_{5}(PO_{4})_{3}(Cl/F/OH)$. The correlation between phosphorous content and alpha tracks suggests that this element was crucial in absorbing radionuclides, presumably uranium or other alpha particle emitters, uranium progenies. However, upon analysing the chemical composition on thin sections of fossils, uranium was not detected, likely due to its concentrations being below the detection limits of EDS. Areas on the thin sections devoid of alpha tracks on CR-39 detectors were associated with empty voids in thin sections, ooids partially composed of $FeS_{2}$ (pyrite framboids) or iron oxides $F_{2}O_{3}$ (hematite), phosphorus-free regions, or other areas where crushed fragments of shells composed of calcium carbonate (aragonite) partially filled internal casts. The interaction of elements presented in fossil structures with uranium can depend on various factors, such as the pH of the pore fluids, redox conditions, and the specific mineralogy of the sediments. Our research indicates that the increased radioactivity registered in some fossils is connected with phosphorous content. Small amounts of uranium are disseminated in calcium phosphate (various apatite forms). The uranium concentrations smaller than the detection limit of EDS can be successfully registered using passive track detectors.
Access status: Restricted ,
Charakterystyka mineralizacji kruszcowej w skałach formacji łupków z Gór Pieprzowych (Wyżyna Sandomierska)
(Data obrony: 2016-07-15) Stach, Paweł
Wydział Geologii, Geofizyki i Ochrony Środowiska
Góry Pieprzowe położone są w południowo-wschodniej części Polski w obrębie krainy geograficznej zwanej Wyżyną Sandomierską. Na podstawie odsłaniających się tam środkowo-kambryjskich utworów została wyróżniona formacja łupków z Gór Pieprzowych, do której zaliczane są skały tego samego wieku, występujące w Górach Świętokrzyskich. Niniejsza praca przedstawia mineralogiczno-petrograficzny opis utworów tej formacji ze szczególnym uwzględnieniem obecnej w nich mineralizacji kruszcowej. W wyniku przeprowadzonych badań stwierdzono, że okruszcowanie może być zarówno pochodzenia okruchowego, hydrotermalnego, wietrzeniowego, jak i biochemicznego. Wśród wyróżnionych minerałów rudnych wyszczególniono: goethyt, cyrkon, tytanit, leukoksen, rutyl, anataz, baryt, piryt oraz galenę. Obliczone zawartości uranu, toru oraz potasu w badanych skałach są charakterystyczne dla typowych łupków ilastych a ilość samego uranu, w porównaniu ze skandynawskimi łupkami ałunowymi, jest zdecydowanie niższa.
Access status: Open Access ,
Estimation of Natural Uranium and Its Risk-Assessment in Groundwater of Bangalore Urban District of Karnataka, India
(Wydawnictwa AGH, 2024) Naik, Poojashri Ravindra; Rajashekara, Vinod Alurdoddi; Mudbidre, Rajalakshmi
In this study, 56 groundwater samples were taken from diverse sources in Bangalore Urban district during the pre-monsoon and post-monsoon seasons to measure the uranium concentration and its correlation with different water-quality parameters. The uranium concentration varied from 0.94–98.79 µg/L during the pre-monsoon season and from 1.38–96.52 µg/L during the post-monsoon season. Except for a few readings, all were within the safe limit of 60 µg/L as prescribed by India’s Atomic Energy Regulatory Board (AERB), Department of Atomic Energy (DAE). Owing to its slightly higher concentration, a study on the radiological and chemical risks that are caused due to the ingestion of uranium was assessed. Based on the radiological aspect, cancer mortality and its risks were assessed, wherein all of the samples were well within the acceptable limit of $10^{-4}$, therefore, consuming these water samples was radiologically safe. However, when the risk that was caused by chemical toxicity was assessed, a few samples exceeded the hazard quotient (HQ) value of more than 1, thus illustrating that individuals were vulnerable to chemical risk. This paper features assessments of uranium and its risks to public health in groundwater samples if it exceeded the safe limit. Additionally, it recognizes the value of periodically assessing and treating the area’s drinking water sources.
Access status: Restricted ,
Identyfikacja minerałów ilastych na podstawie spektrometrycznego profilowania gamma w wybranych otworach
(Data obrony: 2012-07-18) Maciusiak, Marzena
Wydział Geologii, Geofizyki i Ochrony Środowiska
The aim of this thesis was to identify the various clay minerals in selected stratigraphic horizons in boreholes: Jabłonna 2 and Jabłonna 3, located in the Sudetic Monocline and Cierpisz 2 and Cierpisz 3, located in the Carpathian Foredeep. Overlays in the application ?Cross Plot? in the GeoWin system were used in order to realize the aim. Also, Author was focused on the presentation of the results of shaliness calculation according to the following formulas: linear, Larionov, Clavier, Stieberg and Larionov for the younger rocks to show variability of shaliness in the selected depth intervals. Also, the statistical analyzes were performed on the results of GG log and GRS log and Potassium log, and Thorium log and Uranium log to investigate the changes in the level of natural radioactivity of rocks in the geological profiles of boreholes.
Access status: Restricted ,
Mineralizacja kruszcowa występująca na hałdach po dawnym kopalnictwie żelaza i uranu w Kowarach i jej wpływ na środowisko naturalne
(Data obrony: 2010-09-30) Jerzykowska, Irena
Wydział Geologii, Geofizyki i Ochrony Środowiska
The aim of the study was to describe ore mineralization on iron and uranium mining dumps in Kowary and to estimate its influence on the local environment. Rock samples from four dumps, water flowing from adits and soil samples formed on dumps were collected. Fourteen ore minerals were described during macroscopic and microscopic studies. Mineral spatial relations indicate formation of ore minerals in a few stages of hydrothermal and metasomatic processes and finally during weathering. The radiochemical analysis of water flowing from adits shows that radionuclide content exceeds standard requirements for drinking-water. High heavy metal content (e.g. As, Ba, Sn, Pb, U) was noticed in soil samples collected from dumps. The highest uranium concentration was observed in the most acidic soil sample, rich in organic matter. Neutral pH contribute the crystallization of secondary uranium phases (e.g. uranophane).
Access status: Open Access ,
Ocena i wykorzystanie warunków środowiskowych w procesie wzbogacania kopaliny na drodze (bio)hydrometalurgicznej
(Wydawnictwa AGH, 2010) Konopka, Elżbieta; Kisielowska, Ewa
These are results of research on the possibility of enrichment uranium-bearing shales (black shales and walchia shales), which at a comparable, trace level of metal-bearing were strongly differed in their geochemical environments, which developed as a result of different compositions of microflora. Research was carried out on the dynamics of growth of micro-organisms most frequently represented in each of the geochemical environments and the associated with varying effectiveness of the leaching. It demonstrated that the enrichment of two radically different raw-shale materials using the biotechnical methods is possible, if taking into account every time changeable, individual and particular method, using the natural biogeochemical conditions of the raw material.
Access status: Open Access ,
Stosowanie nowych technik poszukiwania i eksploatacji złóż w odniesieniu do przepisów planistycznych i środowiskowych na przykładzie rud uranu i gazu łupkowego
(2011) Sadowska, Marzena; Syryczyński, Piotr
Current Polish rules and regulations of Geology and Mining Law connected with other acts of environment protection, land development, etc. are adjusted to current methods of documentation and mining of deposits. New methods of documentation and mining of deposits as well as ISL (in situ leaching) technologies in case of uranium deposits or chemical fracturing in case of shale gas deposits, requires serious changes in regulations and Geology and Mining Law as well as other acts related. Without regulations stated above Authors don't see the possibility in acquiring of international financing for realisation of such type of investment in Poland. Several changes to the Polish acta decrees was proposed.
Access status: Open Access ,
Study of uranium extraction process by the in-situ leaching method
(2009) Alibaeva, Karlygaš Abylhakovna; Tungatarova, Madina Sovetkalievna; Kul'džabekov, Alibek Bahidžanovič; Kaltaev, Ajdarhan; Bibosinov, Asylhan Žanibekovič
In present work modeling of mineral extraction by the In-Situ Leaching (ISL) method is considered. The low concentration deposit of uranium, gold, boron and other minerals is mined by the In-Situ Leaching method. The hydrodynamic pressure equation, Darcy law, equation of mineral dissolution, equations of liquid solution and dissolved mineral transfer in layer are described the processes leaking in exploitation block in mining mineral by ISL method. Because of nonlinearity of pressure equation, in general case iterative method over relaxation is used to solve it. The velocity field is defined from Darcy's law using hydrodynamic pressure distribution. The system of mineral dissolution equation, fluid solution and dissolved mineral transfer equations are solved together. The algorithm of these equations is following: equation of reagent transfer is obtained on each time step with ''classic''scheme. Using reagent distribution, mineral distribution on layer and concentration of dissolved useful component are defined from equation of mineral dissolution and transfer of dissolved mineral equation subsequently. The linear and hexagonal location of wells is considered. 3D fields of hydrodynamic pressure and velocity on layer under set of wells and the reagent distribution on layer, distribution of mineral in solid and fluid phase are obtained. The influence of wells location on rate and time of mineral extraction is investigated at the mining of mineral with ISL method.