Spatial investigation of some uranium minerals using nuclear microprobe

0490631 - ÚJF 2019 RIV US eng J - Journal Article
Valter, A. A. - Knight, K. B. - Eremenko, G. K. - Magilin, D. V. - Ponomarov, A. A. - Pisansky, A. I. - Romanenko, Oleksandr V. - Ponomarev, A. G.
Spatial investigation of some uranium minerals using nuclear microprobe.
Physics and Chemistry of Minerals. Roč. 45, č. 6 (2018), s. 533-547. ISSN 0342-1791. E-ISSN 1432-2021
Institutional support: RVO:61389005
Keywords : nuclear microprobe * electron microscope * mu-PIXE * SEM-EDS * uranium mineral * nuclear forensics
OECD category: Nuclear physics
Impact factor: 1.476, year: 2018

In this work, several individual grains of uranium minerals-uraninite with high content of Ca, Ca-rich boltwoodite, growths of uranophane with beta-uranophane, and weeksite-from different uranium deposits were studied by a scanning nuclear microprobe. Particle-induced X-ray emission technique provided by the microprobe (A mu-PIXE) was carried out to obtain a concentration and 2D distribution of elements in these minerals. In addition, energy dispersive X-ray spectrometry (SEM-EDS) provided by a scanning electron microscope was used. The types of minerals were determined by X-ray diffraction methods. Results of this study improved the understanding of trace elemental composition of the uranium minerals depending on their origin. Obtained signatures could be linked then to the sample provenance. Such data are important for nuclear forensics to identify the ore types and even specific ore bodies, when only small samples may be available for analysis. In this study, the A mu-PIXE technique was used for obtaining the 2D distribution of trace elements that are not commonly measured by SEM-EDS at the relevant concentrations. The detected levels and precisions of elements determination by A mu-PIXE were also defined. Using A mu-PIXE, several micro mineral inclusions such as phosphate with high level of V and Si were identified. The age of the uranium minerals was estimated due to a significant content of radiogenic Pb that provides an additional parameter for determination of the main attributive characteristics of the minerals. This work also showed that due to its high elemental sensitivity the nuclear microprobe can be a new analytical tool for creating a nuclear forensic database from the known uranium deposits and a subsequent analysis of the intercepted illicit materials.
Permanent Link: http://hdl.handle.net/11104/0284794