Multi-scale visualization of uranium-rich domains dispersed in U-Zr mineralization of sandstone-type (Brevniste, Czech Republic)

článek v časopise ve Web of Science, Jimp

angličtina

Multi-level visualization of U-Zr mineralization in sandstones is discussed, aiming at the identification of mineral phases, imaging of their distribution using 2D and 3D projections, and quantification of the presence of U-rich domains. For this purpose, uranium-bearing sediments with anomalous concentrations of Zr, Nb +/- Fe, Sr were studied (Brevniste deposit, Czech Republic). The applied multi-instrumental approach included selection of the most suitable areas in core samples (highest U and Zr concentrations) using X-ray fluorescence analysis (XRF). The presence of numerous detrital and authigenic accessories, hardly discernible using optical methods, was confirmed with the use of automated mineralogical analysis (TIMA). Hydrozircon and metacolloidal mixed phases were shown to be the carriers of uranium. Their close relationship to sulfides, Fe oxyhydroxides and clay minerals was documented using phase distribution maps. X-ray micro-computed tomography (mu CT) was used for the visualization of internal structures of uranium-bearing sandstones. Based on a series of thresholding of mu CT data, segmentation of selected samples was performed with subsequent visualization of selected mineral phases. The combination of TIMA and mu CT analysis allowed for an effective discrimination of U-rich areas and quantification of their volume. This approach provides new possibilities in imaging elementary complex disseminated uranium mineralizations.

Computed tomography; Automated mineralogy; Uranium deposit; Sandstones; Zirconium

MIKYSEK, P.; ZIKMUND, T.; DOSBABA, M.; BŘÍNEK, A.; SLOBODNÍK, M.; ADAMOVIČ, J.; MÉSZÁROSOVÁ, N.; TROJEK, T.; KAISER, J.

1. 11. 2021

ELSEVIER

AMSTERDAM

1872-7360

ORE GEOLOGY REVIEWS

138

1

Nizozemsko

104358-1

104358-16

16

https://www.sciencedirect.com/science/article/pii/S016913682100384X?via%3Dihub