Chemical and Sr isotopic characterization of North America uranium ores: Nuclear forensic applications. (November 2016)

• Record Type: Journal Article
• Authors: Balboni, Enrica; Jones, Nina; Spano, Tyler; Simonetti, Antonio; Burns, Peter C.
• Is Part Of: Applied geochemistry. Volume 74(2016:Nov.)
• Page Start: 24
• Page End: 32
• Publication Date: 2016-11
• Subjects: Uranium deposits in the United States -- Uranium ore concentrate -- Strontium isotopes -- ICP-MS; Environmental geochemistry -- Periodicals; Water chemistry -- Periodicals; Geochemistry -- Social aspects -- Periodicals; Geochemistry -- Periodicals; 551.9
• DOI: 10.1016/j.apgeochem.2016.08.016
• Languages: English
• ISSNs: 0883-2927

Abstract

Abstract: This study reports major, minor, and trace element data and Sr isotope ratios for 11 uranium ore (uraninite, UO2+x ) samples and one processed uranium ore concentrate (UOC) from various U.S. deposits. The uraninite investigated represent ores formed via different modes of mineralization (e.g., high- and low-temperature) and within various geological contexts, which include magmatic pegmatites, metamorphic rocks, sandstone-hosted, and roll front deposits. In situ trace element data obtained by laser ablation-ICP-MS and bulk sample Sr isotopic ratios for uraninite samples investigated here indicate distinct signatures that are highly dependent on the mode of mineralization and host rock geology. Relative to their high-temperature counterparts, low-temperature uranium ores record high U/Th ratios (>1000), low total rare earth element (REE) abundances (<1 wt%), high contents (>300 ppm) of first row transition metals (Sc, Ti, V, Cr, Mn, Co, Ni), and radiogenic 87 Sr/ 86 Sr ratios (>0.7200). Comparison of chondrite normalized REE patterns between uraninite and corresponding processed UOC from the same locality indicates identical patterns at different absolute concentrations. This result ultimately confirms the importance of establishing geochemical signatures of raw, uranium ore materials for attribution purposes in the forensic analysis of intercepted nuclear materials. Highlights: Trace elements, REE and 87 Sr/ 86 Sr signatures of uranium ores can be used as fingerprints for provenance studies. Low temperature uranium ore record low REE abundances (<1 wt.%) and high contents (>300 ppm) of first row transition metals. Low temperature uranium ore record low 87 Sr/ 86 Sr ratios (<0.7200). Direct comparison of REE between uranium ore and uranium ore concentrate (UOC) from Wyoming indicates identical patterns