Characterization of uranium in soil samples from a prospective uranium mining in Serule, Botswana for nuclear forensic application

摘要

This study attempts a nuclear forensic characterization of uranium in soil samples from a prospective Serule mine in Botswana. The analysis involves the determination of forensic signatures found in uranium-bearing materials from the mine. These signatures include 232Th activity concentration, isotopic and activity ratios of 232Th/238U and 235U/238U, impurity concentration, rare earth elements (REE), as well as the mineralogy of the area, all of which were determined using both Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) and X-ray Florescence (XRF) analytical techniques. Isotopic ratios determined reveal that there is a significant difference in the isotopic concentration, activity concentration of 232Th, 238U, and 235U, as well as the 232Th/238U isotope ratio between the uranium ores from each mine. The REE/chondrite analysis indicates clear patterns, suggesting that it is possible to use this feature as a unique identifier for Serule uranium ore source.