1887
Volume 44, Issue 3
  • ISSN: 0812-3985
  • E-ISSN: 1834-7533

Abstract

Calibration facilities for total-count radiation probes used to measure high-grade uranium (> 2 %) are scarce and the conventional method using correction factors to convert to equivalent uranium has severe shortcomings. In this paper gamma-ray transport modelling is utilised to directly convert logging data into U grade estimates, taking into account casing, water, borehole diameter, probe size and detector shielding corrections which at high U grades are dependent on the U grade itself. The method uses interpolation between modelled results and avoids the usual calibration factors. It is demonstrated using data collected at the Angela U deposit, Northern Territory, and at the Kintyre deposit, Western Australia. At the Kintyre deposit, the uranium grades exceed 20% and both unshielded and shielded NaI(Tl) detectors were tested, with the latter showing the best performance at high grades.

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2013-09-01
2026-01-18
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  • Article Type: Research Article
Keyword(s): dead-time; gamma ray; GEANT; high grade; Kintyre; logging; modelling; uranium

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