Volume 30 Number 6
  • E-ISSN: 1365-2478



Nonlinear correction parameters have been determined to correct broadband gamma ray logs for the effects of photoelectric absorption in zones of high‐grade uranium mineralization. These corrections have been determined empirically by logging artificial test pits. The corrections are a function of grade of mineralization, hole casing thickness, hole medium, and probe energy thresholds. Comparisons between core assays from a high‐grade mineralized zone and corrected log inversions recorded with both low‐threshold and high‐threshold filtered probes are made. The best correlations were obtained between assays and inversion solutions for the low‐threshold probe. This reflects the superior counting statistics of this type of probe. Filtered probes reduce ‐effect errors but do not eliminate them, and have poorer counting statistics than unfiltered probes.


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  • Article Type: Research Article
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