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A comparison of radiative capture with decay gamma-ray method in bore hole logging for economic minerals

F. E. Senftle·R.M. Moxham·A. B. Tanner
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Abstract

The recent availability of borehole logging sondes employing a source of neutrons and a Ge(Li) detector opens up the possibility of analyzing either decay or capture gamma rays. The most efficient method for a given element can be predicted by calculating the decay-to-capture count ratio for the most prominent peaks in the respective spectra. From a practical point of view such a calculation must be slanted toward short irradiation and count times at each station in a borehole. A simplified method of computation is shown, and the decay-to-capture count ratio has been calculated and tabulated for the optimum value in the decay mode irrespective of the irradiation time, and also for a ten minute irradiation time. Based on analysis of a single peak in each spectrum, the results indicate the preferred technique and the best decay or capture peak to observe for those elements of economic interest.

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F. E. Senftle, R.M. Moxham, A. B. Tanner. 1972. A comparison of radiative capture with decay gamma-ray method in bore hole logging for economic minerals. https://doi.org/10.1016/0029-554x(72)90601-5

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