Intrinsic germanium detector used in borehole sonde for uranium exploration

F. E. Senftle; R.M. Moxham; A. B. Tanner; G. R. Boynton; P. W. Philbin; J.A. Baicker

doi:10.1016/0029-554x(76)90047-1

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Intrinsic germanium detector used in borehole sonde for uranium exploration

F. E. Senftle·R.M. Moxham·A. B. Tanner·G. R. Boynton·P. W. Philbin·J.A. Baicker

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Abstract

A borehole sonde (~1.7 m long; 7.3 cm diameter) using a 200 mm 2 planar intrinsic germanium detector, mounted in a cryostat cooled by removable canisters of frozen propane, has been constructed and tested. The sonde is especially useful in measuring X- and low-energy gamma-ray spectra (40–400 keV). Laboratory tests in an artificial borehole facility indicate its potential for in-situ uranium analyses in boreholes irrespective of the state of equilibrium in the uranium series. Both natural gamma-ray and neutron-activation gamma-ray spectra have been measured with the sonde. Although the neutron-activation technique yields greater sensitivity, improvements being made in the resolution and efficiency of intrinsic germanium detectors suggest that it will soon be possible to use a similar sonde in the passive mode for measurement of uranium in a borehole down to about 0.1% with acceptable accuracy. Using a similar detector and neutron activation, the sonde can be used to measure uranium down to 0.01%.

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F. E. Senftle, R.M. Moxham, A. B. Tanner, G. R. Boynton, P. W. Philbin, J.A. Baicker. 1976. Intrinsic germanium detector used in borehole sonde for uranium exploration. https://doi.org/10.1016/0029-554x(76)90047-1

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