8.1 Nuclear Well Logging
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characteristic intensity and energy of gamma rays that result from nuclear
interactions when fast neutrons bombard the formation. e intensity and
energy of the emitted γ rays is related to the elemental composition of the rock,
thus the volumetric occurrence of the elements in a bulk rock mass intersected
by a borehole, can be directly estimated.
Downhole nuclear logging has certain benefits over conventional core
and drill-chip assaying. A much larger volume of the material surround-
ing the borehole is sampled than the sample taken for laboratory analysis,
thus providing better sampling statistics. Provided a suitable calibration
exists, data processing can be automated for quick turnaround of results
(near r