Nuclear Reactions Logging
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e COR model is based on the fact that the ratio of C and O yields is a mea-
sure of the amount of oil around the tool. is ratio depends on many variables
including oil saturation, borehole oil fraction, porosity, lithology, borehole
diameter, casing diameter, and casing weight.
Although the ratio of carbon and oxygen yields is a measure of the amount
of oil around the tool, it should be realized that a carbon signal can originate
from several sources including the borehole, the cement behind the casing, the
formation rock, and the formation uid. In order to evaluate these contribu-
tions individually, we are proposing the modication of the neutron genera-
tor by the insertion of segmented associated alpha particle ...