Method and apparatus for logging a borehole employing dual radiation detectors
The disclosure relates to a method and apparatus for logging a borehole. A sonde having a source of penetrating radiation and at least two longitudinally-spaced radiation detectors is passed within a borehole. Count rate data is produced by each of the detectors and is continuously compared to predetermined count rate relationships which may be obtained from detectors operating in reference standard boreholes. In accordance with this count rate data comparison, the suitability of either the "ratio" or "spine/rib" analytical method is determined and the appropriate technique is automatically applied to produce an indication of a logged parameter such as formation porosity, selectively compensated for a borehole environmental condition such as variations in borehole diameter.
Halliburton Company
G G
G01V G01V
inventional inventional
Dan M.
Arnold