Routine Quantitative Spectral Analysis of Natural Gamma Radiation on Cores Including Measurement of Core Density, Diameter and Pe-Value


R.T. Wittebrood,
Shell Canada Limited


Spectral analysis of natural gamma radiation on cores from oil wells is now routinely available in the core services industry. However, the results are not always quantitative, because for cores corrections are more difficult to apply than in the well bore. For cores, the raw count-rates are affected not only by variable background radiation, but also by variations in the core diameter and the core density. Furthermore, the amount of radioactivity from a core is usually so small that advanced data processing is required to attain the same accuracy as is available on wireline logs.