The possibility of using gamma-spectrometric measurements to solve problems of petroleum geophysics has been studied. A technique of separate determination of the uranium, thorium and potassium content is described, and rocks are characterized by their radioactivity. It has been shown that the spectrometric gamma-method provides more accurate lithological differentiation of rocks. The informativeness of the "uranium equivalent" for assessing the clay content is confirmed, and a high correlation of gamma radiation of clay minerals with their content is revealed. For terrigenous reservoirs, potassium-thorium radiation is preferable since it demonstrates better metrological characteristics.
Pak et al. (Thu,) studied this question.