Natural radioactivity-rock clayiness relation

The nature of hte dependence of radioactive elements (Th, K, Ra) and total radioactivity on the clayiness of rocks was studied using gamma-logging data for sand-aleurolite deposits in some oil-bearing basins of Turkmenia. It is shown that the nature of the general relationship between the total radioactivity and clayiness of rocks changes depending on the contribution of radioactive elements to the total gamma radiation of rocks. The most obvious correlation exists between the content of K and Th and the clayiness. There is no correlation between Ra and the clayiness. When it is K which makes the greatest contribution to the total radioactivity of rocks then the function of the radioactivity versus clayiness is of the curved type; and it is approximately linear when the greatest contribution is made by Th; when Ra makes the greatest contribution, then the function of the total radioactivity versus clayiness is distorted. The necessity of well gamma-spectrometric measurements is shown to derive quantitative estimates of clayiness of rocks for each gas- and oil-bearing basin and stratigraphic deposit complex