Radon emanation and soil moisture effects on airborne gamma-ray measurements

摘要

A theoretical model is developed to explain variations in airborne gamma-ray measurements over a calibra- tion range near Ottawa, Ontario. The gamma-ray flux from potassium and the thorium decay series showed an expected decrease with increasing soil moisture. How- ever, the gamma-ray flux from the uranium decay series was highest in the spring when the ground was water- saturated and even covered with snow.