Airborne #betta#-ray spectrometry in uranium exploration. Principles and current practice

Experiments have shown that the radioelement content of bedrock is generally reflected by that of overlying till and that areas showing broad regional enrichment of radioelement concentrations are favourable for uranium exploration. Airborne #betta#-ray spectrometry with equipment having typical sodium iodide detector volumes of 50 L is used to record the natural radiation intensity due to potassium, uranium and thorium by flying grids at ground clearances of about 120 m. #betta#-ray spectra are recorded continuously in flight with navigational data all of which is processed off-line to produce maps of radioelement distribution with concentration contours. (author)