Study on radon emission in a fault located in the Bergamask Pre-Alps

ABSTRACT

At Bedulita in the Orobic Prealps the Institute of Applied Physics has placed a radon continuos monitoring station. The experimental apparatus is located in a dry well, 4 metres deep, on an active fault. Radon is measured by means of a NaI detector that reveals the y quanta of Radon decay products. The hourly are recorded on magnetic diskette every hour. The station has worked since 1989 until 1992. The seasonal variation with winter minima and summer maxima present in all the four years of measurements appears very interesting. We have also noticed a diurnal modulation and some sudden peaks during the months of lower emission. Twice a week, during June and July 1992 helium has been measured. The air samples collected in the dry well has been analysed in the laboratoey of the Institute by a mass spectrometer. The correlation between He and Rn is evident.(AU)