Ground gamma-ray survey of the Solforata gas discharge area, Alban Hills-Italy:A comparison between field and laboratory measurements

摘要

Measurements of environmental radioactivity by HPGe gamma-spectrometry were carried out with the aim of investigating the distribution of natural radionuclides in a volcanic area and to compare two different methodologies - an in situ gamma-survey of the area and high accuracy laboratory measurements of soil samples. Results demonstrate good performance of the in situ technique, also confirmed by a correlation analysis between the results obtained by the two methodologies. A volcanic gas discharge area was chosen as the test site for the presence of natural long-lived radionuclides such as ~(40)K and ~(238)U, ~(235)U and ~(232)Th, and their decay chain members. Clear evidence of ~(222)Rn degassing in the area was confirmed by ~(226)Ra values measured by the in situ technique. Higher ~(40)K values measured by the in situ technique may be attributed to the presence of vegetation in the study area.