Pages: 166-176 Published: 7 Jun 2016
Views: 1,655 Downloads: 477
Abstract: Radiological investigations have been performed in Bansko-Razlog region, Bulgaria by means of high-resolution gamma-spectrometry of soil samples. The activity concentrations of the natural radionuclides 238U, 232Th and 40K as well as of the fission product 137Cs have been determined. The spatial distributions of the activity concentrations of the radionuclides are mapped and discussed. The comparison between spatial distributions of the activity concentrations of the 40K and 137Cs shows good negative correlation between activity concentrations of the two radionuclides. The highresolution map of spatial distribution of the ratio of the activity concentrations of 238U and 232Th shows a clearly visible increase in activity of 238U in east, adjacent to the former uranium mines. It has been shown that the continuous spatial distributions of the activity concentrations obtained by using the kriging interpolation allows us to obtain a more detailed picture of activity concentrations of the radionuclides compared with other statistical methods such as linear regression, etc.