Geographical mapping and associated fractal analysis of the long-lived Chernobyl fallout radionuclides in Greece

Immediately after the Chernobyl accident, a soil sampling programme was undertaken in order to detect and quantitatively analyse the long-lived radionuclides in the Chernobyl fallout. Soil samples (1242 in number) of 1 cm thick surface soil were collected in Greece during the period from MayNovember 1986. The samples were counted and analysed using Ge detector set-ups. The ¹³⁷Cs fallout data have already been analysed, mapped and published. In an attempt to improve this analysis and also to extend it to other fallout radionuclides, an in-house unix-based data base/geographical information system (DBGIS) was developed. Multifractal analyses of the deposition patterns have also been performed. In the present work, an analysis of the results of the deposition of ¹³⁷Cs, ¹³⁴Cs, ¹⁴⁴Ce, ¹⁴¹Ce, ¹²⁵Sb, ^110mAg, ¹⁰⁶Ru, ¹⁰³Ru, ⁹⁵Zr and ⁵⁴Mn are presented together with relevant fractal analysis and three characteristic contour maps. The maximum detected values of the above-mentioned radionuclides were 149.5±0.1, 76.1±0.1, 32.9±0.2, 46±2, 4.56±0.02, 7.98±0.02, 79.1±0.4, 337±2, 20.1±0.2 and 3.02±0.02 kBq m², respectively. Furthermore, a statistical technique to compare contour maps was introduced and applied to explain the differences which appeared in the maps of the above-mentioned radionuclides.