Distribution of natural radionuclides in the soils and assessment of radiation hazards in the Khrami Late Variscan crystal massif (Georgia)

This study was performed to determine the distributions of radionuclides ((238)U, (232)Th and (40)K naturally occurring in Khrami Late Variscan crystal massif and soils overlapping its adjacent territory built by Neogene and Quaternary lava using a gamma-ray spectrometry with an HPGe detector. By identification of artificial radionuclide (137)Cs concentration revealed the character of radioactive contamination of the area under investigation. Based on the obtained results, the radiological parameters (outdoor absorbed gamma dose rate, annual effective dose; radium equivalent activity) were estimated to assess radiation hazards caused by use of industrial materials. The difference was established between concentrations of radionuclides having emerged at the expense of Late Variscan crystal substrate and recently erupted lavas. The results were compared with similar studies conducted in different countries and with data and recommendations published by international organizations (UNSCEAR, ICRP).