RADIATION PROTECTION DOSIMETRY, cilt.141, sa.2, ss.192-198, 2010 (SCI-Expanded)
The surveys of natural gamma-emitting radionuclides in rocks and soils from the Ezine plutonic area were conducted during 2007. Direct dose measurement using a survey meter was carried out simultaneously. The present study, which is part of the survey, analysed the activity concentrations of U-238, Th-232 and AUK in granitoid samples from all over the region by HPGe gamma spectrometry. The activity concentrations of Ra-226 ranged from 94 to 637 Bq kg(-1), those of Th-232 ranged from 120 to 601 Bq kg-land those of K-40 ranged from 1074 to 1527 Bq kg(-1) in the analysed rock samples from different parts of the pluton. To evaluate the radiological hazard of the natural radioactivity in the samples, the absorbed dose rate (D), the annual effective dose rate, the radium equivalent activity (Ra-eq) and the external (H-ex) hazard index were calculated according to the UNSCEAR 2000 report. The thorium-to-uranium concentration ratios were also estimated.