Terrestrial gamma exposure in the granodiorite area of Bergama (Pergamon)–Kozak, Turkey

As higher radiation levels are associated with granite and Bergama (Pergamon) has increasingly become a large market for granite use over the last years, an extensive investigation was started in 2009. Samples from the granites and soils underlying this area were collected and analyzed by HPGe gamma spectrometry system. The specific activities of the naturally occurring radionuclides 226Ra, 232Th, and 40K were found to be in the range of 29–111 Bq kg−1 for 226Ra, 35–87 Bq kg−1 for 232Th and 698–1100 Bq kg−1 for 40K in granite samples. The ranges of 226Ra, 232Th, and 40K activity concentrations for soils were 32–82, 42–88 and 667–1127 Bq kg−1, respectively. From these data radiological parameters were calculated and compared with respective data from the UNSCEAR reports.