Radionuclide distribution in Mediterranean and Marmara Sea sediments: influence of geochemistry and sediment texture
摘要
This study investigated the activity concentrations of natural radionuclides (226Ra, 232Th, 40K, 210Pb) and the anthropogenic radionuclide (137Cs) in marine sediments from the Mediterranean and Marmara Seas, Türkiye. The study further evaluated their relationships with sediment texture and geochemical composition. Activity concentrations were determined by high-purity germanium (HPGe) gamma spectrometry, while grain-size distribution and chemical composition were analyzed using standardized geotechnical tests and X-ray fluorescence spectroscopy. Mean activity concentrations for all samples were 6.8 Bq kg−1 (226Ra), 13.6 Bq kg−1 (232Th), 210.5 Bq kg−1 (40K), 56 Bq kg−1 (210Pb), and 3.9 Bq kg−1 (137Cs). Correlation and principal component analyses suggest positive relationships between radionuclide activities and clay content and negative relationships with sand content. The results suggest that bulk geochemical composition, sediment texture and basin setting may contribute to radionuclide variability in Turkish coastal sediments.