9th International Physics Conference of the Balkan-Physical-Union (BPU), İstanbul, Türkiye, 24 - 27 Ağustos 2015, cilt.1722
In order to determine the radioactivity level at Izmit Bay Marmara Sea, marine sediment samples were collected from five different locations. The radioactivity concentrations of naturally occurring U-238,Th-232 and K-40 isotopes and also that of an artificial isotope Cs-137 were measured by using gamma-ray spectroscopy. Preliminary results show that the radioactivity concentrations of (238)w and Th-232 isotopes are lower than the average worldwide values while the radioactivity concentrations of the 40K are higher than the average worldwide value. A small amount of Cs-137 contamination, which might be caused by the Chernobyl accident, was also detected.