Study of equilibrium status among uranium and thorium series radionuclides in soil samples from Visakhapatnam, India

Surface soil samples from coastal region of Visakhapatnam were analyzed for uranium series and thorium series radionuclides by high-resolution gamma-ray spectrometry. Isotopic ratios of 226 Ra/ 238 U and 224 Ra/ 232 Th were calculated to investigate the radioactive equilibrium status in the samples. 226 Ra/ 238 U and 224 Ra/ 232 Th ratios were found to vary from 0.80–1.40 to 0.94–1.40 with mean values of 1.05 and 0.99, respectively. Results showed a prevalent radioactive equilibrium for both uranium and thorium series radionuclides in the surface soil of the study area.