EFFECT OF PHYSICOCHEMICAL PROPERTIES ON RADIONUCLIDES DISTRIBUTION IN SEDIMENTARY ROCK SAMPLES, SINAI, EGYPT

Abstract

The main target of this study is to find the effect of physical and chemical properties on the distribution of different radionuclide in different phases of different sedimentary rocks in Um Bogma Formation from Farsh El Azraq area in Sinai. In First stage, the activity concentrations (Bq/kg) of the naturally occurring radionuclide's 238 235 U, 234 U, 226 U, 232 Ra, Th, and 40 K were measured by using high purity germanium detector (HpGe) and the activity ratios 226 238 Ra/ 234 U, 238 U/ 238 U, 235 U/ 234 U, 235 U/ U were calculated to estimate the radioactive equilibrium/disequilibrium in the area under study, also the radiation hazard indices (external hazard index, radium equivalent, absorbed dose, outdoor annual effective dose rates, excess lifetime cancer risk and annual gonadal dose equivalent) were calculated. The radon emanation factor, the radon mass exhalation rate and radon annual effective dose have been calculated in these locations. The results shown that, the concentrations of determined radionuclides are changed for each type of sedimentary rocks. The activity concentration by Bq/ kg for 238 226 U, 232 Ra, Th and 40 K varied between [717.09 ± 21.51 and 6819.65 ± 204.59] (Bq/kg), [842.86 ± 25.28 and 9666.95 ± 290.01] (Bq/kg), [29.85 ± 0.89 and 170.46 ± 5.11] (Bq/kg) and [345.38 ± 10.36 and 856.54 ± 25.70] (Bq/kg), respectively were higher than the world's average. All radiation hazard indices have high values. All the studied samples measurements indicate high levels of annual effective dose