Author(s)

Bashayer M. Al-Zahrani^1*, Haifa S. Alqannas², Safia H. Hamidalddin²

¹Physics Department, Faculty of Science, Al Baha University, Al Baha, Saudi Arabia.
²Physics Department, Faculty of Science, University of Jeddah, Jeddah, Saudi Arabia.

In this work, gamma-ray spectroscopy based on semiconductor hyper pure germanium (HPGe) detector was used to evaluate the activity concentrations of the natural radionuclides (U-238 (Ra-226), Th-232 and K-40) and the fallout nuclide (Cs-137) for thirty samples of igneous and sedimentary rocks of Al-Atawilah (Al-Baha). The mean values of the activity concentrations of U-238 (Ra-226), Th-232, K-40 and Cs-137 in the igneous samples are found as (11.0, 11.50, 1172.71, 1.47) Bq/Kg respectively. In the sedimentary rocks, the mean values of the activity concentrations of the natural radionuclides (U-238 (Ra-226), Th-232 and K-40) and the fallout nuclide (Cs-137) equal to (12.04, 13.18, 1131.36, 1.60) Bq/Kg respectively. The averages of radiological hazards (Ra_eq, H_ex and I_γ) were calculated and found to be within the UNSCEAR permissible limit values (370 Bq/kg for Ra_eq, and 1 for H_ex and I_γ), except for a slight increase of average value of I_γ in the igneous rock samples (1.36). The results indicate that the dose rate values depend on the kind of rocks (high in some igneous rock samples, and most of sedimentary rock samples have low dose rate). The activities of naturalnuclides were predicted and simulated in T time using a written MATLAB R2020a script based on the average activity concentrations and respective half-lives of U-238 and Th-232 series, and K-40, this is to evaluate the future effects of natural radionuclides on the population and estimate the human inputs in the future.

Natural Radioactivity, Gamma-Ray Spectroscopy, Activity Concentration, Igneous and Sedimentary Rocks, Simulated in T Time

Al-Zahrani, B. , Alqannas, H. and Hamidalddin, S. (2020) Study and Simulated the Natural Radioactivity (NORM) U-238, Th-232 and K-40 of Igneous and Sedimentary Rocks of Al-Atawilah (Al-Baha) in Saudi Arabia. World Journal of Nuclear Science and Technology, 10, 171-181. doi: 10.4236/wjnst.2020.104015.