𝐔 𝟐𝟑𝟖 Radionuclides Series Ratios As A Guide For Alteration Processes Grades And Times of Different Rock Samples, Southwestern Sinai, Egypt

Abstract

The activity concentrations of the radionuclides 238U, 232Th and40K in twenty six sedimentary rock samples collected from four localities at southwestern Sinai, Egypt were measured using gamma-ray spectrometry with a high-purity germanium (HPGe) detector.The average activity concentration values of 238U are approximately 42, 34, and 50 times the world average value at EL-Qur, GabalHomeirat, andGabalHomyerlocalities, respectively. As for the fourth locality;GabalAllouga, the average activity concentration value of 238U is nearly two hundred and twenty times the world average value. 232Th average activity concentrationvalues for GabalHomeiratand GabalHomyer localities are less than the world average activityconcentration value while it is nearly twice the world average value for El-Qur and GabalAllougalocalities.The ratio 𝑅𝑎 226 𝑈 238 is classified into four grades indicating of alteration processes for the examined samples.The uranium migration was recorded for 12 samples.Eight samples from GabalAllougawere chosen to calculate their alteration processgrades and duration history which ranged between 106ka and 246ka