DETERMINATION OF URANIUM AND THORIUM IN ROCK SAMPLES FROM HARARGAJ ANTICLINE BY INSTRUMENTAL NEUTRON-ACTIVATION ANALYSIS

Uranium and thorium were determined in geological materials such as ra dioactive rock samples collected from the Harargaj Anticline in Moulav i Bazar. The pure instrumental neutron activation analysis (INAA) tech nique was used in qualitative and quantitative analysis of the rock sa mples for U and Th. The samples were properly prepared together with t heir standards and simultaneously irradiated in a neutron flux of the order of 10(12) n.cm-2.s-1 using the TRIGA MARK II reseach reactor fac ility at the AERE, Savar, Dhaka. After activation the samples were sub jected to gamma-ray spectrometry using a high purity germanium detecti on system. As a result of the analysis, U and Th could be determinated . Our data are consistent with the values reported by the ground radio metric survey group for some of the samples.