Radiogenic Heat Model in the southern axis of Ogbomoso, SW Nigeria

Abstract

This study is aimed at estimating the radiogenic heat model in the southern part of Ogbomoso, Nigeria. In-situ measurements of activity concentrations of radioelements are randomly taken at seven locations. The individual data point is measured four times, while the average was recorded for accuracy. The results showed that the radiogenic heat produced per radionuclide varies from 28.71 to 143.55 ρW kg-1 for 238U; 89.60 to 217.60 ρW kg-1 for 232Th; 0.0010 to 0.0063 ρW kg-1 for 40K; with mean values of 73.83, 151.04 and 0.0033 ρW kg-1 for 238U, 232Th and 40K respectively. The total radiogenic heat production in the study area varies from 136.23 to 303.73 ρW kg-1, with mean value of 224.87 ρW kg-1. It is shown that thorium is the major contributor to the total heat generated in the study area. The study area is characterized by low heat production potential, which could be attributed to depletion of thorium and uranium in the geological rocks in the environs. Comprehensive radiometric survey to cover the entire city is recommended. This will help in characterization of the radiogenic heat produced per geological unit.