Assessment of radiogenic heat production due to 238U, 232Th and 40K in surface soils of Ortum region, west Pokot county, Kenya

The activity concentrations of ²³⁸U, ²³²Th and ₄₀K in Bq/kg were determined using a HPGe detector at the Institute of Nuclear Science and Technology at the University of Nairobi (Kenya). The activity concentrations were then converted into ppm (²³⁸U and ²³²Th) and % for ⁴⁰K that were used for computing Radiogenic Heat Production (RHP) for individual radionuclides and the overall RHP contributed by the three radionuclides. The average activity concentrations were 3.198753ppm, 13.42265ppm and 1.372154% for ²³⁸U, ²³²Th and ⁴⁰K respectively. The average RHP for the individual radionuclides was found to be 0.239883µW/m³, 0.2658µW/m³ and 0.036378µW/m³ for ²³⁸U, ²³²Th and ⁴⁰K respectively. the overall RHP contribution by the three radionuclides was found as 0.540764 µW/m³. All the RHP values for the individual radionuclides including their overall contribution was below the world RHP value of 1µW/m³. The findings of this study will provide benchmark information on RHP status of the study area that can be extended to other areas to enable possible geothermal energy exploitation.