Radiogenic Heat Production Due to Natural Radionuclides in Soil and Sediments of Coastal Communities of Okrika Local Government Area of Rivers State, Nigeria

Abstract

Thirty-six samples of soil and sediments were analyzed for radiogenic heat production due to three natural radionuclides from the Coastal communities of Okrika Local Government Area of Rivers state, Nigeria. 18 samples of soil samples were dug at a depth of 1 meter below the earth surface, and 18 samples of sediments were obtained from the bottom of the riverbed at a depth of 10-20 cm depth. Both samples are air-dried pulverized to fine fines and sealed in an air-tight container, left so several days to ensure secular equilibrium. The analysis was successfully carried out using NaI(Ti) Gamma-Ray Spectrometer to determine the radionuclides elementary composition of soil and sediment samples in terms of 40K, 238U and 232 Th respectively. The radiogenic heat production rate of soil ranged from 0.0058 µW/m3 to 0.0245 µW/m3 with a mean of 0.01255±0.02 µW/m3, while for sediment it varied from 0.0030 µW/m3 to 0.0131 µW/m3 a mean value of 0.01255±0.02 µW/m3. The result indicates that the coastal communities of Okrika had shown low radiogenic heat production rate. The soil and sediment samples from the coastal areas of Okrika shows low radiogenic heat production rate. The radiogenic heat production rate of soil and sediments was mostly from 238U in the order of 238U > 232Th > ⁴⁰K. Therefore, the radiogenic heat production rate determined for the coastal communities of Okrika as presented in this study, serves as baseline data and the basis for further investigations/research of its impact in the study area, and also creates a facet for hydrocarbon and geothermal energy resource investigation of the region.