Estimation of Terrestrial gamma radiation (TGR) dose rate in characteristic geological formations of Jos Plateau, Nigeria


  • Habu Tela Abba Department of Physics, Faculty of Science, Universiti Teknologi Malaysia
  • Wan Muhammad Saridan Wan Hassan Department of Physics, Universiti Teknologi Malaysia, Skudai - 81310, Johor, Malaysia
  • Muneer Aziz Saleh Nuclear Engineering Programme, Faculty of Chemical and Energy Engineering, Universiti Teknologi Malaysia, Skudai - 81310, Johor, Malaysia.
  • Abubakar Sadiq Aliyu Department of Physics, Federal University Lafia, Nigeria
  • Ahmad Termizi Ramli Department of Physics, Universiti Teknologi Malaysia, Skudai - 81310, Johor, Malaysia



Geological formation, Gamma spectrometry, TGR dose rate, isodose map, Jos Plateau


A study was conducted to estimate the terrestrial gamma radiation (TGR) dose rates associated with the natural radionuclides 238U, 232Th and 40K in the characteristic geological formations of Jos Plateau. A total of 51 surface soils from all the geological units were collected and measured using high-resolution gamma ray spectrometry system. From the measured activity concentrations of 238U, 232Th and 40K, TGR dose rates in air outdoors 1 m above ground surface, were estimated to be in the range of 36 nGy h-1 to 456 nGy h-1, depending on the geological formation, with an overall mean value of 143 nGy h-1. The estimated mean value is by a factor of two higher than the world average value of 59 nGy h-1. Geological formation G8 (Younger granites) appear to have the highest mean TGR dose rate while G7 (sandstone, clay and shale) show the lowest mean TGR dose rate. The results of this study inferred that, TGR dose rates outdoors for Jos Plateau differs with the different geological formations and significantly contributed by 232Th. An isodose map for the distribution of TGR and exposure rate to the public due to natural sources was also plotted using ArcGIS software. The data here presented can be used to evaluate public radiation dose and to produce radiological map for the country.


Ademola, J. and Farai, I. (2006). Gamma activity and radiation dose in concrete building blocks used for construction of dwellings in Jos, Nigeria. Radiation protection dosimetry. 121(4), 395-398.

Akiba, S., Derin, M. T., Vijayagopal, P., Venkatraman, B., Chaubey, R. C. and Gopinathan, A. (2012). Radionuclides and Radiation Indices of High Background Radiation Area in Chavara-Neendakara Placer Deposits (Kerala, India). PLoS ONE. 7(11), e50468.

Al-Jundi, J. (2002). Population doses from terrestrial gamma exposure in areas near to old phosphate mine, Russaifa, Jordan. Radiation Measurements. 35(1), 23-28.

Chiozzi, P., Pasquale, V. and Verdoya, M. (2002). Naturally occurring radioactivity at the Alps–Apennines transition. Radiation Measurements. 35(2), 147-154.

Directive, C. (1996). Council Directive 96/29/Euratom of 13 May 1996 laying down basic safety standards for the protection of the health of workers and the general public against the dangers arising from ionizing radiation. Official J European Communities. 39(L159), 1-114.

Dragović, S., Janković, L., Onjia, A. and Bačić, G. (2006). Distribution of primordial radionuclides in surface soils from Serbia and Montenegro. Radiation measurements. 41(5), 611-616.

Florou, H. and Kritidis, P. (1992). Gamma radiation measurements and dose rate in the coastal areas of a volcanic island, Aegean Sea, Greece. Radiation Protection Dosimetry. 45(1-4), 277-279.

Garba, N. N., Ramli, A. T., Saleh, M. A., Sanusi, S. M. and Gabdo, H. T. (2015). Radiological mapping of Kelantan, Malaysia, using terrestrial radiation dose rate. Isotopes in environmental and health studies. 1-5.

Garmin Corporation (2008). GPS 12XL Personal Navigator, Operator’s manual & Reference.

Hassan, A., Raji, B., Malgwi, W. and Agbenin, J. (2015). The basaltic soils of Plateau State, Nigeria: Properties, classification and management practices. Journal of Soil Science and Environmental Management. 6(1), 1-8.

Isinkaye, M. (2013). Natural radioactivity levels and the radiological health implications of tailing enriched soil and sediment samples around two mining sites in Southwest Nigeria. Radiation Protection and Environment. 36(3), 122.

Jibiri, N. and Bankole, O. (2006). Soil radioactivity and radiation absorbed dose rates at roadsides in high-traffic density areas in Ibadan metropolis, southwestern Nigeria. Radiation protection dosimetry. 118(4), 453-458.

Macleod, W. N., Turner, D. C. and Wright, E. P. (1971). The Geology of Jos Plateau. Bulletin Geological Survey of Nigeria. 32 Vol1., pp. 12-47 pp.

Mollah, A., Rahman, M., Koddus, M., Husain, S. and Malek, M. (1987). Measurement of high natural background radiation levels by TLD at Cox's Bazar coastal areas in Bangladesh. Radiation protection dosimetry. 18(1), 39-41.

NGSA (1956). Geological formations of Jos Plateau, Naraguta (sheet 168): . Prepared British Government's Dept. of Technical Co-operation Under the Special commonwealth African Assistance Plan. Bases Map prepared from D.C.S 30 by Director of Federal Survey, Nigeria, 1956.

NPC (2006). National population Commission (NPC):. Provisional of 2006 Census Results.

Olise, F. S., Oladejo, O. F., Almeida, S. M., Owoade, O. K., Olaniyi, H. B. and Freitas, M. C. (2014). Instrumental neutron activation analyses of uranium and thorium in samples from tin mining and processing sites. Journal of Geochemical Exploration. 142, 36-42.

Olowolafe, A. E. (2008). Land use effects on the properties of an Alfisol on the Jos Plateau, Nigeria. GeoJournal. 71(2-3), 83-91.

Ramli, A. T. (1997). Environmental terrestrial gamma radiation dose and its relationship with soil type and underlying geological formations in Pontian District, Malaysia. Applied radiation and isotopes. 48(3), 407-412.

Ramli, A. T., Sahrone, S. and Wagiran, H. (2005). Terrestrial gamma radiation dose study to determine the baseline for environmental radiological health practices in Melaka state, Malaysia. Journal of Radiological Protection. 25(4), 435.

Ravisankar, R., Chandramohan, J., Chandrasekaran, A., Jebakumar, J. P. P., Vijayalakshmi, I., Vijayagopal, P. and Venkatraman, B. (2015). Assessments of radioactivity concentration of natural radionuclides and radiological hazard indices in sediment samples from the East coast of Tamilnadu, India with statistical approach. Marine pollution bulletin. 97(1), 419-430.

Saleh, M. A., Ramli, A. T., Alajerami, Y. and Aliyu, A. S. (2013). Assessment of environmental 226 Ra, 232 Th and 40 K concentrations in the region of elevated radiation background in Segamat District, Johor, Malaysia. Journal of environmental radioactivity. 124, 130-140.

Saleh, M. A., Ramli, A. T., Alajerami, Y., Aliyu, A. S. and Basri, N. A. B. (2013a). Radiological study of Mersing District, Johor, Malaysia. Radiation Physics and Chemistry. 85, 107-117.

Sanusi, M., Ramli, A., Gabdo, H., Garba, N., Heryanshah, A., Wagiran, H. and Said, M. (2014). Isodose mapping of terrestrial gamma radiation dose rate of Selangor state, Kuala Lumpur and Putrajaya, Malaysia. Journal of environmental radioactivity. 135, 67-74.

Tzortzis, M., Svoukis, E. and Tsertos, H. (2004). A comprehensive study of natural gamma radioactivity levels and associated dose rates from surface soils in Cyprus. Radiation protection dosimetry. 109(3), 217-224.

Tzortzis, M., Tsertos, H., Christofides, S. and Christodoulides, G. (2003). Gamma radiation measurements and dose rates in commercially-used natural tiling rocks (granites). Journal of Environmental Radioactivity. 70(3), 223-235.

UNSCEAR (1993). Sources and e=ects ofionizing radiation. Report to General Assembly, with Scienti,c Annexes, United Nations, New York.

UNSCEAR (1998). United Nation Scientific Commitee on the Effect of Atomic Radiation. Sources, Effects and Rsik of Ionizing Radiation, . New York 1998.

UNSCEAR (2000). Sources and effects of ionizing radiation: . UNSCEAR 1993 report to the General Assembly with scientific annexes / United Nations Scientific Committee on the Effects of Atomic Radiation.: New York: United Nations.

UNSCEAR (2008). Sources and effects of ionizing radiation. United Nations Scientific Committee on the Effects of Atomic Radiation, New York.

Zim, H. S. and Shaffer, P. R. (1957). Rocks and Minerals: A Guide to Minerals, Gems, and Rocks. Golden Press.