Preliminary analysis of probabilistic seismic hazard assessment for nuclear power plant site in nigeria.

Abstract

Preliminary assessments of a suitable site for nuclear power plants and industrial constructions devoid of seismic shock and earthquake disaster in Nigeria have been carried out. We emphasized that the current tremor experienced across Nigeria is an indicator to an occurrence of large magnitude earthquake with possibilities of casualties and destructions of properties. This is in tandem with the seismicity of the west African region as experienced by some of the neighbouring countries: Ghana, (18th December, 1636 Ms= 5.7; 1862 ML∼ 6.5 and Ms ≥ 6.5; 11th February 1907 and 22nd of June 1939 Ms∼ 6.5 and mb∼ 6.4) and 22nd December 1983 (Mw∼ 6.3) in Guinea and volcanic eruption of mount Cameroun on August 21st, 1986 Fomine (2011) led to the death of 1,700 people. However, Ghana, Guinea, Cameroun and Nigeria are located in seismotectonic zone 1 of the African zonation map (IGCP [19]). Nigeria is considered as one of the gap areas where possible large magnitude earthquake is next to occurring. The study entails the use of Geographic Information System (GIS) and Probabilistic Seismic Hazard Analysis (PSHA). Peak ground acceleration (PGA) values were exclusively determined for two suitable zones of the GIS based site suitability studies, which were found to be useful for construction of nuclear power plants, where seismic and other related hazard are considered to the bearest minimum. Pertaining to site of study, during a large magnitude earthquake occurrence, the hazard is found to occur between the structural periods of 0.00 s and 0.5 s, therefore the engineering design of structure (building) must put in place a measure of resistance parameters to withstand the intensity of ground vibration up to 4 s. This will ensure the safety of structure or structures in case of large magnitude earthquake occurrence.