Pattern of Seismicity Associated with the African Lithospheric Plate

Abstract

Knowledge of earthquake distribution pattern is very essential in exploration, understanding and forecasting of earthquake occurrence on the African plate. This paper focused on application of earthquake distribution pattern technique to investigate the regions of African plate that are prone to the seismic hazards. The earthquake epicenters for these regions were mapped out from the global seismicity map. The epicenters were located on Northern Africa (latitude 20°to 40°, longitude 0°to 50°), Southern Africa (latitude -10° to -30°, longitude 20° to 40°), Eastern Africa (latitude 10° to -25°, longitude 36° to 50°) and Western Africa (latitude 0° to 7°, longitude 0° to10°). The earthquake data corresponding with these epicenters were obtained from global earthquake catalogue. The data covered a 40-year period from January 1st 1974 to December 31st 2013 and in all, there were 58,649 earthquakes. The results obtained revealed that all the regions on the African plate are prone to a significant level of seismic hazard except the West African region. This signifies that the seismicity of Africa is mainly concentrated in two main regions - Northern and South-eastern Africa. This implied that the seismotectonic process is marked by a relative motion alternating between left and right lateral along the African and Eurasian plate.