The seismicity of southern Africa is discussed in terms of seismicity maps, the completeness of the existing catalogue of seismic events for the region and frequency-magnitude relationships. The present catalogue of earthquakes seems to be complete for events of ML ≥ 4.6 since 1950, for events of ML ≥ 4.9 since 1910 and for events of ML ≥ 5.3 since 1906. Analysis of earthquake statistics reveals a b-value for natural earthquakes of 1.1, increasing to 1.5 for mine tremors. It is suggested that the maximum expected magnitude of an earthquake in the region is in the order of M = 7.5 and that mine tremors as high as M ~ 5 1 2 may occur. It is concluded that much more high quality data from more seismograph stations are required to sensibly investigate the seismotectonic characteristics of the region.
ASJC Scopus subject areas
- Earth-Surface Processes