West Africa is considered a region of low seismicity. However, the
monitoring of earthquake activity by local seismic arrays began very early (as
early as 1914) in West Africa but seismic catalogs are very incomplete. In
1991, Bertil studied the seismicity of West Africa based on networks of seismic
stations in Ivory Coast and neighboring countries. The reference work of
Ambraseys and Adams as well as the recent earthquakes given by the
international data centres on the seismicity of West Africa were also used for
the computations of earthquake hazard parameters. Different earthquake event
data have been compiled and homogenised to moment magnitude (Mw). The obtained catalog
covers a period of over four centuries (1615-2021) and contains large
historical events and recent complete observations. The complete catalog part
has been subdivided into four complete subcatalogs with each a level of
completeness. The minimum magnitude and the maximum observed magnitude are
equal to 2.89 and 6.8 respectively for the whole catalog. The seismic code
software developed by Kijko was used to calculate the earthquake hazard
parameters. The results give a bvalue
of 0.83 ± 0.08 for the whole period and preliminary seismic hazards curves are
also plotted for return periods 25, 50 and
100 years. This is a good and practical example showing that this
procedure can be used for seismic hazard assessment in West Africa.
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