The seismotectonics of Western Africa show the occurrence of major earthquakes (e.g., 1636 southwestern Ghana, 1855 offshore Monrovia, 1939 offshore Accra, and 1983 Gaoual-Guinea) and prominent offshore transform faults. However, there is no analysis that links the continental active tectonics with the oceanic fault zones of the Gulf of Guinea. We study the active tectonics by firstly mapping the main transform faults using a combination of bathymetric, gravimetric, and magnetic data. The data analysis associates regional seismicity (historical and instrumental) with focal mechanisms as extracted from the recently published seismotectonic map of Africa. We identify active transform faults, the Chain (CFZ), Romanche (RFZ), Saint Paul (SPFZ), and Arkhangelskiy (AFZ) fault zones. We also calculate strain rates on these faults from Late Cretaceous (–85 Ma) to present time using paleomagnetic data and infer slip rates from the seismic moment data. The strain rates show a first stable trend around 2 cm/year and then accelerate to 4 cm/year in the last 10 million years. The comparison of Late Quaternary strain rates with geodetic strain rates shows an accumulation of seismic energy that could lead to the initiation of an Mw 7–7.5 earthquakes on the Saint Paul transform fault. Our seismotectonic analysis clearly links oceanic and continental tectonics, with about a 20°–30° anticlockwise fault trend rotation for CFZ, RFZ, and SPFZ. The potential for the occurrence of large earthquakes in the Gulf of Guinea should be taken into account for a realistic regional seismic and tsunami hazard of the Gulf of Guinea.

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