Earthquake catalogue of Ghana for the time period 1615–2003 with special reference to the tectono-structural evolution of south-east Ghana

Ghana is situated on the West Africa Craton and far away from any plate boundary. However, the southern part of the country is seismically active. The continental and coastal area of southeast Ghana is dominated by the Akwapim fault zone and coastal boundary fault. The Akwapim fault zone represents overthrusts of Neoproterozoic age, but there are also indications of recent faulting on some sections of the fault zone. The coastal boundary fault commenced to become tectonically active in Jurassic times and is probably still active. The two fault systems intersect some tens of kilometers to the southwest of Accra and it is at this intersection where most of the seismic activity has been observed.Historical documents describing damaging earthquakes in Ghana date as far back as 1615. The two major destructive earthquakes which struck Southern Ghana occurred close to the capital city Accra in 1862 (intensity IX) and 1939 (intensity VIII). The surveillance of the seismic activity of Southern Ghana with seismometers has been discontinuous with irregular long periods of disruption. All known earthquakes from 1615 to 2003, based on historical documents and instrumental recordings are collected in a data catalogue and compiled in a computer readable format. Based on macroseismic maps and detailed descriptions of the damages, the epicentral intensity of some strong events as well as the radii of different isoseismals could be newly estimated. The catalogue can be the basis for a deterministic seismic hazard assessment for Southern Ghana to develop a building code for this region.

► A catalogue of earthquakes from 1615 to 2003 have been compiled for Ghana.
► The earthquake dataset would serve as an input data for seismic hazard assessment.
► With the earthquake catalogue, the basis for a building code for Ghana is established.
► Deterministic seismic hazard maps with unique hazard parameters can now be generated.