The Ghana, Accra Earthquake of June 22, 1939

This earthquake, which caused the deaths of seventeen people and injury to upwards of 135 others, besides doing damage to buildings to the extent of hundreds of thousands of pounds in Accra, the capital of the Gold Coast and the surrounding country (NATURE, 144, 18; 1939), has recently been the subject of comprehensive research. The Gold Coast as a whole is a relatively stable region and earthquakes are rare, though the Accra district and the coastal area to the east and west are subject to earthquakes. Major shocks occurred in 1862, when every stone building in Accra was razed to the ground and Christiansborg Castle and the forts at Accra taken over by the British from the Danes twelve years before, were rendered uninhabitable; in 1906 when on November 20 Government buildings in Accra were damaged though no casualties were reported; and in the present instance. Recorded minor shocks occurred in 1636, 1858, 1863, 1883, 1907, 1911, 1918-19, 1923, 1925, 1930 and 1933-35. There are no records of any minor precursor shocks to the 1939 earthquake since the operation of the seismograph at Accra had been discontinued a few years previously on the grounds of economy; but between 1932 and 1935 cracks began to appear in substantial Government buildings in Accra and in the ground near the buildings. At the time Dr. Junner directed attention to the possibility of earthquakes occurring within the next 10-15 years. The earthquake of June 22, 1939, occurred at approximately 7.20 p.m. (G.M.T.) and was felt for about 20-30 seconds at Accra. There is no doubt that casualties were fewer than might have been expected from the severity of the shock since at the time many people were out of doors and there were no subsequent outbreaks of fire. The earthquake was felt by persons over an area of approximately 300,000 square miles and at places more than five hundred miles from Accra. As the epicentre was probably out to sea some twenty-five miles from Accra it is likely that it would have been felt over an area of 600,000 square niiles if the whole of the area had been populated land.