Historical Seismicity of Egypt

The historical earthquakes that have been felt in Egypt were compiled from Arabic documents and earlier earthquake catalogues. About 83 earthquakes were found during the period from 2200BC to 1899AD. The time distribution of these earthquakes shows that, only seven earthquakes have been reported in the period before Christ (BC). Up to the end of the ninth century the secular number of reported earthquakes fluctuates between zero and three. A relatively high number (eight) of earthquakes has been reported in the tenth century. In the eleventh and twelfth centuries (Fatimid period) a dramatic decline in the earthquake number has been notified. After this decline the number of earthquakes re-increased up to the fifteenth and sixteenth centuries (Mamluk Period) reaching a relatively high value (ten). In seventeenth and eighteenth centuries, when Egypt was a province of the Ottoman Empire, another dramatic decline has been realized. The reported earthquakes reach their highest number (seventeen) in the nineteenth century. The spatial distribution of historical earthquakes is relatively disagreeing with the epicentral distribution of recent earthquakes. The distribution of population in a narrow band along the Nile Valley and Delta creates challenging problems in locating and assessing the origin and true effects of historical earthquakes in Egypt. Earthquake epicenters are located almost exclusively in Cairo, the Nile Delta and the Nile Valley. Most earthquakes that affected these areas originated from epicenters at the subduction zone in the north and rifting zone in the east. Egypt has experienced damaging large earthquakes from the Hellenic Arc and eastern Mediterranean, as well as the Red Sea and its two branches, Gulf of Suez and Gulf of Aqaba. Earthquakes originated from local sources have also affected the country.