THE 9 JULY 551 AD BEIRUT EARTHQUAKE,EASTERN MEDITERRANEAN REGION

Analysis of the Byzantine primary and secondary sources for identifying the historical earthquakes in Syria and Lebanon reveals that a large earthquake (M _s =7.2) occurred in July 9, 551 AD along the Lebanese littoral and was felt over a very large area in the eastern Mediterranean region. It was a shallow-focus earthquake, associated with a regional tsunami along the Lebanese coast, a local landslide near Al-Batron town, and a large fire in Beirut. It caused heavy destruction with great loss of lives to several Lebanese cities, mainly Beirut, with a maximum intensity between IX-X (EMS-92). The proposed epicentre of the event is offshore of Beirut at about 34.00°N, 35.50° E, indicating that the earthquake appears to be the result of movement along the strike-slip left-lateral Roum fault in southern Lebanon.