May 20, 1202 Tsunami: Southwestern Syria

Gigantic waves rose up in the sea between Cyprus and the coast of Syria. The sea withdrew from the coast, ships were hurled on to the eastern coast of Cyprus, fish were thrown on to the shore, and lighthouses were damaged. (reference #10420)

The tsunami followed a destructive earthquake that affected the oriental Mediterranean coast and hinterland of what are now Lebanon, Syria, and Israel. Surface rupture along the Yammouneh fault (Daëron et al., 2004, 2005; Nemer et al., 2008) and the Jordan Gorge segment of the DST (Marco et al., 1997, 2005; Ellenblum et al., 1998) indicate that this was an on-land earthquake. It is therefore possible to assume that one or more seismogenically-triggered sub-marine landslides offshore of the Levant coast generated the tsunami. An estimated magnitude of this event was given by Ambraseys and Barazangi (1989) as Ms = 7.5, Ambraseys and Jackson (1998) determined this as a large event, and Ambraseys (2006) gave an estimate of Ms = 7.2. (reference #10416)

The occurrence of a seismic sea wave between Cyprus and the Syrian coast, 50–100km from the epicentral region, is difficult to understand. It may be explained by invoking the generation of a large-scale subaqueous slide from the continental margin of Syria by the earthquake. North of Acre the continental shelf narrows to a few kilometres and off the coast of Lebanon the continental slope steepens from near Acre northwards to an average of 10◦. Under these circumstances, the principal cause of a seismic sea wave could be submarine sliding and slumping. The whole of that coast is certainly prone to slumping because of evaporites in the sedimentary section. (reference #9116)

Reference #9275 lists alternative dates associated with event: 2 June 1201, 21 May 1201, early morning, 22 May 1202/1222