July 9, 551 Earthquake: Bayrut (Beirut), Egypt, Iraq, Saudi Arabia, Lebanon

Ref #3845:

551 July. 9 Dead Sea. A large earthquake in Palestine was strongly felt in Alexandria, where it caused panic but no damage. For the Nile Delta, which was considered to be almost free of earthquakes, this was unprecedented. The shock was felt throughout Palestine, Arabia, Phoenice and Lebanon as far as Antioch, and was associated with a seismic sea-wave on the coast of Phoenice. Modern writers place the epicentral region of this event offshore from Lebanon. This is due to the bias of information from the more populous coastal region. The data available to us, however, suggest an epicentre in the Jordan rift valley.

Ref#12645:

The exact date of this event is doubtful, and still not very clear. The earthquake destroyed several cities in Maritima (modern Lebanese coast) Moreover, there is a 6th/7th century AD source (De Fragmentis Historicis Tuscolanis) added that 101 towns, not named in the source but located in the vicinity of these cities, fell down, and a great myriad of men and animals were killed in them.

In Berytus, most of the buildings including the famous structures fell down with the loss of a great number of people under the debris [Agathias Scholasticus]. The Bishop of Beirut (an eyewitness of the earthquake) said that there were 30,000 deaths due to the earthquake, except the foreign residences [Antoninus Placentinus]. This figure is probably reasonable for a city that was flourishing to the extent it was called pearl of the Phoenician coast at that time..

The city of Sidon suffered with a large number of deaths [John Malalas]. The cities of Byblus, Tyrus and Tripolis were also destroyed with their inhabit ants [John Malalas, Antoninus Placentinus, De Fragment is Historicis Tuscolanis, Chronicon pseudo-Dionisyanum]. Tyre was also destroyed with its inhabitants [John Malalas, De Fragment is Historicis Tuscolanis, Chronicon pseudo-Dionisyanum.] A similar fate befell the town of Trieris [Antoninus Placentinus] , modern Shikk

The total number of deaths is rather difficult to evaluate. However, as a result of the earthquake side effects (tsunami and fires) we believe that a myriad of people were killed along the Lebanese coast, particularly in Beirut.

Location of three new affected sites: these are the island of Aradus (modern Arwad), the towns of Trieris (modern Shikka) and Sarepta (modern Sarfand)

Assessment of the average surface-wave magnitude of the earthquake (Ms), to be of the order of 7.1-7.3.

Ref#9116:

Damage extended along 100 km of the littoral of Galilee and Phoenice Maritima, where towns and villages on the coast were ruined by two successive earthquakes and the seismic sea wave that followed the first quake.

Beirut seems to have been the worst hit. It was badly damaged by the earthquake and a sea wave, but most of the destruction seems to have resulted from the ensuing fire, which apparently raged for two months. Buildings and works of art were lost.

In addition to noting that Tripoli and Byblus collapsed, and that at least 30000 people died in Beirut, he mentions that a place called Trianis collapsed in the earthquake.

[...]destructive fire in Berytus after the earthquake