Anastasius Bibliothecarius described two earthquakes that occurred about a year apart. The years he assigned to both earthquakes appear inconsistent with archaeoseismic evidence from Bet She’an, which provides a terminus post quem of 749 CE for the first event. To avoid chronological confusion, these earthquakes are referred to by name rather than date.

The Holy Desert Earthquake is said to have struck first, at 10 a.m. in January of A.M._a 6238 (25 Mar 745 – 24 Mar 746 CE). Anastasius records it as a powerful earthquake in Palestine, by the Jordan, and in all of Syria in which thousands died – an innumerable multitude perished and churches and monasteries collapsed; it was worst in the desert of the Holy City [Jerusalem].

The Talking Mule Quake is described as striking Syria in A.M._a 6239 (25 Mar 746 – 24 Mar 747 CE). Anastasius reports that many died and that a spring [moved?]. He adds that in another place in the mountains, a village moved with its walls and homes intact for six Roman miles — likely an embellished version of a translational landslide, technically described as a block slide. He concludes that in Mesopotamia the earth split two thousand feet, and from the chasm emerged a white sandy soil and a spotless mule that spoke with a human voice and prophesied that Arab lands would be invaded by a foreign army – and this prophecy came true. Despite the fantastical appearance of an oracular Talking Mule — which became a very popular part of the story — the accompanying details of an earth fissure and sand boils remain seismically credible.