Faulted Debris Flow Earthquake
Archaeological and structural evidence from the Berniki
Theater and the South Gate area at
Tiberias indicates
significant earthquake damage that occurred sometime
between the 7th and 10th centuries CE, probably during one of the
749 CE Sabbatical Year Earthquakes.
Ferrario et al. (2020) identify a
terminus ante quem
of “not later than the 8th–11th century CE” for the
damaging event at the theater. This constraint is based
on structures of the
Fatimid–
Abbasid quarter that were
built directly on top of the theater and the
debris-flow deposits that buried it. These later buildings followed
a plan similar to the underlying theater.
The overlying Fatimid–Abbasid structures were removed
during excavation to expose the
Roman theater. Photographs
taken prior to their removal show that these later
structures exhibited no visible faulting, damage, or
deformation. According to
Ferrario et al. (2020), the earthquake damage was
“limited to the
Roman-age flooring and to the debris
flow sediments above it."
An earlier chronological constraint comes from the South
Gate area of Tiberias, where a deformed Byzantine wall
and the collapse of a
vaulted structure were observed.
The wall belongs to the city fortifications attributed to
the reign of
Justinian I, who ruled from 527–565 CE.
Procopius (c. 500-565 CE) reports in
Book V, Chapter IX of
On the Buildings of Justinian that Justinian constructed
“the wall of Tiberias,” and a marginal note in the
translation of the text dates this work to about 550 CE.
The collapsed vault associated with the deformation was
dated to the
Umayyad period by
Hartal et al. (2010), while structures constructed
above the collapse were assigned to the
Abbasid period.
Taken together, these observations constrain the
archaeoseismic damage at the Berniki Theater and the
South Gate sector to an interval between the 7th and
10th centuries CE. No radiocarbon dates were obtained
from the debris-flow deposits covering the theater, and
although a trench was opened near the South Gate, it
could not be deepened below levels of the 11th century CE
because human remains were encountered.