Posidonius Quake

Second Century BCE

by Jefferson Williams

Introduction     Textual Evidence     Archeoseismic Evidence     Tsunamogenic Evidence     Paleoseismic Evidence     Notes     Paleoclimate - Droughts     Footnotes     References


Posidonius, as quoted by Strabo and Seneca, described an earthquake which "swallowed up a city above Sidon" and destroyed two-thirds of Sidon itself. The destruction in Sidon is described as occurring slowly such that loss of life was minimal. This may describe a slow moving displacement of structures which was induced by liquefaction. Shaking is described as moderate in Syria. It was likely stronger in Phoenicia. This earthquake is not well dated. Ambraseys (2009) estimated that it occurred in the second century BCE. Although most catalogs (including Ambraseys (2009)) classify this earthquake with a date of 199 or 198 BCE, we agree with Ambraseys (2009) that this earthquake is not well dated and can be best described as an event that probably happened around 199 BCE. A few earthquake catalogs date this earthquake to 525 BCE. It is not currently understood how anyone came up with a 525 BCE date. See the Notes section of this entry for more details on the 525 BCE date.

Textual Evidence

Posidonius quoted by Strabo

Strabo (~ 64 BC – ~ 24 AD), in his book Geographicum, using Posidonius (~135 BC – ~ 51 BC) as his source, reports an earthquake which destroyed two thirds of Sidon and was felt moderately over all of Syria. In Book I Chapter 3 Paragraph 16 one can read:
And in Phoenicia, says Poseidonius, on the occasion of an earthquake, a city situated above Sidon was swallowed up, and nearly two-thirds of Sidon itself was engulfed too, but not all at once, so that no considerable destruction of human life took place. The same operation of nature extended also over the whole of Syria, but with rather moderate force; and it also passed over to certain islands, both the Cyclades and Euboea, with the result that the fountains of Arethusa (a spring in Chalcis) were stopped up, though after many days they gushed up at another mouth, and the island did not cease from being shaken in some part or other until a chasm in the earth opened in the Lelantine Plain and vomited forth a river of fiery lava.
This earthquake is not well dated. As noted by Ambraseys (2009) and others, Book I Chapter 3 is not ordered chronologically. It is ordered thematically. However, because the account of an earthquake near Sidon is (mistakenly) conflated with earthquakes in the Cyclades, Euboea, and Chalcis along with a volcanic eruption in the Lelantine Plain, the dates of these alleged events might help estimate the date of the Posidonius Quake near Sidon. Ambraseys (2009) suggests that the earthquake in the Cyclades refers to an earthquake that caused damage in the nearby Dodecanese which he dates to the second century BCE based on several inscriptions reported by Roberts (1978).

Archeoseismic Evidence

Tsunamogenic Evidence

Paleoseismic Evidence

Bet Zayda

Wechsler at al. (2014) records event CH4-E6 (modeled age 392 BCE – 91 CE) in paleoseismic trenches at Bet Zayda just north of the Sea of Galilee (aka Lake Kinneret).

Bet Zeyda Earthquakes
Figure 9. Probability density functions for all paleoseismic events, based on the OxCal modeling. Historically known earthquakes are marked by gray lines. The age extent of each channel is marked by rectangles. There is an age uncertainty as to the age of the oldest units in channel 4 (units 490-499) marked by a dashed rectangle. Channel 1 refers to the channel complex studied by Marco et al. (2005).

En Feshka

Kagan et. al. (2011) identified a 2 cm. thick Type B seismite at 425.0 cm. depth in En Feshka which they attributed to the Posidonius Quake of ~199 BCE. The 1σ date range was from 243-202 CE and the 2σ date range was from 288-183 CE.

Seismite Types are shown visually in Figure 2 and and are described in Table 1 of Kagan et al (2011) which is repeated below:

Type Description
A Intraclast breccia: Light and dark laminae “floating” in a dark matrix.
B Microbreccia: A light gray layer, seemingly homogeneous to the naked eye,
of intermediate color somewhere between the dark brown/gray detrital laminae
and the white/beige evaporitic laminae. Petrography shows this to be a mixture
of the evaporitic and the detrital material
C Liquefied sand
D Fold: Small-scale folds, where the amplitude is on the order of millimeters to a few centimeters
E Fault: Tiny faults, millimeter to centimeter scale throw

Nahal Ze 'elim

Kagan et. al. (2011) identified a 8 cm. thick Type A seismite at 552.0 cm. depth in Nahal Ze 'elim (ZA-2) which they attributed to the Posidonius Quake of ~199 BCE. The 1σ date range was from 260-190 CE and the 2σ date range was from 300-150 CE. Considering the distances involved, the Fortress at Arad Quake is a better candidate.


Kanari, M. (2008) examined rockfalls in Qiryat-Shemona which were attributed to earthquakes. Optically stimulated luminescence (OSL) dating was performed on soil samples beneath the fallen rocks. Although rockfalls were attributed to the Posidonius Quake (labeled 199 BCE), the error bars are so large that a number of seismic candidates are possible.

Qiryat-Shemona Rockfall dates from old GSI Report
Figure 4-7. Qiryat-Shemona OSL ages and suggested rockfall triggers. OSL age results for the past 8000 years in black circles with error bars; ages of earthquakes determined by Yagoda et al. (2007) in gray diamonds and by Kagan et al. (2005) in gray triangle; corresponding dates of earthquakes suggested as rockfall triggers in gray lines and labeled at top axis (see Table 4-2). QS-2 (55.7 +/- 7.6 ka) excluded from graph for very large uncertainty range
The criteria used by Kanari (2008) to identify historical earthquakes as triggering the observed rockfalls included:

(a) Estimated minimum MMI of IX
(b) Calculated Moment-Magnitude greater than or equal to 6.5
(c) distance to the site not exceeding 100 km.

Kanari (2008) surmised that these conditions satisfied Keefer (1984)'s upper limit for disrupted slides or falls triggered by earthquakes.


Posidonius quoted by Seneca

Seneca (4 BCE - 65 CE) wrote Questionaes Naturales in Latin. His section on Earthquakes is titled Book IV - De Terrae Motu (concerning earthquakes). At the beginning of the chapter he mentions the then recent Campanian Earthquake of 62/63 CE [1] indicating that this section was put in final form between 62/63 CE and his forced suicide in 65 CE. In Chapter XXIV of Book VI (p.256), one can read:
Thucydides tells us that, about the time of the Peloponnesian War, the island of Atalanta, either wholly, or, at any rate, for the most part, was swallowed up. You may take Posidonius for witness that the same thing happened to Sidon.
Questionaes Naturales in its original Latin can be accessed here.

525 BCE Catalog Entries

The source for the 525 BCE entry in later catalogs is probably Sieberg (1932b) who describes earthquake damage in Sidon, a tsunami, and the quake being felt in the Cyclades and Euboea. Although Sieberg (1932b) never cited sources, his damage description indicates his source was Strabo quoting Posidonius, possibly Seneca and/or another source, and perhaps a little embellishment. Other catalogers (e.g. Ben-Menahem(1979), Ben-Menahem(1991), Antonopoulos (1979), Plassard and Kojoj (1981), and Sbeinati et. al. (2005)) more or less repeat Sieberg's description for 525 BCE. Sbeinati et. al. (2005) appears to list this same earthquake twice in 199 BCE and 525 BCE. Obviously, this double date is an error. How Sieberg (1932b) came up with a date of 525 BCE is currently a mystery. Migowski et al (2004) assigned a seismite at En Gedi to the 525 BCE date and Kagan et al (2011) assigned seismites at En Feshka to both 199 BCE and 525 BCE dates. Although their date ranges may be approximately correct, due to the distance involved, we believe that their quake assignments are wrong for both dates (199 BCE and 525 BCE). Neither Ambraseys (2009) nor Guidoboni et. al. (1994)) have an entry for a 525 BCE earthquake.


Posidonius was a celebrated Greek polymath originally from Apamea, Syria. He is thought to have authored over 20 works none of which have survived intact. All that have been found are fragments. Some of his work, however, survives as quotations by other authors foremost among them Strabo and Seneca.

Paleoclimate - Droughts


[1] See Williams (2006) p. 125 footnote 1 for a discussion on possible dates of this earthquake.


Ambraseys, N. (2009). Earthquakes in the Mediterranean and Middle East: A multidisciplinary study of seismicity up to 1900.

Guidoboni, E., et al. (1994). Catalogue of ancient earthquakes in the Mediterranean area up to the 10th century. Rome, Istituto nazionale di geofisica.

Kagan, E., et al. (2011). "Intrabasin paleoearthquake and quiescence correlation of the late Holocene Dead Sea." Journal of Geophysical Research 116(B4): B04311.

Kanari, M. (2008). Evaluation of Rockfall Hazard to Qiryat Shemona: Possible Correlation to Earthquakes. Department of Geophysics and Planetary Sciences. Tel Aviv, Israel, Tel Aviv University: 135.

Wechsler, N., et al. (2014). "A Paleoseismic Record of Earthquakes for the Dead Sea Transform Fault between the First and Seventh Centuries C.E.: Nonperiodic Behavior of a Plate Boundary Fault." Bulletin of the Seismological Society of America.

Ancient Texts

Strabo, Geography

Posidonius, Fragmenta, ed. W.Theiler, Berlin-New York 1982. - Guidoboni's source

Posidonius, et al. (2005). Posidonius: Volume 1, The Fragments, Cambridge University Press

Seneca, Questionaes Naturales

Thucydides, Peloponnesian War