Amos’s earthquake: An extraordinary Middle East seismic event of 750 B.C

Abstract

Widely separated archaeological excavations in Israel and Jordan contain late Iron Age (Iron IIb) architecture bearing evidence of a great earthquake. Masonry walls best display the earthquake, especially walls with broken ashlars, walls with displaced rows of stones, walls still standing but leaning or bowed, and walls collapsed with large sections still lying course-on-course. Debris at six sites (Hazor, Deir ‘Alia, Gezer, Lachish, Tell Judeideh, and ‘En Haseva) is tightly confined stratigraphically to the middle of the eighth century B.C., with dating errors of ∼30 years. Biblical and post-biblical sources indicate a single, regionally extensive earthquake in the year 750 B.C. The epicenter was north of present-day Israel, probably in Lebanon, as indicated by the southward decrease in degree of damage at sites in Israel and Jordan. A large area of the ancient kingdoms of Israel and Judah was shaken at Modified Mercalli Intensity 9 or higher. The distance from the epicenter (north of Israel) to isoseismal VIII (south of Israel) was at least 175 km, but could have been as much as 300 km. The earthquake was at least magnitude 7.8, but likely was 8.2, the magnitude being estimated by scaling of isoseismal radii relative to smaller historic earthquakes in Israel and Lebanon. The M1 ≍ 8.2 event of 750 B.C. appears to be the largest yet documented on the Dead Sea transform fault during the last four millennia. This severe geologic disaster has been linked historically to a speech delivered at the city of Bethel by a shepherd-farmer named Amos of Tekoa. Amos's earthquake was synchronous with the introduction of “seismic theophany” imagery into Hebrew literature, with the appearance of the “Day of the Lord” eschatological motif, and with the explosive emergence of “writing prophets” in Israel.