Purported archaeoseismic evidence has been reported from the nothern part of Gezer in Field XI. Indicators include a debris layer, displaced ashlars, through-going joints, and tilted, folded, and displaced walls.

Younker (1991) noted that an excavation against the outer face of Macalister’s “Tower VII” revealed a debris layer consisting of fallen ashlar blocks in a bricky fill containing 8th century BCE sherds above 10th-century BCE fill. He suggested that the debris layers may be evidence of both an earlier 8th century earthquake and a later 8th century B.C. Assyrian destruction. At Macalister’s “Tower VI,” Younker (1991) described displaced ashlars, through-going joints, and tilted walls. The wall’s original 10th-century BCE construction and its 9th/8th-century BCE remodel—which “inserted” ashlars as an offset into the upper courses—both appear to have been destroyed sometime in the 8th century BCE. Dever (1993) reported that the top of the inner face of a long section of the outer wall east of “Tower VI” was displaced 50 cm or more outward, and bowed out in a sweeping curve. He added that the tops of the wall stones were tilted down-slope at an angle of ca. 10–20 degrees. He also uncovered a tilted Iron Age wall superimposed on a Late Bronze II wall.

Younker (1991) argued that the damage was caused by an earthquake rather than slow soil creep, emphasizing that “several sections of the Outer Wall had been clearly displaced from their foundations by as much as 10 to 40 cm,” that these “wall sections were all severely tilted outward toward the north,” and that intact portions of upper courses “had fallen backwards into the city,” not downslope beyond the wall. He further observed that the southwest corner of the 9th/8th-century BCE ashlar insert had shifted off its cornerstone, which had been split longitudinally because of the great pressure created by the lateral movement of the upper courses. The same pressure produced fissures in the ashlar stones that penetrated through several courses.

In contrast, Fantalkin and Finkelstein (2006: 22 n. 3) argued that the observed tilts could result from long-term fill pressure on the city wall, which lies along the mound’s slope. They emphasized that the sections showing deformation were part of a substructure buried from the outset and thus unlikely to have been affected by a quake, and that no evidence for a seismic event has ever been found in any free-standing building at Gezer.

The chronology of Gezer’s outer walls remains debated, focusing mainly on whether construction occurred in the 9th or 10th century BCE. Ortiz and Wolff (2017: 7) note that scholars are divided as to whether there are two phases (tenth century and a later rebuilding during the ninth or eighth centuries B.C.E.) or only one.

Deformation Map - Click on image to open in a new tab - Modified by JW from Plate 19 of Younker (1991)