Arce (2000:130) reports that the Umayyad Congregational Mosque at the Amman Citadel collapsed in the 749 CE Sabbatical Year Quakes. Structural damage included displaced column bases and dislocated foundations, which broke an adjacent water channel. Arce (2000) notes that the collapse resulted not only from the seismic shock but also from poor construction techniques, particularly inadequate fill compaction and unstable foundation design.

Arce (2000) dates the mosque to the Umayyad period based on construction techniques (lime-with-ash mortar, chip jointing), layout parallels with early Islamic hypostyle mosques, and its integration into the broader palatine complex. No direct inscriptions or coins were used to date the mosque itself, but associated architectural style and stratigraphy firmly place it in the early 8th century. The mosque was never rebuilt and was converted into residential use in the Abbasid period, providing an Abbasid terminus ante quem for its destruction.

Arce (2000:135–140) also reports that multiple architectural elements were found in the 749 CE earthquake debris, including decorative cornices, fragments of façade decoration, niches, and colonnette panels. Four niche fragments displayed trefoil , vegetal , and composite tree motifs, with several pieces identified in undisturbed collapse layers along the west street/ziyada.

These smaller-scale niches differ from standard Umayyad assemblies by lacking structural interlocking elements and being designed for close viewing. Arce (2000) concludes they likely came from the lateral façades or interior of the mosque. Their form lacked the mechanically integrated joints found in more robust ashlar masonry, which may have contributed to their vulnerability during the collapse.

Additional evidence of interior damage includes fragments of carved stucco retrieved from the mosque’s courtyard and cisterns , indicating that while exterior façades used carved stone, the interior decoration relied on more fragile materials. A marble slab with a carved Kufic inscription—painted in red and blue—was also found in the collapsed debris at the mosque’s west wall. The reverse side bore a rougher reused inscription. Other graffiti found on steps include fragmentary invocations of the divine name "Allah" and phrases such as "Allah ’umma" and "Illa[..]".