How does gravity contribute to the collapse of sea cliffs?

Gravity is a fundamental force in the evolution of coastal landforms, specifically regarding the stability of sea cliffs. While wave-induced erosion typically attacks the base of a cliff, creating a notch and removing support, it is gravity that acts as the primary driver for the subsequent collapse of the unsupported rock mass above.12

This process is a form of mass movement, where gravity pulls loosened rock and debris down the slope. As waves undercut the base, the cliff face loses its structural equilibrium. Gravity then forces the overhanging or weakened sections to fail, resulting in rockfalls or other forms of landslides that deposit material at the cliff's base. Consequently, gravity is the essential mechanism that translates the localized damage caused by waves into the large-scale retreat and structural failure of the cliff face.321