wavecut

Wavecut is a term used in coastal geomorphology to describe features formed by the erosive action of waves at the base of cliffs. The most common manifestations are wave-cut cliffs, formed when the sea undercuts the rock at the cliff base, and wave-cut platforms, flat, bench-like surfaces that extend into the sea at low tide.

Formation occurs as hydraulic action and abrasion create a notch at the cliff base. Continued undercutting destabilizes the overlying rock, which eventually collapses, causing the cliff to retreat landward. Repeated cycles of erosion and collapse over long periods produce an inland-facing cliff and a corresponding platform at the foot of the cliff. The platform may be exposed at low tide and can extend hundreds of metres offshore as a submerged or emerged terrace. The exact shape and extent depend on rock type, wave energy, tidal range, and relative sea level. Shifts in sea level or tectonic uplift can expose relict (emerged) platforms or leave submerged ones.

Wave-cut features are important records of past coastal dynamics and sea-level history. The term often accompanies related features such as wave-cut notch and coastal terraces, which reflect similar processes. On some coastlines, subsequent sedimentation or tectonic activity can create staircases of terraces or isolated benches linked to the original wave-cut systems.