How do waves erode bedrock along a rocky coast?

Waves erode bedrock along rocky coasts primarily through three mechanical processes:

• Abrasion: This is often considered the most significant erosional activity. Suspended sediment particles, such as sand, pebbles, and larger rock debris, are agitated by wave action and dragged back and forth against the bedrock. This functions similarly to sandpaper, grinding and wearing away the rock surface.12
• Hydraulic Action: Waves exert immense hydraulic pressure as they strike the shore. This force can break up bedrock simply through direct impact.12
• Quarrying: This process involves the hydraulic plucking of entire blocks of rock. It is particularly devastating to shorelines composed of highly jointed or bedded rock, where the force of storm waves can exploit existing fractures to dislodge large pieces of material.2

These combined actions often create a notch at the base of a cliff. As this notch deepens, the overhanging rock eventually collapses, causing the shoreline to retreat and leading to the formation of features such as wave-cut platforms, sea arches, and sea stacks.23