Final answer:
Sea cliffs are formed predominantly by erosion, as the action of waves erodes softer coastal materials and leaves behind more resistant rock formations, leading to the creation of these stark and picturesque landforms.
Step-by-step explanation:
Sea cliffs are coastal landforms formed predominantly by erosion.
Coastal erosion is the process where strong waves strike the coastline, gradually carving out features such as cliffs, caves, and arches. Factors including wave direction, wind energy, and rock type all contribute to the erosional patterns seen along coastlines. Over time, the relentless pounding by waves erodes the softer material along the shore, leaving behind the more resistant rock as sea cliffs.
These vertical or nearly vertical rock exposures are a clear indicator of erosive forces at work, with waves attacking the base of the cliff to form a notch that undercuts the rock. As the rock above the notch becomes unsupported, it can collapse, leading to the cliff receding landward. This process creates a dynamic, constantly changing coastline shaped by the natural forces of water and wind.