tion:Waves are IMPORTANT for building up and breaking down shorelines. Waves transport sand onto and off of beaches, transport sand along beaches, carves structures along the shore. The largest waves form when the wind is very strong, blows steadily for a long time, and blows over a long distance.The wind could be strong, but if it gusts for just a short time, large waves won’t form. Wave energy does the work of erosion at the shore. Waves approach the shore at some angle so the INSHORE part of the wave reaches shallow water sooner than the part that is further out. The shallow part of the wave ‘feels’ the BOTTOM first. This slows down the inshore part of the wave and MAKES the wave “bend.” This bending is called refraction.Wave refraction either concentrates wave energy or disperses it. In quiet water areas, such as bays, wave energy is dispersed, so sand is deposited. Areas that stick out into the water are eroded by the strong wave energy that concentrates its power on the wave-cut cliff.A wave-cut platform is the level area formed by wave erosion as the waves UNDERCUT a cliff. An arch is produced when waves erode through a cliff. When a sea arch collapses, the isolated towers of rocks that remain are known as sea stacks.