Waves are the major cause of erosion along the coast. Waves shape the coast through erosion by breaking down rock and moving sand and other sediments. One way waves erode the land is by the impact. Large waves hit rocks with lots of force. The energy in waves can break apart rocks. Over time waves make small cracks bigger. Eventually, the wave causes the rock to chip off. Waves can also erode rock by abrasion. As a wave comes to shallow water it picks up sediment. Once the wave crashes against land the sediment wears the rock down.
