Question

How do sea waves modify the coastal regions?

Answer 1

Sea waves are an important agent of erosion along with currents, storms and tides. But this erosion is mainly confined to sea coast only and results into several coastal landforms. Some of them can be understood with following points:

1. Sea caves: Due to the action of strong waves, the rock surface gets disintegrated and develops cavities. With time and continuos action of these sea waves, such cavities get enlarged and mould into cave-like structures referred to as sea caves.

2. Sea arch: When a single standing rock in the sea is faced with strong waves, its middle portion gets eroded. This forms a door passage or an arch-like structure known as sea arch.

3. Stacks: As a result of the continuos action of sea waves over a long period of time, the roof of the sea arch also gets eroded leaving behind only the pillars known as stacks.

4. Sea cliff: When a sea wave strikes the surface of rock facing the sea for a long period, it erodes its roughness making it very sharp and steep towards the side of the sea. These landforms are referred as sea cliffs.

5. Beach: When the sea is calm, it deposits the silt, alluvium, sand and gravel that it brought with itself along the seashore. This results into the formation of long beaches.

6. Lagoon: A partially enclosed lake formed when the sea water is trapped between the sea coast and sand bar is known as a lagoon. (Sand bars are the landforms formed inside the river at the mouth by deposition of a large volume of sand, pebbles, alluvium and water.)