Marine Landform: Depositional Landforms

Beaches

  • Beaches are made up of eroded material that has been transported from elsewhere and then deposited by the sea. 
  • For this to occur, waves must have limited energy.
  • Constructive waves build up beaches as they have a strong swash and a weak backwash.
  • Sandy beaches are usually found in bays where the water is shallow and the waves have less energy. 
  • Pebble beaches often form where cliffs are being eroded, and where there are higher energy waves.

Spits and Hooks

  • A spit is an extended stretch of sand or shingle jutting out into the sea from the land. Spits occur when there is a change in the shape of the landscape or there is a river mouth.
  • A shorter spit with one end curved towards the land is called a hook.

Bars and Lagoons

  • The longshore currents, tidal currents and the shore drift deposit rock debris and sand along the coast at a distance from the shoreline. The resultant landforms which remain submerged are called bars. 
  • The enclosed water body so created is called a lagoon.

Barrier

  • It is the overwater counterpart of a bar.

Tombolos

  • A tombolo is a sandy isthmus which connects islands to mainlands.

Dunes & Dune Belts

  • With the force of on-shore winds, a large amount of coastal sand is driven landwards forming extensive marine dunes that stretch into dune belts.
  • For example – The Coastal Red Sand Dunes is also known as ‘Erra Matti Dibbalu’.

This entry was posted in General Studies 1, World Geography. Bookmark the permalink.