Delta is found in the old stage of a river. It is the triangular shaped landform made up of alluvial deposition in the mouth of the river. It is named after the fourth Greek alphabet called delta. Example, The Ganges Bhramaputra delta is the largest delta in the world.
Types of Delta: Delta is classified into the following based on the shape and kind of the load deposited by the river.
1. Arcuate Delta: A bowed or curved delta with the convex margin facing the body of water. It is also known as fan-shaped delta. Example, River Nile Delta in Egypt and Ganga Delta in India.
2. Estuarine Delta : it is formed at the mouth of submerged rivers depositing down the sides of the estuary. Example, Seine River of France.
3. Birds foot Delta: They are formed due to deposition of finer materials by river water. Deposited alluvial material divides the river into smaller distributaries. Such delta is also called as finger delta. Example, Mississippi river delta, the USA.
4. Lacustrine Delta: It is formed when a river flows into a lake. Example, Lough Leanne river delta, Ireland.
5. Truncated Delta: Sea waves and ocean currents modify and even destroy deltas deposited by the river through their erosional work. Thus, eroded and dissected deltas are called truncated deltas.
6. Abandoned Delta: when the river shifts its mouth, the delta already made is left abandoned. Such a delta is called abandoned delta. Example, Yellow river delta, China and the Western part of Ganga delta made by Hoogly river, India.
7. Cuspate delta is a tooth shaped delta formed when a single distributary flows through and deposits its load on its either side. Example, Tiber River of Italy