Deltas are landforms which form when rivers, carrying sediment, empty into larger bodies of water such as seas, oceans or other larger rivers. Deltas may also more rarely form where rivers emerge from mountains into dry interior basins, such as the Okivango Delta in Kenya. The landforms often form a triangular shape, after which the deposits are named (for the Latin upper case letter Delta, )

Deltas are important in the creation of new land along coastlines, helping reshape and replenish them with new sediment. The mixing of fresh river water and salty ocean water often creates unique ecosystems that support rich and diverse plant and animal life.

Deltas are further shaped by both onshore processes, such as the amount of sediment in water, and volume of water, and slope (speed/power) of the land over which the river courses, versus offshore processes, such as waves, tides and storms. All of these forces help shape the coastlines near rivers.

Example of A Delta:   Ganges Delta, India 

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