Deltas

What landforms can be created along the course of a river?

MIDDLE AND LOWER COURSE - Deltas

A delta forms when the river meets the sea and its velocity drops quickly. This reduction in velocity means that the river load is deposited at the mouth of the river. If the river is able to deposit faster than the sea can erode material then a delta will form. Deltas have very fertile soil and tend to be excellent for farming.

Other Definitions of Delta: 

"Most simply, deltas are landforms that develop wherever a river enters a large body of water—whether ocean, lagoon, or even lake (yep, there are inland deltas)—and deposits sediment more rapidly than can be eroded. Over time, the accumulation of sediment—usually sand, silt, and clay—cause the shoreline to advance, effectively building new land."  Porous Places

The Formation of a Delta

A Delta

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AS Physical Geography - Deltas

Questions on Deltas

Explain how a delta is formed? (5 marks)

Deltas are formed at the end of rivers (river mouth) as it flows into the sea

Rivers carry a lot of sediment (mud)

The river flows into a calm sea

This slows the river down

Which makes the river drop its sediment

This deposited sediment builds up over years creating a delta

The river is forced to split up

The smaller rivers made by deltas are called distributaries

Examples of Deltas are Nile Delta, Ganges Delta