Deltas

What are deltas? Deltas are flat, low areas of land that form at the mouth of a river, where the river flows into a quiet body of water. Deltas form when a river carries more sediment than can be washed away by tides and waves. At the mouth of the river, the velocity decreases suddenly and so sediment is deposited.

World’s major deltas Yukon Rhine Hwang Ho Colorado Nile Ganges Yangtze Mississippi Orinoco Niger

Types of delta The name delta comes from the Greek letter delta (Δ), due to the triangular shape. But shape depends on sediment load, discharge, wave power and tidal range. There are 3 main types of delta: Arcuate deltas Bird’s foot deltas Cuspate deltas

Arcuate Deltas

Bird’s Foot Deltas

Cuspate Deltas River Channel Sediment deposits Wave dispersal