Alluvial plains

Alluvial plains are flat or gently sloping landforms created by the deposition of sediment over a long period of time by one or more rivers coming from highland regions, from which alluvial soil forms. A floodplain is part of the process, being the smaller area over which the rivers flood at a particular period of time, whereas the alluvial plain is the larger area representing the region over which the floodplains have shifted over geological time.

Formation

Alluvial plains are formed when rivers carry sediment from higher areas to lower areas during their flow. The sediment, known as alluvium, is deposited as the river loses energy upon reaching a flat area or a lake. Over time, the deposited alluvium accumulates and forms an alluvial plain.

Characteristics

Alluvial plains are characterized by rich, fertile soil, making them important areas for agriculture. The alluvium is typically unconsolidated, which means it is made up of a variety of materials, including fine particles of silt and clay, as well as larger particles of sand and gravel.

Examples

Notable examples of alluvial plains include the Indo-Gangetic Plain in India, the Nile River Valley in Egypt, and the Mississippi River Valley in the United States. These plains are often associated with some of the world's major rivers, reflecting their role in alluvial plain formation.

See also

• Floodplain
• River delta
• Sediment transport
• Erosion