Alluvium

Alluvium (from Latin alluvius, from alluere 'to wash against') is loose clay, silt, sand, or gravel that has been deposited by running water in a stream bed, on a floodplain, in an alluvial fan or beach, or in similar settings.

[6] The present consensus is that "alluvium" refers to loose sediments of all types deposited by running water in floodplains or in alluvial fans or related landforms.

Drawing upon concepts from Roman law, Furetière defined alluvion (the French term for alluvium) as new land formed by deposition of sediments along rivers and seas.

With the rejection by geologists of the concept of a primordial universal flood, the term "diluvium" fell into disfavor and was replaced with "older alluvium".

The definition gradually expanded to include deposits in estuaries, coasts, and young rock of marine and fluvial origin.

Alluvium and adjacent constituents
Alluvium deposits in the Gamtoos Valley in South Africa
An alluvial plain in Red Rock Canyon State Park (California)
Alluvial river deposits in the Amazon basin , near Autazes, AM, Brazil . The seasonal deposits are extremely fertile and crucial to subsistence farming in the Amazon Basin along the river banks.