ALLUVIUM, alluvial deposits (from the Latin word "alluvio", which means deposit or alluvium * EN: alluvium, alluvial deposit; DE: Alluvium, Alluvialboden; FR: alluvion; ES: depositos aluviales, aluvion; RU: аллювий),

1) the depositions of the water flows (rivers, brooks), which are forming the channels, floodplains and terraces of the river valleys. There are naturally combined in the alluvium of the lowland rivers the channel alluvium, which is deposited in the shifting channel of the flow (the cross-bedded sandy loams, sands, and gravel), the floodplain alluvium, which is accumulated over the channel alluvium during the floods, with the fine subparallel and distorted wavy stratification (mainly the sandy loams and loams), and the ancient alluvium, which is deposited in the oxbow lakes (mainly the sandy loams, loams, and clays, with the wavy and horizontal stratification, which are rich in the organic matter).

The composition and structure of the alluvium vary significantly, depending on the size and water regime of the flow, on the relief of the drainage basin, and on the rocks, which compose the drainage basin. For example, there dominate in the alluvium of the mountain rivers the boulder-pebble channel alluvium, with which there are associated the placer deposits of the gold, platinum, tin, and other heavy minerals (see the "Alluvial placer deposits" article), with the gravel-sandy channel alluvium of the rivers of the low mountains and plains, which contains the deposits of the building sand and gravel.

2) They often name as the alluvium in the foreign literature any deposits of the flowing waters, including the proluvium and deluvium (talus deposit).