Anonymous
Anonymous asked in Science & MathematicsEarth Sciences & Geology · 1 decade ago

# What happens to the soil that washes into river?

Relevance

Soil that is washed into a river will form many things. First the soil will more then likely be washed down stream. If the flow of water is strong enough to wash it into a stream, then more then likely the stream is fast enough to push the soil(which is sediment) down stream.

Soil is comprised of serveral things including organic matter, coarse grained sediment (sand sized) and clay and silt size sediment. Once in the stream the soil will be seperated into the different parts. The larger heavier parts will not travel as far as the smaller parts (things like silt and clay).

While entrained in the stream the different parts of the soil will be carried downstream until the velocity of the stream can no longer hold it. The particles will then begin to be deposited on the stream bottom beggining with the large. The particles continue until the stream reaches either the ocean or a lake. We will assume your stream is flowing to a lake. Once the sediment reaches your mythical lake, then usually the only things left still in the stream will be silt and clay particles from the soil. These silt and clay sized particles will then begin to settle out to the bottom of the lake.

Once everything is deposited two things can happen. The sediment from your soil can be compacted or cemented, or both can create a rock (sandstone, siltstone, mudstone, ect) or the sediment can be mixed again with more sedimentand organic matter, and form soil again. (thus the process could be repeated)

• Bomba
Lv 7

If the river is moving rapidly the soil will mostly be carried along until a slow region is reached and it will settle as sediment. As the slow region fills, some will be reentrained during floods of peroids of unusual rainfall. Sooner or later it will reach a lake or the ocean. The re-transport of sediments is what created the river deltas.

When large dams are built the normal cycle of deposit and reenrtainment is disturbed and eventually the lake formed by the dam will begin to fill with silt. The spillwaters are located at the dam, not where the deposits are laid down upstream.

the soil could combine with other small peices of rock to form a sedimentary rock.

it could also host underwater plants

or you could just end up with mud : D

it goes to the bottom of the river ya think? sediment!