Stream and River Deposits

As you possibly already know, the ’s surface is constantly eroded by flowing .

After rivers erode rock and soil, they deposit (drop) their load downstream.

This process is known as deposition. Rocks and soils deposited by streams are known as “sediments”.

Rivers and streams deposit sediment where the speed of the current decreases.

In rivers, deposition occurs along the inside bank of the bend, while erosion occurs along the outside bank of the bend, where the flows a lot faster.

Sometimes, heavy minerals are deposited at the points in the that the current slows down.

This kind of sediment is called a “placer deposit”, which was a hot-spot for .

During the rush from 1848-1855, many thirsty -seekers panned for in the placer deposits of rivers.

In , the Nile slows when it empties into the Mediterranean , and as this current slows, it forms a delta.

A delta is a fan-shaped mass of material deposited at the mouth of a stream.

A delta usually forms on a flat surface and is made out of mud.

These muddy deposits create a new land and cause the coastline to grow, thus, making the world’s deltas home to a diversity of plants and life.

In the US, the watershed has formed the Delta, which flows into the Gulf of .

A lot of the mud particles made their journey down to the Gulf of from areas upstream, such as Montana, , , and Illinois.