Outwash fan

An outwash fan is a fan-shaped body of sediments deposited by braided streams from a melting glacier.

Outwash fans typically form from valley glaciers flowing downhill in the mountains.

Thus, outwash fans are usually found in colder environments where glaciers are more prevalent and are often located where a valley or canyon empties out onto a flatter wider plain.

Because the sediments rely on melt water for transportation, the ablation rate directly affects the development of an outwash fan.

[1] Minor fans, unlike the more extensive outwash fans that transport larger sized material by high energy streams from underneath the glacier, are mainly made up of fine grained sediments (i.e. sand) and are deposited by low energy streams that drain debris along the glacier's surface.