Rock glacier

The two known factors that must be present in order to create rock glaciers are low ice velocity and permafrost.

Periglacial rock glaciers require permafrost instead of glacial ice in order to form.

Some rock glaciers can reach lengths of three kilometres (2 mi) and can have terminal embankments 60 m (200 ft) high.

Flow features on the surface of rock glaciers may develop from: Their growth and formation is subject to some debate, with three[clarification needed] main theories: Rock glaciers may move or creep at a very slow rate, in part dependent on the amount of ice present.

[7] Rock glaciers in the Chilean Andes help supply the water for much of Chile, including the capital of Santiago.

In 2004, protesting irrigation farmers and environmentalists changed rules so new mining projects can no longer damage or alter rock glaciers in Chile.