Cirque
Imagine a massive piece of ice grinding away at a layer of bedrock. This is what a glacier does to form a cirque. When it has finished working, a semi-circular bowl is left that resembles an amphitheatre. This is a cirque.
Arete
If you've ever seen a sharp-edged ridge, you've seen an arete. An arete forms when a glacier wears away its sides, sculpting a knife-edged ridge. The summit of Mount Oberlin is a perfect example of a prominent arete in Glacier National Park.
Hanging Valley
Below the arete on Mount Oberlin's summit is a hanging valley that overlooks the actual valley floor below. A hanging valley is created when a small glacier erodes a mountain. The one on Mount Oberlin resembles a large bowl, perched high above the park.
Paternoster Lakes
Lakes formed by glaciers form in U-shaped valleys and form in chains called paternoster lakes. Glacier National Park has great examples of these formations. A popular example is the chain formed by Grinnell, Josephine and Swiftcurrent Lakes.
Moraine
Boulders, rocks, silts and other residues left behind by a glacier are called a moraine. Moraines are sub-categorized as end, ground, lateral, and medial moraines. These categories refer to the location where the residue is deposited; for example, a lateral moraine has residue deposited on the sides of the glacier.
