For the Love of Geography – Cirque

A cirque is a semicircular shaped bedrock feature high on mountainside partially surrounded on three sides by steep cliffs. Cirques are created by the advancing and retreating of glaciers. The basin becomes deeper and wider in diameter each year as it continues to be eroded. An interesting feature of a cirque is the tarn or glacial lake which results from melting glaciers.

 GT_tetons_glacier-moraine

Cirque, Grand Teton, Wyoming

Sometimes multiple cirques will form, the rock in between is an arête, a steep ridge dividing the two cirques. When three cirques form the result is a glacial horn (or pyramidal peak) such as the Matterhorn in the Alps or Irene’s Arête in the Tetons.

GT_mt moran12

Cirques and arêtes, Mount Moran, Wyoming

Photos taken at Grand Teton National Park

Advertisements