How is a cirque formed?
A cirque appears on the face of a glacial mountain after years of erosion. The bowl-shaped indentation occurs as snow and ice accumulate and melt. Cirque formation signals the head or top of a glacial valley.FormationA cirque forms when accumulated ice and snow continuously melt and thaw on the glacier’s face, causing the mountain to erode and form a bowl. The process of erosion, which destroys the underlying rock, is known as scouring.LocationA cirque forms at the head of a glacial valley and near the top slope of a mountain. It is possible for a mountain to have more than one cirque.FeaturesA cirque is sometimes referred to as an amphitheater because of its distinctive three-walled shape.ShapeThe shape of a cirque resembles a circular bowl or basin about a quarter of the way down the face of the glacier. Repeated erosion causes the bowl shape to be quite deep.EffectsDepending on the depth of the cirque, a lake may form when the ice melts.
