The formation of glaciated upland features
Erosion processes form corries, ar锚tes and pyramidal peaks
Corries
A A bowl-shaped hollow area formed by glaciation, sometimes containing lakes or 'tarns'. Corries are also known as cirques or, when found in Wales, cwms. is an armchair shaped hollow high on a mountain with steep back and side walls. Snow gathers in mountain The dip in a mountain where snow and ice gather., especially north facing hollows, where there is more shade. This snow builds up and compacts to ice. The action of The force of attraction between all objects. The more mass an object has, the larger the force of gravity it exerts. means the ice moves downhill.
As it travels, ice sticks to the back walls and plucks rocks from the surface. Rocks on the back walls are also loosened by freeze-thaw action. A gap between the wall and the ice develops, called a A gap between the back wall of a corrie and the ice..
Ice moving with loose rock acts like sandpaper and deepens the hollow by abrasion. Most erosion occurs where the weight of the ice is heaviest. Stones frozen in the base of the ice grind or abrade the corrie base, deepening it.
Ice in a corrie has a The circular movement of a glacier inside the hollow of a corrie. movement which means that the front of the corrie is less The wearing away of the landscape. and a lip forms. The glacier retreats and melts, often leaving a A small lake found inside a corrie (also known as a corrie loch)./A small lake found inside a corrie (also known as a tarn). in the base of the corrie.