Cirque (or Corrie) Llyn y Gadair, Gwynedd, Great Britain A bowl-shaped depression carved out of a mountain by an alpine glacier A steep-walled hollow, shaped like a half-bowl, formed by glaciation and frost wedging Cirques are found in mountainous regions populated with glaciers, or which have had a history of being glaciated
Cirque Contour lines suggest height mountains, where cirques are found
Ribbon Lake Long and narrow, finger-shaped lake, usually found in a glacial trough
Hanging Valley A shallow glacial trough that leads into the side of a larger, main glacial trough A valley most often formed as a result of glaciation, where a large glacier erodes a valley, at a perpendicular angle to the hanging valley, to a deeper extent. The result is that of a small valley intersecting a larger valley at an elevation noticeably above the bottom of the larger valley. Hanging valleys can be, but are not always, eroded by a glacier.
Hanging Valley animation http://www3.interscience.wiley.com:8100/legacy/college/strahler/0471238007/animations/ch20_animations/animation2.html Hanging Valley Stream leading to hanging valley Lake carved out by large glacier
Arête A sharp narrow ridge found in rugged mountains A sharp-edged ridge of rock formed between adjacent cirque glaciers An arête is a thin, almost knife-like, ridge of rock which is typically formed when two glaciers erode parallel U-shaped valleys. The arête is a thin ridge of rock that is left separating the two valleys.
GribGoch, Snowdia National Park in Gwynedd, Wales Arête Cirque RibbonLake
Topographic Map of Crib Goch Cirque Arête Ribbon Lake
Horn A high mountain peak that forms when the walls of three or more glacial cirques intersect. A pyramidal peak, or sometimes in its most extreme form called a glacial horn, is a mountaintop that has been modified by the action of ice during glaciation and frost weathering.
Mount Wilbur, Glacier National Park in Montana Glacial Horn RibbonLake Cirque
Topographic map of Mount Wilbur Ribbon Lake Glacial Horn Cirque U-shape Valley?
Moraines Glacial moraine at Borrowdale, Lake District, Cumbria Moraine : a French word that refers to any glacier-formed accumulation . Terminal moraine : an accumulation at the outermost edge of where a glacier or ice sheet existed. Recessional moraine: moraine located "behind" the outermost edge of a glacier, formed when the glacier lingers in one spot for a long time. Ground moraine: gently rolling hills and plains deposited by ice. Lateral moraine: ridges of till on the sides of a glacier. Medial moraine: a moraine formed when two glaciers merge (a tributary and trunk glacier) and their lateral moraines come together to form a single moraine. Push moraine: a moraine created by till that was a moraine deposited by an earlier glacier that once covered the area. Ablation moraine: a moraine formed from material that fell upon the glacier.
This ridge along the edge of a field is evidence that this area was covered by ice about 10,000 years ago. It was not constructed, but was left at the front of a melting glacier, as with melting glaciers in Canada or Norway today. As glaciers move, they scrape along the valley floor, eroding large amounts of rock material. They also transport frost-shattered boulders that fall from the valley sides and land on the glacier. When the glacier melts, this mixture of finely-ground rock, pebbles, and large boulders – moraine – is left as ridges both at the glacier “snout” (terminal moraine) and along the valley sides (lateral moraine).