EAS100 Lecture Notes - Lecture 22: Aretes, Cryosphere

• School: University of Alberta
• Department: Earth and Atmospheric Sciences
• Course: EAS100
• Professor: Jeffrey Kavanaugh

Document Summary

Top 50m of glacier is brittle - does not deform readily. Crevasses form in top layer as glacier bends over topography or is streched quickly. Ice is ablated by falling from front of glacier. Portions of bed at melting point, with ice higher up below freezing. Hanging valleys (tributary valley well above valley floor) Horns (pointed pyramidal peaks, (intersections of 3 bowls)) Terminal morains (form at the lowest extent of the glacier) lateral moraines (form along the sides of the glacier) Drumlins (icesheets, form oblong hills, related to ice flow or water. Eskers (wet temperate glaciers leave ridges of well sorted sand and flow) gravel from basal rivers) Kames (wet temperate glaciers leave piles of gravel and sand upon melting) As ocean water freezes, the ice excludes the salt, making the surrounding water more saline, and it sinks into the deep ocean currents.