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Explore the fascinating world of glacial erosion in this comprehensive lecture. Learn about the slow processes of mountains forming and wearing down over millions of years. Discover how streams erode, transport, and deposit grains, while glaciers have the power to reshape landscapes on a larger scale. Explore the effects of ice ages, water, and ice flows, and the different scales of glaciation. Dive into topics such as alpine and continental glaciation, cirques, horn, aretes, cols, and more, comparing the unique features of glacial and stream erosion. View stunning photos showcasing the U-shaped valleys, hanging waterfalls, and other remarkable formations carved by glaciers. Join us in unraveling the mysteries of glacial activity and its impact on the Earth's surface.
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Boulder, boulder, big and round,Tell me something, real profound. - Johnny Hart (B.C.)Glacial erosion Lecture 16 Webpage for course (daytime) Webpage for course (nighttime)
Lab midterm scores 65 4 64 2 63 62 2 61 3 60 4 59 58 4 57 55 2 54 2 53 52 49 47 45 40 39 31 26 2 17 3 11 2
http://www.learner.org/courses/essential/earthspace/images/show6_ice_age.jpg&imgrefurlhttp://www.learner.org/courses/essential/earthspace/images/show6_ice_age.jpg&imgrefurl
Geologic processes are usually slow Mountains come up, worn down Over millions of years Streams take a long time to Erode transport and deposit their grains The grains transported are small
Glaciers Can erode larger portions of mtns Transport and deposit the material Over 10,000s years Grains can be the size of trucks
Water Ice Flows slowly – bulldozer effect High viscosity – flows around obstructions
Two general kinds (scales) of glaciation Alpine Continental
Snow Accumulates in mtns colder weather – advances warmer weather - retreats Flows to lowlands
In mountains – erosion on large scale Glacial quarrying (plucking) Abrasion Avalanching
Cirques http://www.goldengatephoto.com/westus/greatbasin.html&usg
In valleys – transportation on large scale Glacial vs. Stream U-shape Less sinuous HUGE Hanging waterfalls