Download presentation
Presentation is loading. Please wait.
Published byAlexandra Cannon Modified over 9 years ago
1
Day #2-Processes That Shape Ocean Basins and Drainage Section 2.3
2
Review What is the lithosphere? Core (rock) and upper mantle (clay)
3
The Plan Discuss glaciers, video clips, newspaper article, and activity. I can describe glacial features. http://uncoveringgeology.com/geoparks/
4
Glaciers Glaciers are large moving bodies of ice. Continental glaciers (or icecaps) are glaciers that cover vast areas of land. Antarctica is covered by a continental glacier that is about 1 and 1/3 times the area of Alberta!
5
Where Glaciers are Found They are located wherever snow can collect and survive. Most are fund in the polar regions. http://pbs.panda- prod.cdn.s3.amazonaws.com/media/assets/wgbh/ess05/ess05_int_glacie rs/01_Where.htm
6
How Glaciers Form Snow in an area does not all melt in summer. Each winter, more snow is added. The weight of all the snow creates pressure = turns the lower parts of the snow into ice. http://pbs.panda- prod.cdn.s3.amazonaws.com/media/assets/wgbh/ess05/ess05_int_ glaciers/01_Form.htm
7
Valley Glaciers Valley glaciers are glaciers that form high up in mountain ranges. Snow and ice build up and then begin to move. These glaciers flow down between the mountains. These glaciers collect pieces of rock, which drag on the surface and determine the form of the land. http://becuo.com/valley-glacier
8
The Athabasca Glacier
9
Glacial Movement Glaciers move by internal changes due to pressure or stress and slide at the base. The ice in the middle of a glacier flows faster than the ice along the sides of a glacier. https://www.asf.alaska.edu/blog/how-do-glaciers-move/
10
Glacial Movement The movement of glaciers depends on the climate. Cooler = little melting, snow builds up. The glacier is said to be advancing (moves forward). Warmer = more melting, snow melts. The glacier is said to be retreating (moves backward). Glaciers always flow downhill.
11
Western Canada Could Lose 70% of its Glaciers by Century’s End! http://www.edmontonjournal.com/news/edmonton/Western+Canada+could+lose+cent+glaciers+century+study/10949122/story.html
12
Ice Ages Today we have few continental and valley glaciers that cover the Earth. In the past, large areas of the Earth were covered with glaciers. This was the time of the Ice Ages. The Ice Ages shaped most of Canada’s geography. http://io9.com/everything-you-need-to-know-about-the-five-ice- ages-of-471281603
13
Glacial Features 1. Moraines 2. Eskers 3. Drumlins 4. Kettle lakes As glaciers advance and retreat, they leave many structures:
14
Moraines Moraines form from rocks and sediment carried down and deposited by a glacier. Builds up along the sides and at the end of a glacier. As the edges of the glacier melt, large deposits form. http://www.landforms.eu/cairngorms/moraine.htm
15
Eskers Eskers are long ridges of gravel and other sediment, deposited by melt water from a retreating glacier or ice sheet. Typically in the pattern of a winding river. http://basementgeographer.com/eskers-rivers-of-rock/
16
Drumlins Drumlins are small hills with a distinctive teardrop shape. They form when a glacier moves over moraines that had formed earlier. The tip of the drumlin points in the direction that the glacier was moving.
17
Kettle Lakes Kettle lakes are lakes formed when large chunks of ice left behind by the glacier melted away. The action of glaciers make depressions in the land.
19
How Glaciers Shape the Land …and after a glacierDuring
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.