1. Glaciation

2. Shaping of the Earth There are many processes that shape the earth
Some are natural (those associated with weather)
The Natural processes are usually referred to as “Erosion”
The movement of the earth’s surface from one location to another
Some and human (man made interference)
-There are 3 Major NATURAL processes that shape the Earth and its surface

3. Processes that erode:
Water

4. Processes that erode:
Water
Wind

5. Processes that erode:
Water
Wind
Ice

6. The Glacier by Arthur Lismer
Glaciation
The Glacier by Arthur Lismer

7. Glaciation is a Glacial Period or Ice Age
The earth has experienced several ice ages
2 billion years ago
600 million years ago
250 million years ago (Pangea)
1 to 2 million years ago
Most recent was 100,000 years ago, ending 6,000 years ago
Ice sheets covered almost all of Canada, up to 4 km thick
Due to cold climate, enormous amounts of water were frozen in ice sheets causing the water level of oceans to fall.
Ice sheet is a mass of ice larger than 50,000 km²

8. What is a glacier?
A glacier is a large, slow moving piece of ice, formed from compacted layers of snow, that slowly deforms (melts, freezes) and flows in response to gravity.

9. Glacier Formation Earth’s climate is cool
Snow that falls does not completely melt
Over many years, the snow gets deeper and becomes hundreds and thousands of metres thick.
Tremendous weight of snow on top causes the bottom layers to turn to ice that is very dense.
This pressure along with gravity causes glaciers to move…in different ways

10. Two types of glaciers:
Alpine Glaciers
Continental Glaciers

11. Alpine Glaciers Are found in mountain regions
Move under the force of gravity
Sharpen the upper portions of he mountain
Scrape away the valley walls to produce U-shaped valleys
Moraine is formed from the debris
Oak Ridges Moraine
Very fertile for agriculture and thriving wildlife

12. The Columbia Icefield

13. The Columbia Icefield People for scale

14. The Columbia Icefield Deposition of scraped material

15. The Columbia Icefield
Space that it probably occupied and melted down to what you see now

16. Continental Glaciers Cover large areas of land Move under own weight
Spread outward from center or zone of accumulation
Edge or margin of glacier can advance, retreat or stay in one place.
Smoothes the landscape by eroding high points and filling in lower areas

17. Continental Glaciers continued
This erosion can expand existing river valleys, making them deeper and wider
U-shaped Valleys
Can also make lakes deeper and wider
The Great Lakes were formed this way
Once covered and shaped the Canadian Shield but today they only exist in Greenland and Antarctica.

18. Questions How are glaciers formed? How do glaciers move?
What are the main differences between an Alpine and Continental Glacier?
Where can we find glaciers today?
Which areas of Canada were shaped by Glaciation?
How were the Great Lakes formed?