glaciers section 9.4. glaciers are any large mass of ice that moves over land continental glaciers -...
TRANSCRIPT
Glaciers are any large mass of ice that moves over land
• Continental Glaciers
- cover much of a continent or large
island (10% of Earth’s land today
- Antarctica, Greenland)
Continental Glaciers
- spread out in all directions
- during the last ice age, glaciers covered 1/3 of Earth and retreated 10,000 years ago
Valley Glaciers
• Long narrow glacier that forms when snow and ice build up in mountains
• move down valleys that were cut by rivers
Valley Glaciers
• moves down hill when snow reaches 30-40m
• can move a few centimeters to a few meters per day.
• A surging glacier can move up to
6km per year
Valley Glaciers
Glacial Deposit
Till – jumble of different sized rock deposited when a glacier melts
Moraine – ridge of till deposited at the end
of a glacier
Kettle – a depression in till that is left when a chunk of ice is left by a retreating glacier. Often filled with water.
Other land forms
• Fiord
• Horn
• Cirque
• Arete
• Drumlin