1. Glaciers
Section 9.4

2. 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)

3. Continental Glaciers spread out in all directions
during the last ice age, glaciers covered 1/3 of Earth and retreated 10,000 years ago

4. Continental Glaciers

5. Valley Glaciers
Long narrow glacier that forms when snow and ice build up in mountains
move down valleys that were cut by rivers

6. Valley Glaciers can be many kilometers long
form in areas where more snow falls than melts

7. 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

8. Valley Glaciers

9. Plucking- weight of a glacier breaks
Glacial Erosion
Plucking- weight of a glacier breaks
underlying rock and the pieces
stick to bottom

10. Abrasion- pieces of rock on the bottom
of a glacier gouge and scratch
the bedrock

11. Plucking and Abrasion

12. Glacial Deposit Till – jumble of different sized rock deposited
when a glacier melts
Moraine – ridge of till
deposited at the end
of a glacier

13. Terminal Moraine – ridge formed at the
furthest point reached by a glacier
(Long Island)

14. Kettle – a depression in till that is left
when a chunk of ice is left by a
retreating glacier. Often filled with
water.

15. Other land forms
Fiord
Horn
Cirque
Arete
Drumlin