Glacial Landforms and the Ice Age

1
Glacial Landforms and the Ice Age

• Glaciers
• Alpine Glaciers
• Ice Sheets
• The Ice Age
• Landforms Made by Ice Sheets

2
Alpine Glaciers Vs Ice Sheets

• Glacial Ice forms under pressure when accumulate
  when snowfall exceeds snow loss
• 1. Alpine Glaciers form in high mountains,
• 2. Ice sheets form on continental interiors at
  high
  latitudes

(ablation)
Perito Moreno Glacier - Argentina
Ellesmere Island, Canada
3
Glaciers

• Thick ice mass becomes plastic, flow starts, and
  the ice mass is now an active glacier
• Depositions, abrasion and plucking

4
Glacial Landforms and the Ice Age

• Glaciers
• Alpine Glaciers
• Ice Sheets
• Landforms Made by Ice Sheets
• The Ice Age

5
Alpine Glaciers

• Cirque
• Normal cm-m/day
• Surging up to 60m/day

6
Alpine glacier produced landforms
Smooth, Weathered hills, V shaped stream
7
Alpine Glacier produced landforms
After a thousand years of glaciation
8
(No Transcript)
9
Alpine glacier produced landforms
Glacier ice recedes, Troughs are exposed
10
Tierra del Fuego, Chile/Argentina
11
(No Transcript)
12
Moraines are comprised of highly unsorted
material (various sizes), as a soil-type, this is
called till
North Cal
North Cal
13
(No Transcript)
14
Alpine glacier produced landforms
Streams and Fiords
15
(No Transcript)
16
(No Transcript)
17
Glacial Landforms and the Ice Age

• Glaciers
• Alpine Glaciers
• Ice Sheets
• Landforms Made by Ice Sheets
• The Ice Age

18
Ice Sheets (and shelves)

• Huge plates of ice thousands of meters thick
  resting on land masses (and the attached floating
  ice)

(about 5 million mi2)
Occupies 7/8 of Greenland
19
(No Transcript)
20
Sea ice Vs ice bergs

• Icebergs bodies of land ice that have broken
  free (may be hundreds of meters thick).
• Sea ice direct freezing of ocean water (lt 5m
  thick) pack ice completely covers the sea
  surface

21
(No Transcript)
22
Glacial Landforms and the Ice Age

• Glaciers
• Alpine Glaciers
• Ice Sheets
• The Ice Age
• Landforms Made by Ice Sheets

23
Ice Age!

• Cycles of glaciation, deglaciation, and
  interglaciation!
• ? Causes ?
• ? Change in the position of the continents
• ? Increased volcanism
• ? Decrease in the Suns output of energy

Milankovitch curve cycles of the ice age
24
Ice Age!

• Maximum ice advance of the Wisconsinan
  Glaciation was reached about 18,000 years ago

25
Glacial Landforms and the Ice Age

• Glaciers
• Alpine Glaciers
• Ice Sheets
• The Ice Age
• Landforms Made by Ice Sheets

26
Landforms Made by Ice Sheets

• Highly effective eroding agents Slow moving ice
  scraps and grounds away bedrock, leaving behind
  smoothly rounded rock masses

27
Glacial Abrasion
28
Landforms Made by Ice Sheeets

• Glacial drifts all types of rock debris
  deposited by glaciers
• Stratified drift includes sediment laid by
  running water
• Till sediment deposited directly by ice

29
Landforms Made by Ice Sheets
30
(No Transcript)
31
(No Transcript)
32
(No Transcript)
33
(No Transcript)
34
So How were Michigans cool great lakes formed?

• http//www.on.ec.gc.ca/greatlakeskids/GreatLakesMo
  vie5.html

35
Glacial Landforms and the Ice Age

• Glaciers
• Alpine Glaciers
• Ice Sheets
• The Ice Age
• Landforms Made by Ice Sheets