1.4 Understand how
moving ice acts as an
agent of erosion and
deposition. (Chap. 2)
There are two types of
glaciation.
• Alpine Glaciation
• Continental Glaciation
Distinguish between the
terms alpine glaciation and
continental glaciation.
(P.32)
Alpine Glaciation
• Alpine glaciers form high in mountain
valleys; above the snow-line
C
D
E
B
A
Alpine Glaciation
Continental Glaciation
• Continental glaciers cover parts of
continental land masses; ex Greenland
Distinguish between the terms alpine
glaciation and continental glaciation.
(P.32)
Similarities
Differences
• Both move and
cause erosion
• Both change the
landscape
• Both developed
in constantly
cold < 0 0C
• Location
• Alpine =
mountain
• Continental =
earth poles
• Size
• Alpine = smaller
• Continental =
larger
Define the terms outwash plain,
terminal moraine, erratics, drumlins &
eskers. (P. 33 Q.12)
• These
features are
associated
with
continental
glaciation.
• See picture
p. 34
Outwash plain
Outwash plain
• Similar to a
river delta
• Melt water
flowing from the
glacier deposits
silt
• Deposited in
layers
• Small particles
carried further
away
• Larger particles
drop closer to
the glacier
Outwash Plain
Continental…Outwash plain
Outwash
Plain
Continental…Outwash plain
Continental…Outwash plain
Terminal moraine
• Heap or ridge
of bulldozed
gravel that
marks the end
of the forward
motion of a
glacier
• As glacier
retreats it
deposits
debris/gravel
• P. 34
Continental…Terminal Moraine
Terminal
Moraine
Outwash
Plain
Continental…Terminal Moraine
Erratics
• Large boulders that were transported
long distances and dropped
• They now sit in a region and look very
much out-of-place.
• P. 34
Erratic
Erratic
Continental…Erratic
Terminal
Moraine
Outwash
Plain
Erratic
Drumlins
p. 34 • Egg shaped hill
• Formed under
glaciers
• Sloped or Pointy
end points in
direction of ice
flow
Drumlins
p. 34
• Formation
• Ice melts under glacier
• Deposits of gravel made
• Glacier moves forward
• Deposits are bull-dozed along and
catches up in rough areas
forming piles or drumlins.
Drumlin
What direction did the glacier move?
Continental…Drumlin
Drumlins
Terminal
Moraine
Outwash
Plain
Erratic
Esker p. 34
• Long deposits of eroded glacial
material
• Formed by sub-glacial streams that
deposit material like all rivers.
• Highways of the North!!
Esker
Esker
Continental…Esker
Drumlins
Terminal
Moraine
Esker
Outwash
Plain
Erratic
Examine evidence for the direction of
movement of glaciers. (P. 34 question #
13)
1. Sloped end of
drumlin
2. Location of
terminal
moraine
• What is
direction of
glacier
movement in
this picture?
Continental…Outwash Plain
Define the terms cirque, arête, hanging
valley, lateral moraine, and terminal
moraine.
(P. 36)
• These features
are associated
with alpine
glaciers
Alpine glaciers
• Alpine
glaciers are
like very slow
moving rivers
of ice flowing
down high
mountain
valleys.
Cirque (p. 36)
• a circular hollow cut into bedrock during
glaciation
• Side and back walls are steep but front wall
opens downward
Cirque - How formed?
• Alpine glacier
freezes onto
mountain
valley and as
is proceeds it
plucks rock
from the
mountain top
leaving the
cirque shape.
C
D
E
Cirque
B
A
Cirque
Arête p. 36
• Steep,
jagged,
narrow,
knife edged
ridge
between two
cirques or
glacier
valleys.
Arete C
D
E
Cirque
B
A
Arête
Truncated Spur
• Blunt-ended ridge of rock jutting
from the side of a glacial
trough, or valley
Arete C
Truncated spurs
A
D
E
Cirque
B
Horn or Pyramidal Peak
• is a mountaintop (peak) that has
been modified by the action of
ice during glaciation.
Arete C
Truncated spurs
A
Horn
D
E
Cirque
B
Horn
Hanging Valley
Most noticeable once glacier
has melted!
• A high level
tributary valley
from which the
ground falls
sharply to the
level of the
lower, main
valley.
• The depth of the
lower valley is
due to more
severe
glaciation.
Hanging Valley
Hanging
Valley
Hanging Valley in
Newfoundland
• Hanging Valley
in Gros Morne
National park .
• Trout River pond
Lateral Moraine
• Moraine means 'rock waste'.It is also
known as glacial till
• Lateral Moraine is the land-form
deposited at the side of a glacier
• Debris/waste rock drops off the side
of the mountain as the glacier moves
forming a ridge of debris at the
outer-sides of the glacier.
Lateral Moraine
•Lateral Moraines
Kaskawulsh Glacier
St. Elias Mtns - Arctic
Terminal Moraine
• deposits that mark the farthest
extent of the glacier
• Good indicator of the direction
or movement of the glacier as
well.
Alpine Glaciation
• Terminal Moraine
Medial Moraine
• This is a ridge of rock waste
found along the middle of the
floor of a u - shaped valley.
• It occurs when two glaciers
meet, two lateral moraines
unite to form a medial moraine.
Medial Moraine
•Medial Moraine
Medial Moraine
• Medial Moraine
Alpine Glaciation
Kaskawulsh Glacier
St. Elias Mtns - Arctic
Describe how fiords are
formed. (P.37)
1. Alpine Glaciers
erode troughs &
valleys in the
mountain
2. Glacier valley reaches
the coast.
3. Glacier melts and sea
water floods the valley
Fiord
• A glacially eroded or modified
U-shaped valley that extends
below sea level and connects to
the ocean. Filled with
seawater…
Gross Morne - Fiord
Fiord in Norway
• Norway is well
known for its
abundant fiords
Continental Glacier