1.6 Understand how moving ice acts as an agent of erosion and

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1.4 Understand how
moving ice acts as an
agent of erosion and
deposition. (Chap. 2)
There are two types of
glaciation.
Continental Glaciation
Alpine Glaciation
Distinguish between the
terms alpine glaciation and
continental glaciation.
(P.32)
Continental Glaciation
• Continental glaciers cover parts of
continental land masses; ex Greenland
Alpine Glaciation
• Alpine glaciers form high in mountain
valleys; above the snow-line
C
D
E
B
A
Alpine Glaciation
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 Glacier –
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

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