Transcript 17. Erosion

TYPES OF EROSION
© Copyright 2004 - 2005. M. J. Krech. All rights reserved.
WHAT IS
EROSION
?
Erosion is the movement of weathered rocks
and soil particles from one place to another.
THERE ARE FIVE AGENTS
OF EROSION.
•
•
•
•
•
GRAVITY
GLACIERS
WIND
WATER
WAVES
GRAVITY
EROSION CAUSED BY
GRAVITY IS CALLED
MASS
WASTING.
RAPID MASS WASTING
One type of rapid
mass wasting is
LANDSLIDE
which is the tumbling
of dry soil and rocks
downhill
RAPID MASS WASTING
Another type is
MUDFLOW
where rain mixes with
the soil to form mud
which moves
downhill
RAPID MASS WASTING
Another type is
SLUMP
where a huge
block of rock
slides rapidly
down a hillside.
SLOW MASS WASTING
One type of slow mass
wasting is
EARTHFLOW
where a mass of soil and
plant life begin to slowly
move downhill after a
heavy rain.
SLOW MASS WASTING
Another type is
CREEP
where soil particles
move slowly downhill.
This is the slowest.
GLACIERS
A
GLACIER
is a large mass of
moving ice and
snow.
GLACIERS
Glaciers move
rocks by
PLUCKING
where ice freezes
around a rock and
moves it along as the
glacier moves.
GLACIERS
Glaciers also move rocks
by
ABRASION
where rocks are loosened
and moved by the glacier,
causing scratches on the
bedrock.
WIND
Wind moves soil by
DEFLATION
where wind removes
loose material from
the land.
Here smaller sand grains are blown
away from around larger rocks.
WATER
Running water is the
major cause of
erosion.
Water picks up and
carries loose particles
of soil as it moves
downhill.
WATER
Water starts out
in tiny grooves
called
RILLS
WATER
Rills become wider
and deeper,
called
GULLIES
WATER
Gullies turn into
STREAMS
which turn into
RIVERS.
WAVES
Waves carry off small
rocks and sand from
the beach.
EROSION
A.
What is the
agent of
erosion in this
picture?
EROSION
B.
What is the
agent of erosion
in this picture?
EROSION
C.
What is the
agent of
erosion in
this picture?
EROSION
D.
What is the
agent of erosion
in this picture?
EROSION
E.
What is the
agent of
erosion in
this picture?
THE END
F.
BONUS:
List at least
three types of
erosion in
this picture
and how you
know.
© Copyright 2004 - 2005. M. J. Krech. All rights reserved.