Download Landforms

Physical
Processes:
Mrs. Walker
4th Grade
Earth’s Surface:
• The surface of the earth is made up of many
different landforms.
• A landform is a natural shape and type of
land on Earth’s surface.
Landforms:
• Mountains
• Hills
• Plateau
• Plains
• Valley
• River
• Peninsula
• Canyon
• Glacier
• Volcano
Guided Practice:
Landform Review
Complete
Land and Water
Formations
Worksheet.
Lets Think!!!
• Does Earth’s surface ever
change?
• What causes those
changes?
• Why? How? Examples?
Physical Processes:
• Earth’s surface is constantly
changing.
• Different natural events, such as
earthquakes and volcanoes, change
the size and shape of landforms.
• These events are known as physical
processes.
Example: Mt. Saint Helens (1980)
Before
After
Example: Earthquake/Tsunami in Japan
Before
After
Lets Review:
• Earth’s surface is made up of many
different types of landforms.
• Physical processes, such as volcanos,
earthquakes, flooding, and erosion shape
and reshape earth’s surface.
Preview:
• In our next lesson we will learn about a theory
that explains why earthquakes and volcanos
happen and how mountains are formed.
Plate Tectonics
Plate Tectonics
The theory
that Earth’s
plates float on
magma and
slowly shift
over time.
Plate
Definition:
A large sheet of rock that
makes up Earth’s outer crust.
Mountain
Definition: A natural rise of the earth with
steep sides.
Mountains are formed when plates collide
and the land buckles upwards.
Towel Demonstration:
How are mountains formed?
Earthquake
Definition:
Occur when two
of the earth’s
plates move
causing
vibrations, or
shaking to
occur.
Earth’s crust has many weak spots along
plate edges. When plates rub against
each other, Earth’s crust cracks and
chips under the pressure. These cracks
are called faults. When the crust moves
along faults, great amounts of energy are
released in the form of earthquakes.
Earthquakes cause dramatic changes to
the surface of the earth.
Bam, Iran
12/26/2003
Volcano
Definition:
An opening in the earth’s
crust from which lava
flows.
Plates move in different directions. In
some places, plates move apart and
magma leaks out through cracks in the
crust. In other places the plates push
against each other. This pressure forces
one plate to slide under the other.
Overtime, tremendous pressure and heat
build up. Molten rock gushes upward,
exploding from beneath the ground. This
is how volcanos are formed.
Plate Tectonics: Volcano Formation
Mt. St. Helens
5/18/1980
Plate Tectonics Video
Plate Tectonics
Mountains
Volcanos
Formed when 2
Formed when
plates collide and
plates collide and
one plate moves
the land buckles
under another causing
upward.
magma to flow
upward and
Plates
erupt onto
Shift
Earth’s
surface.
Formed when 2 plates move
and rub against each other
causing vibrations,
or shaking
Earthquakes
Weathering and Erosion
Weathering
Definition: The wearing away of a
surface through weather conditions,
such as wind, rain or ice.
Erosion
Definition: A process that breaks rocks
down into tiny pieces and moves them
to another location.
Erosion
• Wind, rain, and ice cause erosion
which slowly wear away Earth’s
landforms.
• Erosion helps create soil. (Tiny
fragments of rock mix with decay
mix with decayed animal and
plant material to form soil.)
• Over time, erosion can create new
landforms.
Erosion:
The Grand Canyon was formed by erosion.
What’s the Difference?
• Erosion involves running water,
blowing wind, or moving ice that
picks up and moves the particles to
another location.
• Weathering takes place as rocks
are broken down into smaller
pieces by the effects of weather.
These pieces do not move to a new
location, they simply break down,
but remain next to one another.
KWL Chart
Topic: Weathering and Erosion
What I Know
1. Weathering and
erosion cause Earth’s
surface to change.
2. Weathering breaks
down Earth’s surface
into smaller particles
but doesn’t move them.
3. Erosion breaks down
Earth’s surface into
smaller particles and
moves them to another
place.
What I Want to Know
1.
2.
3.
4.
How quickly does
weathering and
erosion happen?
What forces cause
weathering and
erosion to happen?
What happens to the
particles after they
have been broken
down.
How does weathering
and erosion affect
people?
What I Learned
Weathering and Erosion Video
KWL Chart
Topic: Weathering and Erosion
What I Know
1. Weathering and
erosion cause Earth’s
surface to change.
2. Weathering breaks
down Earth’s surface
into smaller particles
but doesn’t move them.
3. Erosion breaks down
Earth’s surface into
smaller particles and
moves them to another
place.
What I Want to Know
1.
2.
3.
4.
How quickly does
weathering and
erosion happen?
What forces cause
weathering and
erosion to happen?
What happens to the
particles after they
have been broken
down.
How does weathering
and erosion affect
people?
What I Learned
1. Most (but not all)
weathering and erosion
occur very slowly.
2. Water, ice, wind,
temperature, and gravity
are all forces that cause
weathering and erosion.
3. Broken down particles
can become soil or sand.
Also, new landforms can
be formed.
4. Can damage housing or
crops.
Flooding
Definition:
An overflow of
water onto land
that is normally
dry.
Flooding is
often caused by
heavy rains.
Flooding
• Overflowing rivers add nutrients to the surrounding
soil.
• If the Mississippi River were to flood, there would be an
increase in fertile soil in the MS River Valley.
Check for Understanding:
1. What creates new landforms?
a) Earthquakes
b) Volcanoes
c) Erosion
d) All of the Above
Check for Understanding:
2. Which of these does not cause
weathering?
a) sunshine
b)wind
c) rain
d)ice
Check for Understanding:
3. Which United States landform
was most likely caused by
erosion?
a) The Great Lakes
b)The Mississippi River
c) The Rocky Mountains
d)The Grand Canyon
Check for Understanding:
4. Which physical process most
likely formed the Great
Smoky Mountains?
a) Flooding rivers
b)Erupting volcanoes
c) Plate tectonics
d)Wind erosion
Check for Understanding:
5. Which physical process most
likely causes a river to overflow,
adding nutrients to the local soil?
a) Heavy rains
b)Volcanic eruptions
c) Strong Winds
d)Melting Snow
Check for Understanding:
6. Which physical process
most likely shaped the
feature shown?
a) Plate tectonics
b) Volcanic eruptions
c) Water erosion
d) Coastal flooding
Check for Understanding:
7. Which physical process
most likely created the
mountain range shown
on the map?
a) erosion
b) flooding
c) plate tectonics
d) volcanic eruptions