Constructive/Destructive Processes copy1
deborah_isaac
Water Deposition
Sediment is carried by river
Glacial Deposition
• A volcano is an opening in the Earth's surface
or crust, which allows hot, molten rock, ash and
gases to escape from deep below the surface.
• Volcanic activity involving the extrusion of rock
tends to form mountains or features like
mountains over a period of time.
• Magma (inside)
• Lava (outside)
or crust, which allows hot, molten rock, ash and
gases to escape from deep below the surface.
• Volcanic activity involving the extrusion of rock
tends to form mountains or features like
mountains over a period of time.
• Magma (inside)
• Lava (outside)
Volcanoes
Volcanoes
• There are two main types of volcanoes: shield
and composite .
and composite .
• Shield volcanoes are usually found in the middle
of tectonic plates. (Islands like Hawaii are good
examples of this type of volcano).
of tectonic plates. (Islands like Hawaii are good
examples of this type of volcano).
• There's a hole in the middle of the plate and
magma moves out and piles on top of itself,
slowly building a mountain of rock. (Katmai)
magma moves out and piles on top of itself,
slowly building a mountain of rock. (Katmai)
Tectonic Plates
• Mountains can be
formed because of
moving tectonic
plates.
formed because of
moving tectonic
plates.
Faults
• Faults are cracks in the Earth’s crust.
• The surface of the Earth is made up of tectonic
plates that are floating on magma (molten rock).
• It is along these fault lines that earthquakes and
volcanoes occur.
• The surface of the Earth is made up of tectonic
plates that are floating on magma (molten rock).
• It is along these fault lines that earthquakes and
volcanoes occur.
Earthquakes
• An earthquake is a phenomenon that
results from the sudden release of stored
energy in the Earth’s crust.
results from the sudden release of stored
energy in the Earth’s crust.
• It is caused by a strain on the fault lines of
the Earth’s crust. When the energy of the
strain is released, similar to a rubber band
snapping, the earthquake occurs.
the Earth’s crust. When the energy of the
strain is released, similar to a rubber band
snapping, the earthquake occurs.
• At the Earth's surface, earthquakes cause a
shaking or displacement of the ground and
sometimes cause the ground to break apart
and change shape.
shaking or displacement of the ground and
sometimes cause the ground to break apart
and change shape.
Earthquake
Weathering and Erosion
• Weathering is the breakdown of the continents and the
land around you. The breaking down of these rocks and
land due to forces such as wind and water is weathering.
When it rains, rocks are washed down a mountain or
down a stream. Soils are washed away. The ocean
beats against a cliff and breaks it apart. If it is moved
elsewhere it is called erosion.
land around you. The breaking down of these rocks and
land due to forces such as wind and water is weathering.
When it rains, rocks are washed down a mountain or
down a stream. Soils are washed away. The ocean
beats against a cliff and breaks it apart. If it is moved
elsewhere it is called erosion.
Mechanical Weathering
• Mechanical weathering is the
process of breaking big rocks
into little ones. This process
usually happens near the surface
of the planet. Temperature also
affects the land. The cool nights
and hot days always cause
things to expand and contract.
That movement can cause rocks
to crack and break apart. Roots
and plants also push into the
rocks and break them apart.
They act like wedges and push
the rocks apart. Little animals
also help by burrowing and
digging through the ground.
process of breaking big rocks
into little ones. This process
usually happens near the surface
of the planet. Temperature also
affects the land. The cool nights
and hot days always cause
things to expand and contract.
That movement can cause rocks
to crack and break apart. Roots
and plants also push into the
rocks and break them apart.
They act like wedges and push
the rocks apart. Little animals
also help by burrowing and
digging through the ground.
Chemical Weathering
• Chemical weathering
includes the effect of
weathering on molecules
and atoms. As with all
chemistry, the greater the
surface area of an object,
the more chemical reactions
can take place. For these
chemical reactions to
happen in nature, moisture,
and heat must be present.
includes the effect of
weathering on molecules
and atoms. As with all
chemistry, the greater the
surface area of an object,
the more chemical reactions
can take place. For these
chemical reactions to
happen in nature, moisture,
and heat must be present.
Biological Weathering
(Impact of Organisms)
• Biological weathering
would include the effect
of animals and plants
on the landscape. This
is more than roots
digging in and wedging
rocks. Biological
weathering is the
actual molecular
breakdown of minerals.
would include the effect
of animals and plants
on the landscape. This
is more than roots
digging in and wedging
rocks. Biological
weathering is the
actual molecular
breakdown of minerals.
Earthquakes
• More than buildings collapse
when an earthquake hits. The
land itself is totally changed. You
can see scars across the
landscape. Those scars appear
when one block of land has
moved compared to another.
Roads often change their
placement. They either become
uneven or just crack. Streams
can also change course.
Sometimes rocks can fall and
block the stream. Other times,
the land is even lowered in
certain areas. When it's lower,
it's easier for the water to flow in
the new direction .
when an earthquake hits. The
land itself is totally changed. You
can see scars across the
landscape. Those scars appear
when one block of land has
moved compared to another.
Roads often change their
placement. They either become
uneven or just crack. Streams
can also change course.
Sometimes rocks can fall and
block the stream. Other times,
the land is even lowered in
certain areas. When it's lower,
it's easier for the water to flow in
the new direction .
Earthquakes
• San Andreas Fault line is 810 miles and
runs along California. It separates the
tectonic boundary of the Pacific and North
America boundary.
runs along California. It separates the
tectonic boundary of the Pacific and North
America boundary.
Seismic Waves
• Scientists study earthquakes so that they can
understand how they work and so that they can try to
predict future quakes.
• Earthquakes are recorded by instruments called
“seismographs”.
• A short wiggly line means a small earthquake and a
large one means a large earthquake.
understand how they work and so that they can try to
predict future quakes.
• Earthquakes are recorded by instruments called
“seismographs”.
• A short wiggly line means a small earthquake and a
large one means a large earthquake.
Flood Control Methods
• Dams control the water
flow in a stream or river.
flow in a stream or river.
• A levee is an
embankment designed to
prevent the flooding of a
river.
embankment designed to
prevent the flooding of a
river.
• Storm drains are for
carrying off rainfall
drained from paved
surfaces, roofs, etc.
carrying off rainfall
drained from paved
surfaces, roofs, etc.
Beach Reclamation
• Weather , waves and wind cause the
coastline to wash away.
• Keeping sand dunes intact helps to keep
the beaches from eroding .
coastline to wash away.
• Keeping sand dunes intact helps to keep
the beaches from eroding .
