Inside the Earth

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Inside the Earth
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Name ________________________________________________________________________
Scientists divide the earth into five distinct layers. Identify and list the ways these
layers are different and similar.
Mantle: The mantle is actually divided into three
layers. All three layers are so hot that they are
permanently molten. Magma usually forms in the
upper layer of the mantle from rocks rising into it
from the lower two layers. In the upper layer,
these rocks melt and burst through the
surface of the earth’s crust as lava.
Outer Core: Scientists
believe that the outer core is
composed mainly of iron and
nickel and is so hot that it is
probably always molten.
Crust: The surface of the
earth is actually composed
of two different types—
oceanic and continental.
Oceanic crust is quite thick,
at 4 miles (6 kilometers) in
depth, and young. The rocks
in oceanic crust are often no
more than 200 million years
old. Continental crust can
range from 16 miles (25 kilometers) to 56 miles (90 kilometers) in depth. Rocks
have been found in continental crust that are at least
3.8 billion years old.
Inner Core: Scientists believe that the inner
core is a solid ball of iron and nickel.
Temperatures
in othe inner core may reach as high
o
as 6,700 F (3,700 C). However, the pressures are
so high that this part of the earth remains solid
rather than molten (melted).
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Lithosphere: The lithosphere is
actually composed of all the earth’s
crust and a little bit of its upper
mantle. It extends 60 miles (100
km) below the surface of the earth.
INSIDE THE EARTH
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Copyright 2007 The American National Red Cross
Venn Diagram
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Name ________________________________________________________________________
Scientists often build models to show complex information that cannot be explained
very easily in words. Follow the steps below to consider and then show how the earth
and a layer cake are similar and different.
Directions:
1. What are some words you can use to describe the earth? Write them in the earth
circle of the Venn diagram below.
2. What are some words you can use to describe layer cake? Write them in the layer
cake circle of the Venn diagram below.
3. What are some words you can use to describe both the earth and the layer cake?
Put words that name shared characteristics in the overlapping section of the Venn
diagram.
Earth
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Layer Cake
VENN DIAGRAM
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Copyright 2007 The American National Red Cross
Venn Diagram
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Earth Layer Cake
You have learned that the earth is made up of several layers and ingredients.
Now it is your turn to become an “earth chef” and make an “earth layer cake.”
Directions:
1. Build your “earth layer cake” using different materials for each layer.
2. Build your cake to scale as closely as possible. That is, use thick materials
like the cake to show thick layers and thin materials like the icing or decorations to show thin layers.
3. Your layers must include—
• Lithosphere
• Crust
• Outer core
• Inner core
• Mantle
4. Use toothpicks and paper to label each layer.
Materials for the “earth layer cake”:
• Your completed Venn diagram
• Slices of cake
• 2 colors of icing
• Variety of candy and nut decorations
• Utensil to spread icing
• Toothpicks and a sheet of paper
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VENN DIAGRAM
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Graphing the Depth
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Name ________________________________________________________________________
Directions: The layers of the earth vary greatly in thickness. Create a bar graph to illustrate
these differences. Use the graph to answer the questions on the next page.
Thickness in
Kilometers
Layer
Crust
Lithosphere
Mantle
Outer core
Inner core
Thickness in Km (miles)
40 (25)
100 (62)
2,900 (1,802)
2,000 (1,243)
1,400 (870)
3000
2500
2000
1500
1000
500
0
Crust
Lithosphere
Mantle
Outer
core
Inner
core
Adapted from Earthquakes: A Teacher’s Package for K–6 developed by the National Science Teachers
Association with the support of the Federal Emergency Management Agency; revised April 1999.
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GRAPHING THE DEPTHS
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Graphing the Depth
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Now, answer the following questions:
1. Which layer of the earth is the thickest?
__________________________________________
2. Which layer of the earth is the thinnest?
__________________________________________
3. What is the total thickness of all the earth’s layers?
_________________________________________
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GRAPHING THE DEPTHS
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Facts About Pangaea
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Name ________________________________________________________________________
In 1912, a German scientist named Alfred Wegener had the idea that the
continents once formed a single huge landmass, which he called Pangaea. This
word means “all earth.” He suggested that Pangaea broke into pieces. We call
these pieces plates. The theory Wegener suggested to explain the drifting plates is
called the theory of plate tectonics and is sometimes referred to as continental
drift.
By 1929, Alfred Wegener’s ideas were all but dismissed. But, Arthur Holmes elaborated on one of Wegener’s hypotheses: thermal convection and the earth’s mantle.
Thermal convection states that, as a substance is heated, its density decreases and
it rises. Once it cools, its density increases and it falls. This continuing process
causes a current. Within the magma in the upper level of the mantle, this powerful
current can cause plates to break and continents to move in opposite directions,
floating on the convection currents.
More than 30 years later, in the early 1960s, other scientists began looking into
Holmes’s ideas to provide further illustration of Wegener’s theory of plate
tectonics. Harry Hess and Robert Dietz believed that the Mid-Atlantic Ridge
marked one place where Pangaea began to break apart. Their theories are that—
• Along the Mid-Atlantic Ridge, the ocean floor was ripped in two and
continuously pulled apart lengthwise as the newly created, drifting plates
floated apart.
• The rip formed a weak area in the crust.
• New magma rose and erupted through the weak crust along the
spreading ridge and formed new oceanic crust.
• The new oceanic crust continuously spread away from the ridges as the
new plates continued to separate.
• This process, called seafloor spreading, began many millions of years ago
and continues to this day. Along the Mid-Atlantic Ridge, the erupting lava
and drifting plates produced a huge basin that eventually filled with water to
become the Atlantic Ocean.
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FACTS ABOUT PANGAEA
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Facts About Pangaea
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Evidence for the Plate Tectonics Theory:
1. Here is the supercontinent of Pangaea, as it
began to break up about 225 million years
ago. Look at the image as if it were a puzzle
that you could take apart to form today’s
continents. Use a world map to decide which
piece you think represents which continent.
This suggests that the continents were, in
fact, once joined into one huge landmass,
torn away from each other by the force of the
convection currents in the mantle of the
earth.
2. A second piece of evidence supporting the idea of drifting continents is the close
match between fossils of Glossopteris (a genus of plants) and fossils of Mesosaurus
(a genus of reptiles) found on the eastern tip of Africa and those found on the corresponding part of South America.
3. The geological structures of the rocks in southwest Africa and southeast Brazil are
identical in their makeup and age. If Pangaea existed, these rocks would have been
part of one landmass. Rock formations of similar makeup and age are found in
Europe’s Caledonian Mountains and in the Appalachian Mountains in the southeast
United States.
4. The San Andreas Fault in California forms a section of the boundary between the
North American Plate on the east and the Pacific Plate on the west. The western
edge of California below San Francisco is actually on the Pacific Plate and has been
moving northward with respect to the rest of the continent. Geologists have found
sections of specific rock formations on opposite sides of the fault separated by
hundreds of kilometers. Streams that cross the fault have been offset by earthquakes, and even fences and buildings are pulling apart, creating additional
evidence of the Pacific Plate’s movement.
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FACTS ABOUT PANGAEA
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Pangaea Puzzle
Page 1 of 3
Name ________________________________________________________________________
Scientists theorize that over 225 million years ago, the landmass of the earth
looked like one supercontinent, Pangaea, meaning “all earth.” Over the eons, the
forces of plate tectonics broke up, moved and changed the single continent into
the continents we know today.
Directions: Use a world map and your imagination to cut and separate Pangaea
into today’s world. Name the landmasses.
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PANGAEA PUZZLE
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Pangaea Puzzle
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PANGAEA PUZZLE
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Pangaea Puzzle
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Puzzle Pieces
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PANGAEA PUZZLE
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Chocolate Crust
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Name ________________________________________________________________________
Directions: The experiments below will help you formulate a theory about the
effects of moving plates on the surface of the earth. Follow the steps to perform
each of the three experiments to determine what might happen when pieces of
the earth’s crust collide.
You have been given—
3 dense chocolate bars
3 less-dense chocolate bars
waxed paper
The dense chocolate bars represent continental
crust, and the less-dense chocolate bars represent
oceanic crust. You will work on a surface of waxed
paper.
After each experiment, discuss your observations
within your team and then briefly summarize a
theory to explain what happened on the lines
provided. Appoint a member of your team to describe your observations and
defend your explanatory theories to the class as a whole.
Experiment 1
1. Place one dense chocolate bar and one less-dense chocolate bar touching,
end to end, on the waxed paper.
2. Then, push the bars together with a gentle, slow and steady pressure.
3. What happens to each of the bars at the point of contact? On contact?
During contact? What is your theory to explain your observations?
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CHOCOLATE CRUST
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Chocolate Crust
Page 2 of 2
_________________________________________________________________________
_________________________________________________________________________
________________________________________________________________________
Experiment 2
1. Place one dense chocolate bar and a second dense chocolate bar touching, end
to end, on the waxed paper.
2. Then, push the bars together with a gentle, slow and steady pressure.
3. What happens to each of the bars at the point of contact? On contact?
During contact? What is your theory to explain your observations?
_________________________________________________________________________
_________________________________________________________________________
_________________________________________________________________________
Experiment 3
1. Place one less-dense chocolate bar and a second less-dense
chocolate bar touching, end to end, on the waxed paper.
2. Then, push the bars together with a gentle, slow and steady pressure.
3. What happens to each of the bars at the point of contact? On
contact? During contact? What is your theory to explain your
observations?
_________________________________________________________________________
_________________________________________________________________________
________________________________________________________________________
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CHOCOLATE CRUST
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EPICENTERS AROUND THE WORLD
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Directions: This is a map of the epicenters of earthquakes that have occurred around the world. Compare
what you see with your ideas of where most earthquakes occur.
Name ________________________________________________________________________
Page 1 of 1
Epicenters Around the World
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MAP OF THE EARTH’S PLATES
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Directions: This is a map of the earth’s 12 major plates. Many scientists identify even smaller plate boundaries,
dividing the earth into 20 plates. Compare these plate boundaries with the earthquake epicenters found on Epicenters
Around the World. Discuss how this information supports plate tectonics and the continuous motion of the earth.
Name ________________________________________________________________________
Page 1 of 1
Map of the Earth’s Plates
Map of Plate Movements
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Name ________________________________________________________________________
Directions: The earth’s plates are constantly moving because of the convection currents
within the magma. The movement is very slow, about 1 to 2 inches (2.5 to 5 centimeters)
per year, or about as fast as your fingernails grow.
The arrows on the plates shown on this map illustrate the direction in which each plate
moves. Plates may converge (come together), diverge (pull away from each other) or
move laterally (side to side).
Create a color code to identify the types of plate (oceanic or continental) and the type of
boundary movement represented by the arrows. Redraw these arrows, using your color
code, on Map of the Earth’s Plates to identify movement and plates by name and discuss
the effects on the earth’s crust.
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MAP OF PLATE MOVEMENTS
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Forming Faults
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Name ________________________________________________________________________
Faults are places in the earth where the rocks are broken and the rocks on
one side have moved in some direction (up, down or sideways) relative to
the rocks on the other side. The boundaries between plates are faults, and
there are other areas in the earth’s crust that have faults as well. These
faults, or cracks, are formed because of the tremendous pressure created
by the movement of the crust on top of the mantle.
Earth’s plates are so big that they move a little bit at a time, usually only a
section at a time. Even these little movements can release large amounts
of energy. Some plates have fracture zones, areas of many faults fairly
close to the edge of the plate. Some plates have weak
areas with faults far from the boundary.
There are three basic kinds of faults:
• Strike-slip fault (sideways movement): The
fault is vertical or nearly vertical. One side of
the fault moves sideways past the other. This
movement is also described as lateral or
transform.
• Normal fault (down movement): The fault
plane is angled, and one side moves down and
away from the other side.
• Thrust fault (up movement): The fault plane is
angled, and one side slides up over the other.
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FORMING FAULTS
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Forming Faults
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Materials:
• Modeling clay, 3 colors
• Rolling pin
• Ruler
Directions:
Use the clay and a rolling pin to create blocks of rock or sections of the earth’s
crust. Use three colors of clay to show layers of different types of rock. Use a
ruler to slice through the clay to show the fault. Move one side of your clay block
to model each of the three major types of fault movement. Then answer these
questions:
1. What motions did you use to demonstrate each kind of fault?
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
2. What would you expect the ground to look like after an earthquake
on each kind of fault?
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
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FORMING FAULTS
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Copyright 2007 The American National Red Cross
Home Hazard Hunt
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Name ________________________________________________________________________
Anything that can move, fall, break or cause a fire could be a hazard during
an earthquake. Imagine what would happen if you picked up each room in
your home and shook it.
Think about where family members spend the most time and make sure
these areas are safe from falling objects. Make sure exits are clear, too. Use
the following pictures to help you consider the hazards you might find.
For more information, use the Earthquake Safety Checklist (from the
Masters of Disaster CD-ROM), visit www.redcross.org or contact your local
American Red Cross chapter.
Are mirrors or pictures hung away
from beds and chairs?
Are bookshelves fastened
securely to the wall?
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HOME HAZARD HUNT
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Copyright 2007 The American National Red Cross
Home Hazard Hunt
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Are entertainment cabinets
bolted to the wall and electronic
equipment secure on the shelves
and behind cabinet doors?
Are beds or chairs a safe distance
from big windows?
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Are there no heavy objects
on shelves above beds or
chairs?
HOME HAZARD HUNT
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Copyright 2007 The American National Red Cross
Home Hazard Hunt
Page 3 of 3
Are cabinets or cupboards
fastened to the wall? Are the
doors locked shut?
Is the water heater
secured to studs?
Your home may not have all the hazards pictured, but it may have other
areas that are unsafe. The best way to test your home for hazards is to sit in
a space where you spend time and look around you. Imagine the room
shaking violently. Could something fall on you? If so, remove or secure it.
Try this exercise all around your home.
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HOME HAZARD HUNT
Masters of Disaster® Earthquakes, Level 2
Copyright 2007 The American National Red Cross
Neighborhood Hazard Hunt
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Name ________________________________________________________________________
Directions: Around your community, there are many objects that could move, fall,
break or cause a fire and damage during an earthquake. Circle each hazard you find.
Then, on the back of the sheet, write a brief description of each hazard and the
problem that could occur.
Adapted from Earthquakes: A Teacher’s Package for K–6 developed by the National Science Teachers Association
with the support of the Federal Emergency Management Agency, revised April 1999.
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NEIGHBORHOOD HAZARD HUNT
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Drill and Evacuation
Checklist
Page 1 of 1
Name ________________________________________________________________________
Directions: It’s important to practice what to do in case of an earthquake; it’s even
more important to improve your skills. Consider each of the questions below after you
complete an earthquake drill and evacuation. Place a check in the box if the answer is
“yes.” Talk about how to improve if the answer is “no.”
Did everyone know to Drop, Cover and Hold On?
❏
Did everyone follow the procedure correctly?
❏
Did everyone take cover no matter where he or she was?
❏
Did everyone know to drop away from windows, light fixtures, glass cases and
other hazards?
❏
Does everyone know what to do if he or she is outside or in a bus or car?
❏
Did everyone remain quietly in his or her safe position?
❏
Were those with special needs able to participate in the drill and evacuation?
❏
Did an adult take emergency information and needs when we evacuated?
❏
Did everyone sit quietly and listen for further directions?
❏
What must we do to improve?
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DRILL AND EVACUATION CHECKLIST
Masters of Disaster® Earthquakes, Level 2
Copyright 2007 The American National Red Cross
Making Waves
Page 1 of 2
Name ________________________________________________________________________
Directions: Waves have specific characteristics, whether on the ocean or in a bottle.
Select and complete one of the experiments below to illustrate how waves work.
Ocean Wave Simulation
Materials:
• 2-liter clear plastic bottle
• Measuring cup
• 5 oz. (150 ml) water
• 5 oz. (150 ml) vegetable oil
• 3–4 drops blue food coloring
Procedure:
Measure about 5 ounces (150 milliliters) of water and pour it into the plastic bottle.
Measure about 5 ounces (150 milliliters) of oil. Place several drops of food coloring into
the oil and pour the mixture into the plastic bottle. The oil will float on top of the water.
Shift the bottle left to right, simulating an ocean wave.
What do you observe about the changing size of waves?
Wave Formation
Materials:
• Bucket, two-thirds full of water
• Pebble
• Baseball bat or stick
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MAKING WAVES
Masters of Disaster® Earthquakes, Level 2
Copyright 2007 The American National Red Cross
Making Waves
Page 2 of 2
Procedure:
Fill the bucket about three-quarters full of water. Set the bucket on a flat surface and
wait while the water becomes still. Drop a pebble in the middle of the water. Watch the
waves form. Describe what happens to the waves farther from the where the pebble was
dropped. Why?
Now, let the water become still once more. Then, strike the bottom side of the bucket to
see how the ripples form. Are the ripples smaller or larger on the side where you struck
the bucket?
Challenge:
If you could conduct this experiment in a pool of water where the depth becomes gradually shallower near the shore, what would happen to the waves as they approached the
land?
The Seiche
Materials:
9″ x 13″ (23 cm x 33 cm) cake pan or plastic container, half-filled with water
Procedure:
Fill the 9″ x 13″ cake pan or plastic container three-quarters full of water. Walk a few
steps. What happens?
Now, stand still. What happens? Why do the waves form? What are their characteristics?
Challenge:
Do you think a seiche is the same as a tsunami? Why or why not?
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MAKING WAVES
Masters of Disaster® Earthquakes, Level 2
Copyright 2007 The American National Red Cross
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