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TECTONICS ROCK
A Facilitator's Guide to Earth Sciences
Our Vision
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1
Science is intrinsic to their lives
and acknowledge the
fundamental importance of a
quality Science education to
prepare young people for our
rapidly changing world.
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Let’s Talk Science is striving to
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programs, research and
advocacy. We exist to motivate
and empower young Canadians
through Science education.
1
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sciences, technology, engineering and
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Developed by Susan O’Leary, Karen Quinn and Darren
Thompson
For
©2001 Let's Talk Science
Current Edition
©2003 Let's Talk Science
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A. Description of Workshop
Overview of Workshop
Grade for Workshop/
Appropriate Age
This activity is
designed for use in
Grade 7-9 classrooms
or with children ages
12 to 14.
This workshop takes your class from
magma to mountains. Drifting back in
time, students will use scientific evidence
to put together a puzzle of „Pangaea‟.
Students gain an understanding of plate
tectonics by demonstrations of
convergent, divergent and transform
plate movements. After creating model
mountains, students become
cartographers by designing and drawing
their own topographic map.
Overall Objectives
Science Topics




Composition of
the Earth‟s
Crust
Pangaea
Plate Tectonics/
Continental
Drift
Topographical
Mapping




To explore the different
layers of the Earth.
To introduce Pangaea and the
continental drift theory.
To discover plate tectonics
and the three different
types of plate movements.
To learn about topographical
mapping.
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B. How to Run This Workshop
Physical Requirements
Students will do activities at their desks in groups of two.
Materials and Set-Up
Note: For more detail, see Kit List
Introduction
Activity #1 – Pangaea
Cross section of
Earth‟s composition
(laminated)
16 bags of fun foam
continents (1 per every pair
of students)
1 bag of fun foam continents
with magnets on the back
(For demonstration on chalk
board)
Beach ball globe
(OPTIONAL)
Activity #2 – Plate
Tectonics
Map of Earth‟s Tectonic
Plates (overhead)
Map of Different Geological
Activities to overlay on the
plates (overhead)
(OPTIONAL)
Plate Boundary Movement
pictures (laminated with
magnets on back for board
OR on overheads)
Laminated map of Canada (1
per every pair of students)
Pangaea Puzzle Task Cards
(16)
Washable markers (16)
Pangaea creatures (16 sets
plus extras)
*Geological Times Data
Sheet (1/student)
1 bag of:
-fun foam tectonics plates
-fun foam land and water
accessories
Activity #3 –
Topographic Map
Sample topographic
maps (1 set/kit)
Picture of mountains (1
set/kit)
16 placemats for making
the mountains
(OPTIONAL)
Sample Styrofoam
model of mountain OR
fun foam model of a
mountain
Laminated example map
with parts (Velcro™)
*Map worksheet
(1/student)
16 bags of:
-1 block of plasticine
-10 toothpicks
-30 cm of heavy fishing
line and 2 craft sticks
-1 ruler
-Coloured markers
Topographical Map Task
Card
*Consumable items
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Timing of Activity
Part of Workshop:
General Introduction
Introduction to Topic and
Explanation of Activities
Activity #1
Activity #2
Activity #3
Wrap-up
Suggested Timing:
5 min.
10 min.
Cumulative Timing:
5 min.
15 min.
20 min.
30 min.
60 min.
5 min.
35 min.
65 min.
125 min.
130 min.
C. Introduction to Topic
Objectives of Introduction
 To introduce Earth Sciences.
 To discover that the Earth has many layers.
Suggested Discussion, Q & A
Today we are going to talk about the Science of the Earth.
Why is this information important to you?
We live on Earth and need to know about what is happening in the area we live.
For instance, it is important to know if a volcano or earthquake is expected to
take place close to us so we can take necessary safety precautions. Sometimes
we can’t predict when things like this will happen.
What do you know about the Earth?
The Earth is made up of layers. Some are liquid, some are solid.
The Earth is made up of plates.
The Earth is a dynamic and changing place – plates are always moving.
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CHOICE: You can use this analogy or come up with one of your own.
It may be helpful to have an example of this chocolate in your kit or
draw what it looks like on the board.
You can think of the Earth as a Ferrero Rocher chocolate -the gold wrapping
represents our protective atmosphere. The outer layer of the chocolate is hard and
has many different heights. This “crust” is similar to the Earth‟s crust. Inside, is a
softer chocolate much like molten lava and the core of the Earth is hard much like
the nut in the middle of the chocolate.
Can anybody tell me which scientist studies the Earth?
A geologist studies the Earth.
DELIVERY HINT: While you are talking about the different parts of
the Earth (crust, mantle, core), if you mention thicknesses etc., be
sure to emphasize that these are estimates only (provide a range) and
that we are providing this information based on what we have found.
What are the different parts of the Earth?
(Use the map of the cross section.)
There is a layer around the entire Earth called a crust. It ranges from 6 km
to 90 km in thickness. It is thicker where the continents are and thinner
where the oceans are. Beneath the crust is a layer of hot rock called the
mantle. The mantle is 3,000 km thick (that would be like driving from
Vancouver to Regina and back to Vancouver or driving from Toronto to Halifax
and back to Toronto) and ranges from 500 to 4,150 degrees Celsius. The top
part of the mantle is solid and this part in combination with the crust is called
the lithosphere. Below the mantle is the Earth’s core. It is mostly made up of
iron and nickel. It is solid in the centre with liquid on the outside. The liquid
outer core is approximately 2,100 km thick and the solid core is about 1,300
km (Toronto, Ontario to Fredericton, New Brunswick) in diameter. The
temperature at the centre of the Earth is 4,000 degrees Celsius and it is solid
because the pressure is too great for the iron and nickel to melt.
(Use the classroom map or laminated maps to point to places mentioned.)
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D. Activities
ACTIVITY #1a: Put Pangaea Together (10 min.)
Oral instructions
Objective of Activity
 To introduce Pangaea and explore the continental drift theory.
Suggested Instructions, Q & A
The first activity we‟re going to do today is a „world puzzle‟ from about 200 million
years ago. In 1915, a German meteorologist named Alfred Wegener made some
interesting conclusions about how the Earth would have looked 200 million years ago
based on a scientific theory called continental drift.
Does anyone know what a continent is?
A continuous mass of land. This is how we divide the land in our world –
Europe, Asia, South America, North America etc.
What is a theory?
A theory is a scientifically acceptable idea developed to explain a phenomenon.
The continental drift theory suggested that about 200 million years ago, there
existed a super continent called Pangaea – meaning “all lands”. According to
Wegener‟s theory, this continent broke into smaller parts each of which drifted to
their present locations.
(Ideas relating to this theory date as far back as 1620 when an English philosopherscientist named Francis Bacon was the first person to recognize that the continents
fit together. As well, in the early 1900s, Robert Taylor, a geologist who was trying
to explain how mountains were formed was the first to put forth the theory of
continental drift.)
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In groups of two, see if you can solve the world puzzle from 200 million years ago by
using the pieces you have to put the continents back together in one piece.
(Each of the continents will be labeled with North America, South America, etc.)
DELIVERY HINT: Go over directions (north, south, east and
west) before you begin this activity by writing a diagram on the
board. Some students may not be comfortable with this.
ACTIVITY #1b: Put Pangaea Together Using Clues
(10 min.) Use Pangaea Puzzle Task Card
Oral instructions
What sorts of clues did you use to put together your puzzle?
Shape, colour, patterns etc.
When Alfred Wegener published his theory of continental drift, he used geological
and meteorological clues to prove his theory.
What do geological clues relate to?
History, fossils and structures of the Earth.
What do meteorological clues relate to?
Weather and the atmosphere.
Using the clues provided check your Pangaea Puzzle (in your groups of 2) to see if
the clues provide evidence for your original puzzle solution.
DELIVERY HINT: Go over the first question together as a group
using your fun foam magnetic continent pieces at the front of the
class
(Refer to the Pangaea Puzzle Task Card.)
*Discuss using the large fun foam magnetic continent pieces at the front of the
class. You can also use the beach balls to display the 3-D view of the Earth.
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ACTIVITY #2: Plate Tectonics (30 min.)
Use Geological Times Data Sheet
Use laminated Map of Canada
Objective of Activity
 To introduce the theory of plate tectonics.
 To demonstrate the three plate movements in plate tectonics.
Suggested Instructions, Q & A
Scientists have been studying the Earth for hundreds of years. As the technology
has advanced, so has our knowledge about the Earth; what it is made up of, how it
moves and how it will continue to change.
We have been looking at Pangaea and how the continents have moved to their
current locations. Years ago, scientists called this theory “Continental Drift”
because they thought ONLY the continents were moving.
However, as they continued to study the Earth they discovered that the continents,
the land we live on, is connected to the land underneath the oceans (the sea floor).
Let‟s take a closer look at this connection.
[Refer to the cross section of the Earth.]
The Earth‟s crust covers the entire Earth. You can see that the Earth‟s crust is the
land under the oceans and has been pushed upwards to become the land above sea
level, the land we live on.
Have you ever dropped a hard-boiled egg? What happens to the shell?
It cracks into pieces, some large and some small.
The Earth‟s crust is also broken into several pieces, although it wasn‟t dropped like
the hard boiled egg.
[Refer to the diagram of the Earth‟s plates.]
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Does anyone know what we call these pieces?
Plates
(show overhead of Earth‟s tectonic plates)
(Point out a few plates that are relevant to where you are – don‟t list them all).
The Earth‟s crust has 15 plates, they are: Eurasian, Australian, Cocos, South
American, African, North American, Antarctic, Nazca, Caribbean, Indian, Pacific,
Philippine, Scotia, Arabian and Juan de Fuca.
Some plates, like the Pacific plate are entirely under water. Other plates, like the
North American plate have both land and water on them.
[Refer to the cross section of the Earth‟s composition.]
Once scientists realized that the sea floor and the continents were connected, they
figured that when the continents were moving, the sea floor must be moving as well.
They re-evaluated the theory of continental drift and they came up with a new
scientific theory that discusses the plates of the Earth‟s crust. This new and
current theory is called plate tectonics.
Can anyone guess what tectonics means?
Tectonics in Greek (tektonikos) means ‘to build’ or ‘to put together and take
apart’.
The edges of each plate, where they meet other plates, are called plate boundaries.
CHOICE: There is a lot of information included on the 3 kinds of
plate boundaries. It is your choice how much detail you give the class
– this will depend on their prior knowledge and level of interest.
Also, feel free to add role-playing activities or any other
demonstration or analogy that you find helps students understand.
Demonstration:
There are 3 kinds of plate boundaries we are going to focus on in our next activity.
(Use the fun foam model or pictures on board to demonstrate the 3 different kinds
of plate boundaries.)
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1)
A CONVERGENT BOUNDARY is one where two plates are moving towards
each other. When two continental plates meet or collide the plate material
(Earth‟s crust) gets buckled and folded upwards into mountain ranges (i.e.
Himalayas: Indo-Australian plate crashing into the Eurasian plate).
Earthquakes also result. This is similar to two cars crashing head-on. The
metal wrinkles fold, as the Earth does, forming mountains or rips like an
earthquake.
When a continental plate collides with an oceanic plate, the oceanic plate gets
subducted/pushed under the continental plate. The oceanic plate reheats and melts
as it comes into contact with the molten mantle.
As the continental plate moves over the oceanic plate, it begins to peel the top
layers off the surface. These layers pile up at the edge of the plate. This is how
the Rocky Mountains were formed. Earthquakes (Marianas trench) and volcanoes
(subduction of the Juan de Fuca plate beneath the North American plate) also result
from this type of convergent boundary.
When two oceanic plates collide, one usually subducts. The sinking plate remelts
and, as it is subjected to much pressure, the remelted material comes to the surface
in volcanoes, forming island arcs (i.e. Japan).
2)
A DIVERGENT PLATE BOUNDARY is one where plates move away from each
other. When this occurs underwater (i.e. Mid-Atlantic ridge) hot magma
instantly comes to the surface and spreads out, creating a new ocean floor.
When plates move away from each other under a continent, the crust splits open to
allow magma out. Magma movement may be slow to the surface (warm areas and
geysers/hotsprings) OR the magma might explode, bringing into existence a new
volcano where there was only cool Earth before (i.e. East African Rift Valley).
Divergent Boundaries may result in volcanic eruptions and earthquakes.
3)
The third type of plate movement is called a TRANSFORM BOUNDARY.
If plates do not come together nor move away from each other, how do you
think they move in relation to each other?
They slide alongside each other. Don‟t be fooled by the word slide! When two
plates meet there is great stress on the surface of the Earth. Earthquakes
occur at transform boundaries, but volcanoes are NOT common. Rocks at the
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plate edges (called faults) may be pulverized into powder. (i.e. San Andreas
fault in California: North American plate and the Pacific plate).
Mountains can be formed from transform faults. Grinding stop and start
movement generates great pressure in the plates and can cause cracking.
Activity – Geological Times

Hand out the Data Sheet and give oral instructions for this activity.
Answer the questions on the Data Sheet after reading each article and use the
erasable markers to mark your laminated map. The only thing each student will
keep is the Data Sheet. Students will not keep the maps.
Activity Wrap-up
For a review, what are the three types of plate movements?
Divergent, convergent and transform boundaries.
* Take up the “Geological Times” activity using answers from the data sheet.
Canadian Scientist One of the Great Leaders
Transform boundary
New Island Created!
Divergent boundary – volcanic eruption and lava build-up.
Rocky Roads Ahead
Convergent boundary – subduction of the Pacific Plate underneath the North
American Plate.
Safest Place to Live in Canada
Transform boundary – Queen Charlotte Fault (Pacific Plate and North American
Plate) or Convergent Boundary
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ACTIVITY #3 – Topographical Maps (60 min.)
Use laminated Topographical Demonstration Map
Use Map Worksheets
Use Topographical Map Task Cards
Objective of Activity
 To create a topographical map.
 To discover the different parts of a topographical map.

Suggested Instructions, Q & A
With the last activity we learned about the movement of different plates. In this
part of the workshop, we will focus on mountains.
Does anybody remember what kind of plate movements can create mountains?
Convergent boundaries (plates that push together) are the plate movements that
usually create mountains.
Does anybody know where we can find the tallest mountain in the world?
Mount Everest in the Himalayas found in Nepal. It is growing all the time
because the plates are pushing together to make it taller. If you count from
the bottom of the ocean, the Hawaiian islands from base (under water) to top
are higher.
Does anybody know where we can find the tallest mountain in Canada?
Mount Logan in the Yukon.
What are some mountain ranges in Canada?
The Rockies, the Laurentians and the Appalachians
How can we illustrate a tall mountain on a flat piece of paper?
Colours, symbols (∆∆∆) or special maps called topographic maps.
[Compare 3-D model of a mountain made of layers of Styrofoam to a 2-D model of a
topographical map.]
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How do you think we can represent the height of a mountain using a topographic
map? There are special lines on topographic maps called contour lines.
Contour lines are labelled to show the height of land. In a topographic map, 0
metres is sea level. If a contour is labelled 100 metres we know that every place
along the line is 100 metres above sea level.
[Split apart 3-D mountain into its different segments –6 segments total.]
Let‟s say that each one of these segments (or contour lines) is 100 metres. If there
are 6 segments or contour lines, how tall would my mountain be?
600 metres.
[Use the 3-D mountain and the laminated hand-made map (it would be taped to the
board)]
As you can see from the map on the board, we don‟t need a 3-D model of a mountain
to understand the height of a mountain. (If you need, show how you would trace the
contour line by placing the 3-D map segments on the hand-made map.) Each contour
line represents an increase in elevation by regular intervals (100 m, 200 m, 300 m
etc.).
If we know that each contour line on our map represents 100 m, how tall is our
mountain?
By counting the contour lines, we can see that there are 6 lines. Therefore,
the mountain is at least 600 metres (the actual peak may be higher than 600 m
but it is less than 700 m).
Why do you think that we need topographic maps?
We can use topographic maps for hiking, camping, canoeing, fishing and
orienteering. Topographic maps are also used for urban planning, resource
development and surveying.
Topographic maps are important because they represent the Earth‟s features
accurately and to scale on a two dimensional surface.
(Point to the hand-made topographic map on the board.)
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On our map we have our contour lines and a map border. What parts of the map are
we missing?
The components are north arrow, title, date, author, scale, contour interval and
legend. (Additional information about scale, legend and north arrow are provided in
section F.)
* as students mention the different parts – you can attach these parts to the map.
Activity
DELIVERY HINT: You could suggest to the teacher that they
may want to collect these maps as a form of assessment.
DELIVERY HINT: You may want to emphasize that for their own
mountains, the contour interval will be a made-up number that
they decide on (i.e. 100 m, 500 m). Also, clearly explain the
difference between SCALE and CONTOUR INTERVAL (see
background information section).
(Show students bags of supplies for topographic map making.)
As you can see, each group will be given a plastic bag with some plasticine and other
supplies. With the plasticine you will design a model of a mountain.
What is a model?
In this case, it is a small-scale representation of the real mountain.
Working with a partner, each of you will create a topographic map using the
materials provided. One group member will create a STEEP MOUNTAIN and the
other member will create a GENTLE SLOPE.
Hand out Topographical Map Task Cards but go over them with the class first.
Don‟t forget to include a north arrow, scale, legend, authors, title, contour interval
and date – you can refer to the map on the board for help. Please don‟t squash your
model mountain. We will need them for later.
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(Hand out bags with supplies and blank photocopied map.)
Activity Wrap-up
What does it mean when the contour lines on a topographic map are close together ?
It means that the mountain is very steep.
What does it mean when the contour lines on a topographic map are very far apart?
It means that the mountain has a very gentle slope.
* Demonstrate this by comparing two different plasticine mountains (i.e. the steep
mountain and the gentle slope) and the topographic maps they have made.
Being close to a mountain can affect the people around it and their lifestyle. Often
times, these people can use a topographic map to make their life easier. For
example:
How might you use a topographic map if you were selecting a route for a hike?
Choose a route that’s not too steep.
How might you use a topographic map to find the best location for an airport?
Make sure that airplanes have plenty of room to take off and land before the
ground rises.
How might you use a topographic map to find a route for a new road?
Choose an area that has a gentle slope rather than a steep slope.
Try to think of the people that live near mountains. What could they do as jobs?
What could they do for fun? How do you think the mountain affects their lifestyle?
Jobs: ecotourism (park naturalist), instructors for climbing and skiing etc.,
search and rescue.
Fun: skiing, hiking, climbing.
There are many, many examples for both.
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E. Wrap-Up




What was your favourite activity today?
Do you think Science is fun?
Do you like Science?
Do you have any questions for me?
F. Glossary
Continental Drift
The slow movement of the continents across the surface of the Earth due to the
motion of the underlying tectonic plates.
Convergent Boundary
When two plates are moving towards each other. This can occur with two
continental plates collide OR when a continental plate collides with an oceanic plate
OR when two oceanic plates collide.
Divergent Boundary
When plates move away from each other. This can occur underwater OR under a
continent.
Earthquakes
Sudden movements of the Earth‟s crust caused by the plates moving against one
another.
Earth’s Crust
The outer “skin” of the Earth, consisting of large plates of rock which are floating
on the mantle.
Hot Spot
A location on Earth where the temperature of the material under the crust is much
higher than elsewhere. As a result, lava or magma is forced upward through cracks in
the crust. This is how Hawaii was formed.
Lava
Hot molten rock that is above the surface of the Earth.
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Magma
Hot molten rock that originates from the Earth‟s mantle.
Mantle
A thick layer of dense, semi-liquid rock which extends some 3000 km below the
Earth‟s crust.
Plate Boundaries
Areas of volcanic and earthquake activity where tectonic plates meet.
Richter Scale
A logarithmic scale of 1 to 10 used to compare the magnitude of earthquakes.
Subduction
The dipping of one plate below another at a convergent plate boundary.
Tectonic Plates
Huge sections of the Earth‟s crust which move across the underlying mantle.
Transform Boundary
When two plates slide alongside of each other.
G. Background Information
Pangaea/Theory of Plate Tectonics
With the advent of improved world maps, a few people looked at the world and
thought that there were some places that looked like the continents would fit
together like puzzle pieces. In 1915, a meteorologist named Alfred Wegener
published his theory of Continental Drift. He suggested that about 200 million years
ago there existed a super-continent that he called Pangaea (meaning all-land). It
broke into smaller pieces and drifted to its present locations. To prove his theory he
used the fit of Africa and South America, climatic data, rock structures and fossil
evidence.
Wegener's idea was NOT well accepted in the scientific community. When he died in
1930 most still did not believe his theory because he still could not explain HOW the
continents moved.
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In the 1950s and 60s, scientists started using continental shelf edges to examine
the fit of the continents. It was VERY close. There were also great advances in
exploring the sea floor. They found rifts and earthquakes on the sea floor. But they
did NOT find any old rock. This led to the theory of sea floor spreading, as the
ocean always seems to be creating new rock.
In 1968, continental drift and sea floor spreading were combined to help form the
plate tectonics theory. A Canadian named John Tuzo Wilson was one of the main
scientists working on the theory. Plate tectonics states that the outer rigid
lithosphere (crust and part of mantle) are made up of individual segments, or plates.
These plates often include some oceanic and some continental crust, unlike
continental drift where the continents themselves were thought to be the only
things moving.
What causes the plates to move?
Scientists are not exactly sure. One explanation is that convection currents in the
mantle cause the Earth‟s crust (plates) to move. Heat and pressure cause the molten
rock beneath the Earth‟s crust to boil and flow. The energy to cause these
convection currents and in turn plate movements may come from several sources
within the Earth:

Radioactivity within the Earth

Meteoric bombardment of Earth

Gravity and the pressure it puts on Earth‟s interior
If the ocean floor spreads, why doesn’t the water fall into the holes? Water
can‟t fall into the holes because tremendous pressure forces molten rock from the
mantle to erupt through the rifts and doesn‟t stop to allow even a drop of water in.
A totally new plate boundary appears when a continent starts to rift apart. Today,
the continent of Africa is splitting apart along the African Rift Valley to make a new
plate boundary. Continental lithosphere has broken right through. Sometime in the
future, a new ocean may separate East Africa from the rest of the continent.
Earth‟s plates move at a rate of approximately 2-12 cm per year.
Earthquakes
 Occur all over the world
 Most occur on active faults that define the major tectonic plates
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





The „ring of fire‟ circling the Pacific Ocean (incl. Canada‟s west coast) is one of
the most active areas in the world.
Largest earthquake ever recorded – 9.5 magnitude off the coast of Southern
Chile on May 22, 1960.
Most earthquakes that occur in Canada occur along the active plate boundaries
off the B.C. coast and along the Northern Cordillera (SW corner of the Yukon
Territory and the Richardson Mountains and Mackenzie Valley) and Arctic
margins (incl. Nunavut and N. Quebec)
Magnitude is determined using a seismograph, recording the amplitude of the
ground shaking and correcting this distance from the earthquake source.
Intensity refers to how the quake is felt at various locations
Human activities can trigger earthquakes! – filling in reservoirs and the injection
of fluids into wells for oil recovery or waste disposal
Difference between continental crust and oceanic crust
 Oceanic crust is very dense (basaltic)
 Continental crust (granitic) is not as dense as the oceanic crust. It extends out
into the ocean 200 miles/320 km before sloping off.
 The continental crust under the water is known as the continental shelf
Volcanoes
A volcano is a gap in the Earth‟s crust from which molten rock, ash and gases (steam,
carbon and sulfur dioxides, carbon monoxide, hydrogen chloride) flow or burst
depending on the type of volcano and the pressure involved.
Some volcanoes occur at the edge of tectonic plates. As the plates collide, one is
subducted (pushed underneath the other). The rock that is subducted remelts to
form magma. It can burst up through the surface, creating a volcano.
Other volcanoes form under the oceans, when magma gushes up from underneath the
oceanic crust.
The molten rock in the magma chamber is lighter than the surrounding rock because
solid rock expands when it melts. As it expands, the molten rock (magma) moves
upward. When the magma reaches the Earth‟s surface it is called lava. The lava cools
and solidifies (sometimes slowly and sometimes quickly).
Volcanic activity can create earthquakes, avalanches, landslides, mudslides and
tsunamis (tidal waves).
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An extinct volcano, if such a thing exists – and only time will tell – is a truly dead
volcano. The volcano isn‟t located in an area of likely activity and there is no record
of activity in years!!! Because of constant plate movement, an extinct volcano might
always roar back to life.
Where are volcanoes located?
Most volcanic sites are areas where the Earth‟s tectonic plates come together/move
apart. The Pacific region hosts the largest concentration of volcanoes, called the
„ring of fire‟.
Is there a link between earthquakes and volcanoes?
YES! The movements of Earth‟s tectonic plates cause both earthquakes and
volcanoes.
Are there volcanoes in Canada?
Yes, there are many volcanoes in and near B.C.
Volcanoes occur where the Earth‟s crust is being stretched and pulled apart, and new
crust is formed, such as along the undersea Juan de Fuca Ridge west of Vancouver
Island. These areas of stretching can also occur on the continents. Such a region is
found in north western British Columbia and forms a chain of volcanoes referred to
as the Stikine Volcanic Belt. One of the most notable volcanoes in this chain is Mount
Edziza, now a provincial park because of its incredible beauty.
The third type of volcanic area forms where ocean crust is pushed down below
continental crust in a subduction zone. A subduction zone runs along the coast of
North America from northern California to the northern end of Vancouver Island.
The most recently active volcano in this chain is Mount St. Helens in Washington
State. Volcanoes in Canada which are part of this chain include Mount Garibaldi,
Mount Cayley and Mount Meager. Of these, the most recently active is Mount
Meager which had a very large eruption (probably similar to the 1980 eruption of
Mount St. Helens) about 2,300 years ago. This eruption spread ash across British
Columbia into Alberta.
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Heights of Mountains
The website that lists (in order) the world's highest mountains is:
http://infoplease.lycos.com/ipa/A0001771.html
Mountain peak
Everest
K2 (Godwin Austen)
Range
Himalayas
Karakoram
Location
Nepal/Tibet
Pakistan/China
Height
ft.
m
29,035
28,250
8,850
8,611
North Arrow
Even if there is no north arrow on the map, it is convention that north is always at
the top of the page unless otherwise indicated.
There is a difference between true north and magnetic north. Since most
topographic maps are used for orienteering, they have both the directions of true
north and magnetic north. That way people can make adjustments with their
compass.
Scale
To make the map a more convenient size, features on a map must be proportionally
smaller than they really are. The proportion chosen for a particular map is its scale.
The scale is the relationship between the distance on the map and distance on the
ground. It is usually given in a fraction or a ratio – 1/10,000 or 1:10,000. The first
number (map distance) is always 1. The second number (ground distance) is different
for each scale. The larger the second number, the smaller the scale of the map.
Topography
Possible websites for more information:
http://www.usgs.gov/education/teacher/what-do-maps-show/WDMS4.html
http://mac.usgs.gov/mac/isb/pubs/booklets/symbols
The word “topographic” is derived from two Greek words – “topo” meaning “place”
and “graphos”, meaning “drawn” or “written”.
The distinctive characteristic of a topographic map is that the shape of the Earth‟s
surface is shown by contour lines. Contour lines are imaginary lines that join points
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of equal elevation on the surface of the land above or below a reference surface
such as sea level. Think of a contour line as an imaginary line on the ground that
takes any path to maintain constant elevation. Contours make it possible to measure
the height of mountains, depths of ocean bottom and steepness of slopes. A
topographic map shows more than contours. The map includes symbols that
represent such features as streets, buildings, streams and woods. (Contour lines are
usually brown and blue lines mean rivers/lakes).
Contours that are very close together represent steep slopes. Widely spaced
contours, or an absence of contours, means that the ground slope is relatively level.
The elevation difference between adjacent contour lines, called the contour interval,
is selected to show the general shape of the terrain. A map of a relatively flat area
may have a contour interval of 10 feet (3.05 m) or less. Maps of mountainous areas
may have contour intervals of 100 feet (30.5 m) or more.
Topographic maps are used at all levels of government and industry for food control,
forest fire control, real estate planning, development of natural resources,
environmental issues, right-of-way, highway planning and depiction of crop areas.
H. Suggested Resources
Websites
www.usgs.gov
www.infocan.gc.ca/facts/geography_e.html
www.seismo.nrcan.gc.ca/questions/faq_e.html
www.extremescience.com/PlateTectonicsmap.htm
www.encarta.msn.com
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Books
Pictures of mountains provided by:
Steve Westley
Policy & Product Promotion
Centre for Topographic Information
Natural Resources Canada
711 - 615 Booth Street
Ottawa Canada K1A 0E9
Tel: 613-947-0571 Fax: 613-947-2189
<mailto:[email protected]>
<http://maps.NRCan.gc.ca/>
Kendra, M. and Williams, P. (1992). Science Wizardry for Kids.
New York: Barron‟s Educational Series, Inc.
ISBN: 0-8120-4766-4
Alvens, C. (1994) Meteorology Today: An Introduction to Weather, Climate and the
Environment – 5th edition.
Minneapolis: West Publishing Company.
ISBN: 0-314-02779-3
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