The lab directly following, entitled, “Piecing Together the Plates” can be used as a stand alone activity,
but would make more sense to the students if it followed a unit/lesson plans on plate tectonics,
specifically the different boundary types. For 3 possible lesson plans to incorporate into this unit, please
see the following pages after the “Piecing Together the Plates” lesson plan. (The Earth’s Plates, Snack
Tectonics, Egg Plates).
Laboratory Title: Piecing Together the Plates
Your Name: Lisa McCready
Concepts Addressed: Tectonic Plates; Continental and Oceanic Plates, Plate Boundaries
Lab Goals: Students will build a knowledge base surrounding the actual plate names and the
boundaries located at the edges of the plates
Lab Objectives: Students will…

Identify the world continents and oceans

Provide an example of a world map with their estimation of the location of the 15 major plates

Compare their estimation to the actual plate locations

Predict certain boundary types based on plate tectonic clues

Discuss/share with class/classmates what transpires at the different boundaries

Work cooperatively with partners
SCIENCE Benchmark(s) Addressed (3rd to 4th Grade):
3.1 Structure and Function: Living and non-living things vary in their characteristics and
properties.
3.1P.1 Compare and contrast the properties of states of matter.
3.2 Interaction and Change: Living and non-living things interact with energy and forces.
3.2P.1 Describe how forces cause changes in an object’s position, motion, and speed.
3.4 Engineering Design: Engineering design is a process that uses science to solve problems or
address needs or aspirations.
3.4D.3 Give examples of inventions that enable scientists to observe things that are too small or too far
away.
4.1 Structure and Function: Living and non-living things can be classified by their characteristics
and properties.
4.1E.1 Identify properties, uses, and availability of Earth materials.
4.2 Interaction and Change: Living and non-living things undergo changes that involve force and
energy.
4.2P.1 Describe physical changes in matter and explain how they occur.
4.2E.1 Compare and contrast the changes in the surface of Earth that are due to slow and rapid
processes.
4.3 Scientific Inquiry: Scientific inquiry is a process of investigation through questioning, collecting,
describing, and examining evidence to explain natural phenomena and artifacts.
4.3S.3 Explain that scientific claims about the natural world use evidence that can be confirmed and
support a logical argument.
Materials and Costs:
List the consumable supplies and estimated cost for presenting to a class of 30 students
Pencils (.10 x 30) ...................................................................................................$3.00
Tracing paper (1 answer key per student, pack of 40 sheets for 2.99) ..................$2.99
Tape (A couple of rolls, the students can share/pass around, 2.08 x 3) .................$6.24
Paper – World Continents and Oceans map (I bought preprinted packet, 50
sheets) ....................................................................................................................$6.99
Paper – Naming your Plates Activity (.01 x 30) ....................................................$0.30
Paper – What’s Going on at Some of Our Borders Activity (.01 x 30) .................$0.30
Paper – Create Your Own Phrase Activity (.01 x 30)............................................$0.30
Paper – Test Your Plate Knowledge Activity (4 pages per student, .01 x 120 ......$1.20
Paper – Quiz (.01 x 30) ..........................................................................................$0.30
Estimated total, one-time, start-up cost: ..............................................................$21.62
**If I had more money, or was an actual teacher and would be doing this activity multiple times, I
would create the answer keys on transparency/overhead paper instead of tracing paper. This
would allow a one time building of an answer key and photocopying it onto the transparency
paper. Those answer keys could then be used over and over and could be written on with dry
erase pens!
Time:
Initial Preparation time: Teacher has to create an outline of plates based on map you are using as
background, then, trace an answer key for each student. Buy supplies. Make copies.
60 – 90 minutes
Preparation time: Getting supplies together.
10 minutes
Instruction time: This depends on what activities you want to include.
30 minutes
Clean-up time:
5 minutes
Assessment (include all assessment materials):
1. Name 2 continental plates and their approximate location.
2. Draw/sketch a plate boundary type and write its name and a landform or geological activity that
can occur there.
3. What was the most interesting thing you learned during this unit?
ACTIVITY INSTRUCTIONS (Based on a 30 minute timeframe):
1. Introduce information to class. (Via PowerPoint). Approximately 5 minutes.
2. Briefly describe to the class what the complete activity will be and then provide guidance as the
students work through the different parts of the activity.
3. Provide each student with a pencil.
4. Hand out the blank “World Continents and Oceans” paper.
5. Have the students label the continents and oceans.
6. Have the students draw, using a pencil, on their map what they think the plate boundaries are for
the 15 plates being studied. Emphasize that it does not matter how close they are, it is just to get
an idea of where they think the boundaries lie on our Earth. You can suggest that they number
their plates so they can tell if they have mapped 15 of them. Approximately 3 minutes.
7. Have the students raise their hand when they are done and then provide them with an outline
(transparency) to place over their maps to show them the real plate boundaries. They will also be
given the next activity (NAMING YOUR PLATES). Tell the students that they should feel free
to work with a partner to work through the rest of the activities. Approximately 3 minutes.
8. Walk around the classroom as the students are working through their activities to make sure they
understand what they are doing and that they stay on task.
9. Have the students raise their hands as they finish the activities.
10. Hand out the “WHAT’S GOING ON AT SOME OF OUR BORDERS” activity. Approximately
3 minutes.
11. Hand out the “CREATE YOUR OWN PHRASE TO REMEMBER THE NAMES OF THE
PLATES” activity. Approximately 5 minutes.
12. End activity with a review which must include (Done via PowerPoint, approximately 5
minutes):
a. Master map showing the students the names of the plates so they can compare their map
to the answer key.
b. Show on the map the 3 boundaries they were to figure out and discuss as a group the
correct answers.
c. Allow students to share their “phrases” they came up with to remember the names of the
plates.
d. QUESTIONS!
Naming Your Plates
While there are more than 15 plates, we are focusing on 15 of the most common continental and oceanic
plates.
Using the clues below, write the names of the plates on your transparency!
1. African – This plate covers more than just the continent of Africa.
2. Antarctic – This plate is the 5th largest plate in the world and is in the Southern Hemisphere.
3. Arabian – This plate is mainly covering the Arabian Peninsula.
4. Australian – This plate covers more than just the continent of Australia.
5. Caribbean – This plate is mostly oceanic and is touching the southern end of the plate which
covers the continent on which we live.
6. Cocos – This is an oceanic plate and likes to snuggle up next to the Caribbean plate.
7. Eurasian – This is a tectonic plate that covers two continents, whose names can be figured out by
breaking apart the name of the tectonic plate.
8. Indian – This plate covers the country of the same name, minus an “n.”
9. Juan De Fuca – This plate is very small and is located along the western coast of our country.
10. Nazca – This is an oceanic plate. Its northern border touches the Cocos plate southern border.
11. North America – YOU LIVE HERE! It gets labeled 2 times on your map.
12. Pacific – This is an oceanic plate. It gets labeled 3 times on your map.
13. Philippine – This plate is in between the Pacific plate and the Eurasian plate.
14. Scotia – This is an oceanic plate in the southern hemisphere and touches the 5th largest plate in
the world.
15. South American – This plate is between the African and Nazca plates.
What’s Going on at Some of Our Borders?
Remember the names of our tectonic plate boundaries…
Convergent
Divergent
Transform
1. The following landform is along the border of the South American plate and the African plate:

A portion of the Mid Atlantic Ridge
Using this information, please make note on your transparency along the border between
the South American and African Plate, as to the type of boundary.
2. The following tectonic activity and landforms have been created along the border between the
Juan de Fuca plate and the North American plate:

Subduction

Cascade Range Volcanoes

Pacific Ring of Fire
Using this information, please make note on your transparency along the border between
the Juan de Fuca plate and the North American plate, as to the type of boundary.
3. Located in California, as part of the North American Plate, the following can be found:

San Andreas Fault

Earthquakes
Using this information, please make note on your transparency somewhere in the vicinity
of California, as to the type of boundary.
Create Your Own Way To Remember the Names of the Plates!
Use the following information to come up with a phrase, a song, or something with meaning to you, to
help you remember the names of the 15 most common plates!
MAJOR:
African, Antarctic, Australian, Eurasian, Indian, North American, Pacific, South American
MINOR:
Arabian, Caribbean, Cocos, Juan de Fuca, Nazca, Philippine, Scotia
7 CONTINENTS:
North America, South America, Africa, Europe, Asia, Australia, Antarctica
The following websites can be used as a reference for material to use in lectures, lesson plans,
visuals, videos, etc, associated with Plate Tectonics/Continental Plates. Many of the websites
contain the same information, but different people retain and digest information in different ways,
so these websites should give you a great variety of ways to understand the information yourself
and a variety of ways to share it with your students.
http://www.learner.org/interactives/dynamicearth/index.html
http://www.uky.edu/AS/Geology/howell/goodies/elearning/module04swf.swf
http://jclahr.com/science/earth_science/cr06/workshop/activities/snack/snack_tectonics.html
http://www.pbs.org/wgbh/aso/tryit/tectonics/
http://thinkfinity.org/PartnerSearch.aspx?Search=True&orgn_id=7&subject=all&partner=all&resource_type=all&
q=geology&grade=3%2c5
http://www.usgs.gov/
http://pubs.usgs.gov/gip/dynamic/tectonic.html
http://pubs.usgs.gov/gip/dynamic/slabs.html
http://en.wikipedia.org/wiki/Plate_tectonics
http://en.wikipedia.org/wiki/List_of_tectonic_plates
http://www.enchantedlearning.com/subjects/astronomy/planets/earth/Continents.shtml
http://www.platetectonics.com/book/page_2.asp
http://www.moorlandschool.co.uk/earth/tectonic.htm
http://hypertextbook.com/facts/ZhenHuang.shtml
http://uk.encarta.msn.com/media_1041500150/map_of_major_tectonic_plates.html
http://volcano.oregonstate.edu/vwdocs/vwlessons/plate_tectonics/part12.html
http://esa21.kennesaw.edu/activities/tectonics/plate_mechanics.pdf
http://www.extremescience.com/PlateTectonicsmap.htm
http://webspinners.com/dlblanc/tectonic/ptABCs.php
http://uk.video.yahoo.com/watch/1595682/5390276
http://uk.video.yahoo.com/watch/2654247/7779721
http://www.kidsknowit.com/educational-songs/play-educational-song.php?song=Cuida%20Nuestro%20Mundo
Books Referenced:
Bower, Sue., Restless Earth, A Beginner’s Guide to Plate Tectonics, DK Essential Science, New York, 16-37 pp., 2002.
Following is information about the 15 plates covered in this lesson plan. I used this information,
along with a map of the plates, to come up with my questions on the worksheet, “Naming Your
Plates.” The information can be used in other ways to supplement your individual needs/lecture.
The information came from Wikipedia. The link can be found at the end of the data.
Image above: http://www.learner.org/interactives/dynamicearth/plate.html
The African Plate is a tectonic plate which includes the continent of Africa, as well as oceanic crust
which lies between the continent and various surrounding ocean ridges.
The westerly side is a divergent boundary with the North American Plate to the north and the South
American Plate to the south forming the central and southern part of the Mid-Atlantic Ridge. The
African plate is bounded on the northeast by the Arabian Plate, the southeast by the Indo-Australian
Plate, the north by the Eurasian Plate and the Anatolian Plate, and on the south by the Antarctic Plate.
All of these are divergent or spreading boundaries with the exception of the northern boundary with the
Eurasian Plate (except for a short segment near the Azores, the Terceira Rift).
The African Plate's speed is estimated at around 2.15 centimeters per year. It has been moving over the
past 100 million years or so in a general northeast direction. This is drawing it closer to the Eurasian
Plate, causing subduction where oceanic crust is converging with continental crust (e.g. portions of the
central and eastern Mediterranean).
The Antarctic Plate is a tectonic plate covering the continent of Antarctica and extending outward
under the surrounding oceans. The Antarctic Plate has a boundary with the Nazca Plate, the South
American Plate, the African Plate, the Indo-Australian Plate, the Scotia Plate and a divergent boundary
with the Pacific Plate forming the Pacific-Antarctic Ridge.
The Antarctic plate is roughly 60,900,000 square kilometers[1]. It is the fifth biggest plate in the world.
The Antarctic plate movement is estimated at least 1 centimeter/per year towards the Atlantic Ocean.
The Arabian Plate is one of three tectonic plates (the African, Arabian and Indian crustal plates) which
have been moving northward over millions of years toward an inevitable collision with Eurasia. This is
resulting in a mingling of plate pieces and mountain ranges extending in the west from the Pyrenees,
crossing southern Europe and the Middle East, to the Himalayas and ranges of southeast Asia. [1]
The Arabian Plate consists mostly of the Arabian peninsula; it extends northward to Turkey. The plate
borders are:




East, with the Indo-Australian Plate
South, with the African Plate to the west and the Indo-Australian Plate to the east
West, a left lateral fault boundary with the African Plate called the Dead Sea Transform (DST),
and a divergent boundary with the African Plate called the Red Sea Rift which runs the length of
the Red Sea;
North, complex convergent boundary with the Anatolian Plate and Eurasian Plate.
The Arabian Plate was part of the African plate during much of the Phanerozoic Eon (Paleozoic Cenozoic), until the Oligocene Epoch of the Cenozoic Era. Red Sea rifting began in the Eocene, but the
separation of Africa and Arabia occurred in the Oligocene, and since then the Arabian Plate has been
slowly moving toward the Eurasian Plate.
The collision between the Arabian Plate and Eurasia is pushing up the Zagros Mountains of Iran.
The Indo-Australian Plate is a major tectonic plate that includes the continent of Australia and
surrounding ocean, and extends northwest to include the Indian subcontinent and adjacent waters.
Recent studies suggest that the Indo-Australian Plate may be in the process of breaking up into two
separate plates due primarily to stresses induced by the collision of the Indo-Australian Plate with
Eurasia along the Himalayas. [1] The two protoplates or subplates are generally referred to as the Indian
Plate and the Australian Plate.
India, Meganesia (Australia, New Guinea, and Tasmania), New Zealand, and New Caledonia are all
fragments of the ancient supercontinent of Gondwana. Seafloor spreading separated these land masses
from one another, but as the spreading centers became inactive they fused into a single plate.
Recent GPS measurement in Australia confirms the plate's movement as being 35 degrees east of north
with a velocity of 67 mm/yr. Note also the same directions and velocities for points at Auckland,
Christmas Island and southern India. The slight change in direction at Auckland is presumably due to a
slight buckling of the plate there, where it is being compressed by the Pacific Plate.
The southeasterly side is a complex but generally convergent boundary with the Pacific Plate. The
Pacific Plate subducting under the Australian Plate forms the Tonga and Kermadec Trenches, and the
parallel Tonga and Kermadec island arcs. It has also uplifted the eastern parts of New Zealand's North
Island.
The continent of Zealandia, which separated from Australia 85 million years ago and stretches from
New Caledonia in the north to New Zealand's subantarctic islands in the south, is now being torn apart
along the transform boundary marked by the Alpine Fault.
South of New Zealand the boundary becomes a transitional transform-convergent boundary, the
Macquarie Fault Zone, where the Australian Plate is beginning to subduct under the Pacific Plate along
the Puysegur Trench. Extending southwest of this trench is the Macquarie Ridge.
The southerly side is a divergent boundary with the Antarctic Plate called the Southeast Indian Ridge
(SEIR). The westerly side is a transform boundary with the Arabian Plate called the Owen Fracture
Zone, and a divergent boundary with the African Plate called the Central Indian Ridge (CIR). The
northerly side of the Indo-Australian Plate is a convergent boundary with the Eurasian Plate forming the
Himalaya and Hindu Kush mountains.
The northeast side of the Indo-Australian plate forms a subducting boundary with the Eurasian plate on
the borders of the Indian Ocean from Bangladesh, to Myanmar (formerly Burma) to the south-west of
Indonesian islands of Sumatra and Borneo.
The subducting boundary through Indonesia is not parallel to the biogeographical Wallace line that
separates the indigenous fauna of Asia from that of Australasia: the Eastern islands of Indonesia lie
mainly on the Eurasian Plate, but have Australasian-related fauna and flora.
The Caribbean Plate is a mostly oceanic tectonic plate underlying Central America and the Caribbean
Sea off the north coast of South America.
Roughly 3.2 million square kilometers (1.2 million square miles) in area, the Caribbean Plate borders the
North American Plate, the South American Plate, the Nazca Plate and the Cocos Plate. These borders
are regions of intense seismic activity, including frequent earthquakes, occasional tsunamis,[1] and
volcanic eruptions.
The northern boundary with the North American plate is a transform or strike-slip boundary which runs
from the border area of Belize, Guatemala (Motagua Fault), and Honduras in Central America, eastward
through the Cayman trough on south of the southeast coast of Cuba, and just north of Hispaniola, Puerto
Rico, and the Virgin Islands. Part of the Puerto Rico Trench, the deepest part of the Atlantic Ocean
(roughly 8,400 meters), lies along this border. The Puerto Rico trench is at a complex transition from the
subduction boundary to the south and the transform boundary to the west.
The eastern boundary is a subduction zone, but since the boundary between the North and South
American Plates in the Atlantic is as yet undefined, it is unclear which one, or possibly both, is
descending under the Caribbean Plate. Subduction forms the volcanic islands of the Lesser Antilles
island arc from the Virgin Islands in the north to the islands off the coast of Venezuela in the south. This
boundary contains seventeen active volcanoes, most notably Soufriere Hills on Montserrat, Mount Pelée
on Martinique, La Grande Soufrière on Guadeloupe, Soufrière Saint Vincent on Saint Vincent, and the
submarine volcano Kick-'em-Jenny which lies about 10 km north of Grenada.
Along the geologically complex southern boundary the Caribbean Plate interacts with the South
American Plate forming Barbados, Trinidad (both on the South American Plate) and Tobago (on the
Caribbean Plate), and islands off the coast of Venezuela (including the Leeward Antilles) and Colombia.
This boundary is in part the result of transform faulting along with thrust faulting and some subduction.
The rich Venezuelan petroleum fields possibly result from this complex plate interaction.
The western portion of the plate is occupied by Central America. The Cocos Plate in the Pacific Ocean
is subducted beneath the Caribbean Plate, just off the western coast of Central America. This subduction
forms the volcanoes of Guatemala, El Salvador, Nicaragua, and Costa Rica, also known as the Central
America Volcanic Arc.
The Cocos Plate is an oceanic tectonic plate beneath the Pacific Ocean off the west coast of Central
America, named for Cocos Island, which rides upon it.
The Cocos Plate is created by sea floor spreading along the East Pacific Rise and the Cocos Ridge,
specifically in a complicated area geologists call the Cocos-Nazca spreading system. From the rise the
plate is pushed eastward and pushed or dragged (perhaps both) under the less dense overriding
Caribbean Plate, in the process called subduction. The subducted leading edge heats up and adds its
water to the mantle above it. In the mantle layer called the asthenosphere, mantle rock melts to make
magma, trapping superheated water under great pressure. As a result, to the northeast of the subducting
edge lies the continuous arc of volcanos stretching from Costa Rica to Guatemala and a belt of
earthquakes that extends farther north, into Mexico.
The northern boundary of the Cocos Plate is the Middle America Trench. The eastern boundary is a
transform fault, the Panama Fracture Zone. The southern boundary is a mid-oceanic ridge, the
Galapagos Rise.[1] The western boundary is another mid-ocean ridge, the East Pacific Rise.
The Cocos and Nazca Plates are the remnants of the former Farallon Plate, which broke up about 23
million years ago. A hotspot under the Galapagos Islands lies along the Galapagos Rise. (see Galapagos
hotspot)
The Rivera Plate north of the Cocos Plate, is thought to have separated from the Cocos Plate 5-10
million years ago. The boundary between the two plates appears to lack a definite transform fault, yet
they are regarded as distinct.
The devastating 1985 Mexico City earthquake was a result of the subduction of the Cocos Plate beneath
the North American Plate.
The Eurasian Plate is a tectonic plate which includes most of the continent of Eurasia (a landmass
consisting of the traditional continents of Europe and Asia), with the notable exceptions of the Indian
subcontinent, the Arabian subcontinent, and the area east of the Chersky Range in East Siberia. It also
includes oceanic crust extending westward to the Mid-Atlantic Ridge and northward to the Gakkel
Ridge.
The easterly side is a boundary with the North American Plate to the north and a boundary with the
Philippine Mobile Belt and the Philippine Sea Plate to the south, and possibly with the Okhotsk Plate
and the Amurian Plate. The southerly side is a boundary with the African Plate to the west, the Arabian
Plate in the middle and the Indo-Australian Plate to the east. The westerly side is a convergent boundary
with the North American Plate forming the northernmost part of the Mid-Atlantic Ridge, which is
straddled by Iceland. The 1973 eruption of Eldfell, the volcano of the Icelandic island Heimaey, caused
by the North American and the Eurasian plates pulling apart, is an example of a constructive plate
boundary.
The India or Indian Plate is a tectonic plate that was originally a part of the ancient continent of
Gondwanaland from which it split off, eventually becoming a major plate. About 50 to 55 million years
ago, it fused with the adjacent Australian Plate. It is today part of the major Indo-Australian Plate, and
includes the subcontinent of India and a portion of the basin under the Indian Ocean.
In the late Cretaceous Period about 90 million years ago, subsequent to the splitting off from
Gondwanaland of conjoined Madagascar and India, the India Plate split from Madagascar. It began
moving north, at about 20 cm/yr (8 in/yr) [1], and began colliding with Asia between 50 and 55 million
years ago, in the Eocene epoch of the Cenozoic Era. During this time, the India Plate covered a distance
of 2,000 to 3,000 km (1,200 to 1,900 mi), and moved faster than any other known plate. In 2007,
German geologists determined that the reason the India Plate moved so quickly is that it is only half as
thick as the other plates which formerly constituted Gondwanaland.[1]
The collision with the Eurasian Plate along the boundary between India and Nepal formed the orogenic
belt that created the Tibetan Plateau and the Himalaya Mountains, as sediment bunched up like earth
before a plow.
The India Plate is currently moving northeast at 5 cm/yr (2 in/yr), while the Eurasian Plate is moving
north at only 2 cm/yr (0.8 in/yr). This is causing the Eurasian Plate to deform, and the India Plate to
compress at a rate of 4 mm/yr (0.15 in/yr).
The Juan de Fuca Plate, named after the explorer, is a tectonic plate arising from the Juan de Fuca
Ridge, and subducting under the northerly portion of the western side of the North American Plate at the
Cascadia subduction zone. It is bounded on the south by the Blanco Fracture Zone, on the north by the
Nootka Fault, and along the west by the Pacific Plate. The Juan de Fuca Plate was originally part of the
once-vast Farallon Plate, now largely subducted under the North American Plate, and has since fractured
into three pieces. The plate name is in some references applied to the entire plate east of the undersea
spreading zone, and in other references only to the central piece. When so distinguished, the piece to the
south is known as the Gorda Plate and the piece to the north is known as the Explorer Plate. The
separate pieces are demarcated by the large offsets of the undersea spreading zone manifested in the
above mentioned fracture zone and fault.
This subducting plate system has formed the volcanic Cascade Range, the Cascade Volcanoes and the
Pacific Ranges, which is part of the Pacific Ring of Fire, along the west coast of North America from
southern British Columbia to northern California.
The last major earthquake at the Cascadia subduction zone was the 1700 Cascadia earthquake, estimated
to have a moment magnitude of 8.7 to 9.2. Based on carbon dating of local tsunami deposits, it occurred
around 1700. As reported in National Geographic on December 8, 2003, Japanese tsunami records
indicate the quake happened the evening of Tuesday, January 26, 1700.
In 2008, small earthquakes were observed within the plate. The unusual quakes were described as "more
than 600 quakes over the past 10 days in a basin 150 miles southwest of Newport." The quakes were
unlike most quakes in that they did not follow the pattern of a large quake, followed by smaller
aftershocks; rather, they were simply a continual deluge of small quakes. Furthermore, they did not
occur on the tectonic plate boundary, but rather in the middle of the plate. The subterranean quakes were
heard on hydrophones, and scientists described the sounds as similar to thunder, and unlike anything
heard previously.[1]
The Nazca Plate, named after the Nazca region of southern Peru, is an oceanic tectonic plate in the
eastern Pacific Ocean basin off the west coast of South America.
The eastern margin is a convergent boundary subduction zone under the South American Plate and the
Andes Mountains, forming the Peru-Chile Trench. The southern side is a divergent boundary with the
Antarctic Plate, the Chile Rise, where seafloor spreading permits magma to rise. The western side is a
divergent boundary with the Pacific Plate, forming the East Pacific Rise. The northern side is a divergent
boundary with the Cocos Plate, the Galapagos Rise. A triple junction occurs at the northwest corner of
the plate where the Nazca, the Cocos, and the Pacific plates all join off the coast of Colombia.
A second junction, the Chile Triple Junction, occurs at the southwest corner at the intersection with the
Nazca, the Pacific, and the Antarctic plates off the coast of southern Chile. At each of these triple
junctions an anomalous microplate exists, the Galapagos Microplate at the northern junction and the
Juan Fernandez Microplate at the southern junction. The Easter Island Microplate is a third microplate
that is located just north of the Juan Fernandez Microplate and lies just west of Easter Island.
Yet another triple junction, the Chile Triple Junction,[1] occurs on the seafloor of the Pacific Ocean off
Taitao and Tres Montes Peninsula at the southern coast of Chile. Here three tectonic plates meet: the
Nazca Plate, the South American Plate, and the Antarctic Plate. This triple junction is unusual in that it
consists of a mid-oceanic ridge, the Chile Rise, being subducted under the South American Plate at the
Peru-Chile Trench. This triple junction has been considered to be related to the moment magnitude 9.5,
1960 megathrust earthquake known as the Great Chilean Earthquake.
Luckily, very few islands are there to suffer the earthquakes that are a result of complicated movements
at these junctions. Juan Fernández Islands is an exception.
The Carnegie Ridge is a 1350-km-long and up to 300-km-wide feature on the ocean floor of the
northern Nazca Plate that includes the Galápagos archipelago at its western end. It is being subducted
under South American with the rest of the Nazca Plate.
The absolute motion of the Nazca Plate has been calibrated at 3.7 cm/yr east motion (88°), some of the
fastest absolute motion of any tectonic plate. The subducting Nazca Plate, which exhibits unusual flatslab subduction, is tearing as well as deforming as it is subducted (Barzangi and Isacks). The subduction
has formed, and continues to form the volcanic Andes Mountain Range. Deformation of the Nazca Plate
even affects the geography of Bolivia, far to the east (Tinker et al.).
The precursor of the Nazca Plate and the Cocos Plate to its north was the Farallon Plate, which split in
late Oligocene times, about 22.8 Mya, a date arrived at by interpreting magnetic anomalies.
The North American Plate is a tectonic plate covering most of North America, Greenland and parts of
Siberia and Iceland. It extends eastward to the Mid-Atlantic Ridge and westward to the Chersky Range
in eastern Siberia. The plate includes both continental and oceanic crust. The interior of the main
continental landmass includes an extensive granitic core called a craton. Along most of the edges of this
craton are fragments of crustal material called terranes, accreted to the craton by tectonic actions over
the long span of geologic time. It is believed that much of North America west of the Rockies is
composed of such terranes.
For the most part, the North American Plate moves in roughly a southwest direction away from the MidAtlantic Ridge.
The motion of the plate cannot be driven by subduction as no part of the North American Plate is being
subducted, except for a very small section comprising part of the Puerto Rico Trench; thus other
mechanisms continue to be investigated.
One recent study suggests that a mantle convective current is propelling the plate. [4]
The easterly side of the North American Plate is a divergent boundary with the Eurasian Plate to the
north and the African Plate to the south forming the northern part of the Mid-Atlantic Ridge.
The southerly boundary with the Cocos Plate to the west and the Caribbean Plate to the east is a
transform fault, represented by the Cayman Trench under the Caribbean Sea and the Motagua Fault
through Guatemala.
The rest of the southerly margin which extends east to the Mid Atlantic Ridge and marks the boundary
between the North American Plate and the South American Plate remains poorly understood and
undefined. The westerly boundary is the Queen Charlotte Fault running offshore along the coast of
Alaska and the Cascadia subduction zone to the north, the San Andreas Fault through California, the
East Pacific Rise in the Gulf of California, and the Middle America Trench to the south.
On the northerly boundary is a continuation of the Mid-Atlantic ridge called the Gakkel Ridge. The rest
of the boundary in the far northwestern part of the plate extends into Siberia. This boundary continues
from the end of the Gakkel Ridge as the Laptev Sea Rift, on to a transitional deformation zone in the
Chersky Range, then the Ulakhan Fault, and finally the Aleutian Trench to the end of the Queen
Charlotte Fault system.
On its western edge the Farallon Plate has been subducting under the North American Plate since the
Jurassic period. The Farallon Plate has almost completely subducted beneath the western portion of the
North American Plate leaving that part of the North American Plate in contact with the Pacific Plate as
the San Andreas Fault. The Juan de Fuca, Cocos, and Nazca Plates are remnants of the Farallon Plate.
The boundary along the Gulf of California has not yet been clearly described and research is ongoing.
The Gulf is underlain by the northern end of the East Pacific Rise. West of the Rise is the Pacific Plate.
East of the Rise, most tectonic maps show the North American Plate.
It is generally accepted that a piece of the North American Plate was broken off and transported north as
the East Pacific Rise propagated northward, creating the Gulf of California. However, it is as yet unclear
whether the oceanic crust east of the Rise and west of the mainland coast of Mexico is actually a new
plate beginning to converge with the North American Plate, consistent with the standard model of rift
zone spreading centers generally.
The Pacific Plate is an oceanic tectonic plate beneath the Pacific Ocean.
To the north the easterly side is a divergent boundary with the Explorer Plate, the Juan de Fuca Plate and
the Gorda Plate forming respectively the Explorer Ridge, the Juan de Fuca Ridge and the Gorda Ridge.
In the middle the easterly side is a transform boundary with the North American Plate along the San
Andreas Fault and a boundary with the Cocos Plate. To the south the easterly side is a divergent
boundary with the Nazca Plate forming the East Pacific Rise.
The southerly side is a divergent boundary with the Antarctic Plate forming the Pacific-Antarctic Ridge.
The westerly side is a convergent boundary subducting under the Eurasian Plate to the north and the
Philippine Plate in the middle forming the Mariana Trench. In the south, the Pacific Plate has a complex
but generally convergent boundary with the Indo-Australian Plate, subducting under it north of New
Zealand forming the Tonga Trench and the Kermadec Trench. The Alpine Fault marks a transform
boundary between the two plates, and further south the Indo-Australian Plate subducts under the Pacific
Plate forming the Puysegur Trench. The part of Zealandia to the east of this boundary is the plate's
largest block of continental crust.
The northerly side is a convergent boundary subducting under the North American Plate forming the
Aleutian Trench and the corresponding Aleutian Islands.
The Pacific Plate contains an interior hot spot forming the Hawaiian Islands.
It is believed that the Pacific Plate is moving in unison with the minor, Bird's Head Plate.
The Philippine Sea Plate is a tectonic plate beneath the Pacific Ocean to the east of the Philippines. The
Philippine Sea Plate comprises oceanic lithosphere that lies beneath the Philippine Sea, and so has been
referred to in the scientific literature of the last 50 years as the Philippine Sea Plate.
Most segments of the Philippines, including northern Luzon, are part of the Philippine Mobile Belt,
which is separate from the Sunda Plate to the southwest, the South China Sea Plate to the west and
north-west, Taiwan to the north, and the Philippine Sea Plate to the east. Although parts of the Republic
of the Philippines, Palawan with the Calamian Islands, plus the Sulu Archipelago with the Zamboanga
Peninsular of western Mindanao, are the tops of two protruding north-eastern arms of the Sunda Plate.
They are in collision with the Philippine Mobile Belt.
The Philippine Sea Plate is demarkated on the west by the Philippine Trench and the East Luzon Trench,
bounded by Taiwan and the Ryukyu islands to the northwest, Japan to the north, the Izu-Ogasawara
(Bonin) and Mariana Islands to the east, and Yap, Palau, and the north-easternmost part of Indonesia,
Halmahera to the south. The eastern part of the plate is occupied by the Izu-Bonin-Mariana Arc system
and bounded by the Mariana Plate.
The easterly side of the Philippine Sea Plate is a convergent boundary with the subducting Pacific Plate.
The Philippine Sea Plate is subducted on the west under the Philippine Mobile Belt, and bounded on the
south by the Caroline Plate and Bird's Head Plate, on the north by the North American Plate (or the
Okhotsk Plate) and possibly by the Amurian Plate.
Subduction of the Philippine Sea Plate under remnants of the Eurasian Plate, plus break-away parts of
the Philippine Sea Plate formed the Philippine Mobile Belt and Taiwan, and induced the volcanic
activity on the eastern side of the Philippine Mobile Belt. This subduction and volcanic activity is
ongoing.
In the northernmost part of the plate, thickened crust of the Izu-Bonin-Mariana arc is colliding with
Japan constituting the Izu Collision Zone.
The Izu Peninsula is the northernmost tip of the Philippine Sea Plate. The Philippine Sea Plate, the
Eurasian Plate (or the Amurian Plate), and the North American (or Okhotsk Plate) meet at Mount Fuji.
The Scotia Plate is an oceanic tectonic plate bordering the South American Plate on the north, the South
Sandwich Plate to the east, and the Antarctic Plate on the south and west.
The north and south boundaries of the plate are transform fault boundaries. At the eastern margin the
Scotia has a spreading boundary between it and the small South Sandwich Plate. The South American
Plate is subducting under east side of the South Sandwich Plate, which is thought to have brought about
its separation from the Scotia Plate, starting as backarc spreading. The western boundary with the
Antarctic plate is a complex and rather ill-defined boundary.
There is some speculation that the westward motion of the South American Plate may have forced the
Caribbean and Scotia Plates at its northern and southern ends respectively to squeeze around it. Both
share a similar shape and are bounded along their eastern side by a subducting part of the South
American Plate. [1]
The South American Plate is a tectonic plate covering the continent of South America and extending
eastward to the Mid-Atlantic Ridge.
The easterly side is a divergent boundary with the African Plate forming the southern part of the MidAtlantic Ridge. The southerly side is a complex boundary with the Antarctic Plate and the Scotia Plate.
The westerly side is a convergent boundary with the subducting Nazca Plate. The northerly side is a
boundary with the Caribbean Plate. At the Chile Triple Junction in Taitato-Tres Montes Peninsula an
oceanic ridge, the Chile Rise, is subducting under the South American plate.
The remains of the Farallon Plate, split into the current Cocos Plate and Nazca Plate are still subducting
under the western edge of the South American Plate. This subduction is responsible for lifting the
massive Andes Mountains and causing the volcanos which are strewn throughout them.
Major plates
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African Plate
Antarctic Plate
Arabian Plate
Australian Plate
Caribbean Plate
Cocos Plate
Eurasian Plate
Indian Plate
Juan de Fuca Plate
Nazca Plate
North American Plate
Pacific Plate
Philippine Sea Plate
Scotia Plate
South American Plate
[edit] Minor plates
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Aegean Sea Plate
Altiplano Plate
Amurian Plate
Anatolian Plate
Apulian Plate
Balmoral Reef Plate
Banda Sea Plate
Bird's Head Plate
Burma Plate
Caroline Plate
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Conway Reef Plate
Easter Plate
Futuna Plate
Galapagos Plate
Halmahera Plate
Hellenic Plate
Iranian Plate
Jan Mayen Plate
Juan Fernandez Plate
Kermadec Plate
Kula Plate
Manus Plate
Maoke Plate
Mariana Plate
Molucca Sea Plate
New Hebrides Plate
Niuafo'ou Plate
North Andes Plate
North Bismarck Plate
Okhotsk Plate
Okinawa Plate
Panama Plate
Philippine Microplate
Rivera Plate
Sangihe Plate
South Sandwich Plate
Shetland Plate
Solomon Sea Plate
Somali Plate
South Bismarck Plate
Sunda Plate
Timor Plate
Tonga Plate
Woodlark Plate
Yangtze Plate
[edit] Plates within orogens
Some models identify more minor plates within current orogens.
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Apulian Plate
Explorer Plate
Gorda Plate
[edit] Ancient plates
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Baltic Plate
Bellingshausen Plate
Charcot Plate
Cimmerian Plate
Farallon Plate
Insular Plate
Intermontane Plate
Izanagi Plate
Lhasa Plate
Moa Plate
Phoenix Plate
http://en.wikipedia.org/wiki/List_of_tectonic_plates
Notes from PowerPoint presentation used to guide lecture/conversation.
Activity/Landforms found at CONVERGENT BOUNDARIES:
When two plates collide (at a convergent plate boundary), some crust is destroyed in the impact and the
plates become smaller. The results differ, depending upon what types of plates are involved.
Oceanic Plate and Continental Plate - When a thin, dense oceanic plate collides with a relatively light,
thick continental plate, the oceanic plate is forced under the continental plate; this phenomenon is called
subduction.
Two Oceanic Plates - When two oceanic plates collide, one may be pushed under the other and magma
from the mantle rises, forming volcanoes in the vicinity.
Two Continental Plates - When two continental plates collide, mountain ranges are created as the
colliding crust is compressed and pushed upwards.
http://www.enchantedlearning.com/subjects/astronomy/planets/earth/Continents.shtml
Activity/Landforms found at DIVERGENT BOUNDARIES:
Seafloor spreading is the movement of two oceanic plates away from each other (at a divergent plate
boundary), which results in the formation of new oceanic crust (from magma that comes from within the
Earth's mantle) along a mid-ocean ridge. Where the oceanic plates are moving away from each other is
called a zone of divergence. Ocean floor spreading was first suggested by Harry Hess and Robert Dietz
in the 1960's.
http://www.enchantedlearning.com/subjects/astronomy/planets/earth/Continents.shtml
In plate tectonics, a divergent boundary or divergent plate boundary (also known as a constructive
boundary or an extensional boundary) is a linear feature that exists between two tectonic plates that
are moving away from each other. These areas can form in the middle of continents but eventually form
ocean basins. Divergent boundaries within continents initially produce rifts which produce rift valleys.
Therefore, most active divergent plate boundaries are between oceanic plates and are often called midoceanic ridges. Divergent boundaries also form Volcanic Islands which occur when the plates move
apart to produce gaps which molten lava rises to fill. Thus creating a shield volcano which would
eventually build up to become a volcanic island.
http://en.wikipedia.org/wiki/Divergent_boundary
Activity/Landforms found at TRANSFORM BOUNDARIES:
Also called “TRANSFORM FAULT, LATERAL SLIPPING, STRIKE SLIP, CONSERVATIVE
PLATE BOUNDARY”
When two plates move sideways against each other (at a transform plate boundary), there is a
tremendous amount of friction which makes the movement jerky. The plates slip, then stick as the
friction and pressure build up to incredible levels. When the pressure is released suddenly, and the plates
suddenly jerk apart, this is an earthquake.
http://www.enchantedlearning.com/subjects/astronomy/planets/earth/Continents.shtml
If this brings up faults…Normal, Reverse, Strike-Slip – PRINT OUT LAB DRAWINGS AND DRAW
ON CHALKBOARD
What is a tectonic plate?
A tectonic plate (also called lithospheric plate) is a massive, irregularly shaped slab of solid rock,
generally composed of both continental and oceanic lithosphere. Plate size can vary greatly, from a few
hundred to thousands of kilometers across; the Pacific and Antarctic Plates are among the largest. Plate
thickness also varies greatly, ranging from less than 15 km for young oceanic lithosphere to about 200
km or more for ancient continental lithosphere (for example, the interior parts of North and South
America).
How do these massive slabs of solid rock float despite their tremendous weight? The answer lies in the
composition of the rocks. Continental crust is composed of granitic rocks which are made up of
relatively lightweight minerals such as quartz and feldspar. By contrast, oceanic crust is composed of
basaltic rocks, which are much denser and heavier. The variations in plate thickness are nature's way of
partly compensating for the imbalance in the weight and density of the two types of crust. Because
continental rocks are much lighter, the crust under the continents is much thicker (as much as 100 km)
whereas the crust under the oceans is generally only about 5 km thick. Like icebergs, only the tips of
which are visible above water, continents have deep "roots" to support their elevations.
http://pubs.usgs.gov/gip/dynamic/tectonic.html
The theory of plate tectonics (meaning "plate structure") was developed in the 1960's. This theory
explains the movement of the Earth's plates (which has since been documented scientifically) and also
explains the cause of earthquakes, volcanoes, oceanic trenches, mountain range formation, and many
other geologic phenomenon. The plates are moving at a speed that has been estimated at 1 to 10 cm per
year. Most of the Earth's seismic activity (volcanoes and earthquakes) occurs at the plate boundaries as
they interact.
The top layer of the Earth's surface is called the crust (it lays on top of the plates). Oceanic crust (the
thin crust under the oceans) is thinner and denser than continental crust. Crust is constantly being
created and destroyed; oceanic crust is more active than continental crust.
Under the crust is the rocky mantle, which is composed of silicon, oxygen, magnesium, iron, aluminum,
and calcium. The upper mantle is rigid and is part of the lithosphere (together with the crust). The lower
mantle flows slowly, at a rate of a few centimeters per year. The asthenosphere is a part of the upper
mantle that exhibits plastic properties. It is located below the lithosphere (the crust and upper mantle),
between about 100 and 250 kilometers deep.
http://www.enchantedlearning.com/subjects/astronomy/planets/earth/Continents.shtml
http://pubs.usgs.gov/gip/dynamic/tectonic.html
ADDITIONAL LESSON PLAN IDEA, COURTESY OF BARBARA SHAW, TAUGHT DURING
GEOSCIENCE FOR ELEMENTARY EDUCATORS, PSU, SPRING 09:
Laboratory Title (9): The Earth’s Plates
Your Name: Lisa McCready
Concepts Addressed: Plate Tectonics; faults
Lab Goals: Students will explore how the Earth’s plates move and cause formations
Lab Objectives:
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Students will visualize plate motions and faulting, using foam model pieces
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Students will describe plate motions and faulting
Benchmark(s) Addressed (4th/5th grade):
4.1 Structure and Function: Living and non-living things can be classified by their characteristics
and properties.
4.1P.1 Describe the properties of forms of energy and how objects vary in the extent to which they
absorb, reflect, and conduct energy.
4.1E.1 Identify properties, uses, and availability of Earth materials.
4.2 Interaction and Change: Living and non-living things undergo changes that involve force and
energy.
4.2P.1 Describe physical changes in matter and explain how they occur.
4.2L.1 Describe the interactions of organisms and the environment where they live.
4.2E.1 Compare and contrast the changes in the surface of Earth that are due to slow and rapid
processes.
4.3 Scientific Inquiry: Scientific inquiry is a process of investigation through questioning, collecting,
describing, and examining evidence to explain natural phenomena and artifacts.
4.3S.3 Explain that scientific claims about the natural world use evidence that can be confirmed and
support a logical argument.
5.2 Interaction and Change: Force, energy, matter, and organisms interact within living and nonliving systems.
5.2P.1 Describe how friction, gravity, and magnetic forces affect objects on or near Earth.
Materials and Costs:
List the equipment and non-consumable material and estimated cost of each
Metric ruler (1 per group, groups of 3, 10 groups, .79 x 10) .................................$7.90
Estimated total, one-time, start-up cost: ................................................................$7.90
List the consumable supplies and estimated cost for presenting to a class of 30 students
Foam-Open cell (12 pieces=29.81) ......................................................................$59.62
Felt pens (2 per group, 1.15 x 20) ........................................................................$23.00
Manila folders/Thin poster board (box of 100)....................................................$11.99
Rubber cement (1.99 each) ..................................................................................$19.90
Foam-Closed cell (12 pieces=29.81) ...................................................................$59.62
Pins (500 for 5.79) .................................................................................................$5.79
Styrofoam core poster board, 0.6cm/1/4” thick (3.90 for 25 sheets) .....................$7.80
Razor blade knife (6.29 each) ..............................................................................$62.90
Paper (Quiz, .01 x 30, printed on front and back-2 page quiz) ..............................$0.30
Estimated total, one-time, start-up cost: ............................................................$258.82
Time:
Initial Preparation time: 60 – 120 minutes (buying supplies)
Preparation time: 10 -15 minutes (getting supplies together before lesson)
Instruction time: 30 – 60 minutes
Clean-up time: 10 minutes
Assessment (include all assessment materials):
QUIZ – 30 copies printed before lesson
1. Sketch a normal fault.
2. Sketch a reverse fault.
3. Sketch a strike-slip fault.
4. Name the 3 plate tectonic boundaries types discussed in class and provide an example of what
happens at these boundaries.
5. True or False: There are only plates below the continents.
Math Time!!! (HOORAY!!!)
Saturn Data:
Diameter
Mass
Rotation on Axis
Metric
120,536 km
5.6846×1026 kg
10h 47m
British
37,448.80 miles
1.2532x1022 pound
10 hours 47 minutes
Note:
Scientific notation: 1x1012 = 1,000,000,000,000 or 1e+12 = 1,000,000,000,000
http://www.bbc.co.uk/schools/ks3bitesize/maths/shape_and_space/images/circle_1.gif
Formulas:
Surface Area of a Sphere:
SA = 4r 2
Velocity:
v = d/t
Volume:
V = (4/3) r3
r = ½ Diameter
Circumference =  Diameter
Abbreviations:
  = (pi) 3.14
(circumference/diameter)
  = change ( = end - begin)
 D = density
 d = distance
 m = mass
 r = radius (derived from diameter)
 SA = Surface Area
 t = time
 v = velocity
 vol = volume
What is the surface area of Saturn?
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r = ½ 120,536km or 60,268km
SA =
4r 2
4 (3.14 (60268km2))
45620831709.44km2
What is the velocity of Saturn?
To derive distance traveled, we follow one spot on Saturn’s equator as it travels all the way
around and back to the beginning. That is the circumference.
 Circumference = 3.14(120,536km) or 378,483.04 (to verify, the actual circumference is
380,887km – but remember that our calculation is for a perfect sphere, and Saturn experiences
the greatest oblation, so the actual is larger that the calculated.
 ( = ending – beginning, so d = 378,483 – 0, and t = 10 hours 47 min. – 0. then, we need
to find the fractional hour in 47 minutes, or 47/60 = 0.7833)
=
d/t
378,483km/10.7833hr
35,099.0 km/hour
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v
What is the volume of Saturn?
V= (4/3) r3
(4/3) (3.14) (60,268km3)
916,491,866,031,820km3
Now, let’s figure out those same questions for Earth, but this time, you do it by yourself!
Earth Data:
Metric
Diameter
Mass
Rotation on Axis
Your Calculations Here:
What is the surface area of Earth?
What is the velocity of Earth?
What is the volume of Earth?
12,750 km
5.9736×1024
23h 56min 4.09s
Teaching About Plate
Tectonics and Faulting Using
Foam Models
L.W. Braile,
Professor
Purdue University
(braile@purdue.edu)
http://web.ics.purdue.edu/~braile
September, 2000
http://web.ics.purdue.edu/~braile/edumod/foammod/foammod.htm
Objective: Demonstrate plate tectonic principles, plate boundary interactions and the geometry and
relative motions of faulting of geologic layers using 3-D foam models. The foam models aid in visualization
and understanding of plate motions and faulting because the models are three-dimensional, concrete rather
than abstract descriptions or diagrams, can be manipulated by the instructor and the students, and the models
can show the motions of the plates and faults through time in addition to the three-dimensional configuration
of the plates or layers. The fault and plate boundary models shown here illustrate relatively simple motions
and geologic structures. Although these models are accurate representations of real Earth faulting and plate
tectonic structures and motions, the spherical shape of the Earth and the complexity of geological features
caused by varying rock types and rock properties and geological development over many millions or
hundreds of millions of years, result in significant complexity and variability of actual fault systems and
plate tectonic boundaries.
Materials:
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Foam (open cell, foam mattress type) “blocks” shown in Figure 1A
Felt pens (permanent marker, red and black)
Manila folders or thin poster board
Rubber cement
Closed cell foam (“sleeping bag pads,” camping equipment) as shown in Figures 3 and 5
Pins
Open cell foam as shown in Figure 3A
Styrofoam core poster board, 0.6 cm (1/4 in) thick, as shown in Figure 3B
Razor blade knife
Metric ruler
Procedure:
Faulting and Plate Boundaries
1. Prepare foam block models as shown in Figure 1A. The cardboard (cut from manila folders or thin
poster board) attached to both faces of the fault plane allows the blocks to slip easily along the fault
as forces are applied to the blocks. Use the block models to demonstrate extensional (normal)
faulting as the two outer blocks are moved apart as shown in Figure 1B. This procedure is best
performed by holding the blocks “in the air” in front of you, supporting the model by the two outer
blocks, rather than on a table. Note that as the two outer blocks are moved apart, the inner block
drops downward or “subsides.” This relationship between extensional motion of geologic layers and
downdropped fault blocks (graben or rift valley if the downdropped block is bounded on both sides
by normal faults, as in this block model) produces normal faulting (Figure 2) and also represents the
extensional motion and resultant rift development associated with divergent plate boundaries (Table
1). Examples of divergent plate boundaries, where extensional faulting is prominent, are the midocean ridge system in which a narrow rift or graben (downdropped fault block) is commonly
observed along the highest part of the ridge (see section 2 below) and the East African Rift in which
extension has been occurring in the continental lithosphere for about 30 million years and the
resulting rift system of normal faults is beginning to break apart the continent. In a plate-tectonicrelated, but not plate boundary environment, the Basin and Range area of the Western United States
displays a prominent topographic signature of extensional faulting with many adjacent downdropped
fault blocks or grabens (the topographic “high” areas between the grabens are called horsts; see IRIS
poster on western US seismicity and topography).
To demonstrate compressional motion and resulting reverse (also called thrust) faults (Figure 2), hold
the foam block models as described above and then move the two outer blocks together as in Figure
1C. The inner block will be thrust upwards producing reverse faults and an uplifted block. In a plate
tectonic setting, such compressional motion is associated with convergent plate boundaries (Table 1)
where two lithospheric plates are moving together or colliding (see also section 3 below). Not
surprisingly, these convergent zones are associated with mountain ranges (Himalayas, Alps, Andes,
Cascades, etc.).
To demonstrate horizontal slip or strike-slip fault motion, prepare foam blocks as shown in Figure
1D. Moving the blocks horizontally on a tabletop, as shown in Figure 1E, demonstrates strike-slip
(Figure 2) or horizontal slip fault motion. This motion along a plate boundary is also called
transform (Table 1). The San Andreas fault zone is a system of strike-slip faults which form the
transform plate boundary at the western edge of the North American Plate. Transform faults also
occur as oceanic fracture zones between segments of the mid-ocean ridge spreading zones (see ocean
bathymetry map in a world atlas, such as the National Geographic World Atlas, or view ocean
bathymetry on the Internet at:
http://www.ngdc.noaa.gov/mgg/announcements/images_predict.HTML; click on one of the regions
containing a mid-ocean ridge to see details of ridge crest and transform fault topography of the ocean
floor).
2. Divergent Plate Boundary and Sea Floor Spreading  Prepare the foam pieces that represent the
oceanic lithosphere at a spreading center (mid-ocean ridge divergent plate boundary) as shown in
Figure 3A. Cut 10 one cm by 20 cm strips of the closed-cell foam material. Color half of the strips
black with the felt pen and label all of the foam pieces as shown in Figure 3A. Construct a “ridge”
(optional) to form the base for the sea floor spreading model. The ridge surface represents the top of
the asthenosphere in the upper mantle and the foam layer above the base is the oceanic lithosphere typically about 50-100 km thick in the Earth. The base also provides a mid-ocean ridge topography
in which the spreading and extension occurs along the narrow rift zone along the ridge crest.
To demonstrate the concepts of a divergent plate boundary and mid-ocean ridge spreading centers,
begin by placing the two 20 x 20 cm foam pieces on the base (Figure 3B) with one edge adjoined at
the ridge crest and the arrows on the foam pieces pointing outward (Figure 3A). These squares will
represent oceanic lithosphere at a time five million years ago and thus contain oceanic crust (the
upper layer of the lithosphere) that is 5 million years old and older. Slide the two foam squares away
from each other about 2 cm (this process represents the passage of time and the extension of the
lithosphere in the region of the ridge crest, and rift valley, by plate tectonic motions which are
typically a few centimeters per year, equivalent to a few tens of km per million years) and place the
two strips labeled 4 million years in the space that is created. Attach one strip to each edge of the
squares using pins. In the real mid-ocean ridge, a void space or opening between the plates created
by the spreading process, would not actually develop. Instead, as extension occurs, volcanic and
igneous intrusion processes will relatively continuously fill in the extended lithosphere, in the process
creating new lithosphere. Because the oceanic crustal layer in this new lithosphere is formed from
igneous (volcanic and intrusive) processes, it cools from a liquid and the rocks acquire a remanent
magnetic direction that is consistent with the Earth’s magnetic field direction at that time. Because
the Earth’s magnetic field occasionally reverses its polarity (north and south magnetic poles switch),
the lithosphere created at mid-ocean ridges displays “stripes” of normal and reversed magnetic
polarity crust approximately parallel to the ridge crest. Additional information on these magnetic
stripes and mid-ocean ridge processes can be found in “This Dynamic Earth”. The igneous rocks
which are formed at the ridge crest can also be “dated” using radiometric dating of rock samples to
determine the age of the volcanism and intrusion.
Continue to extend the two plates away from each other at the ridge crest and add the new pieces of
lithosphere (attach with pins) which are labeled in decreasing age (3, 2, 1 and 0 million years old).
When you are finished, the mid-ocean ridge divergent plate boundary and adjacent lithosphere should
look like the diagram shown in Figure 3A and represent a modern (zero million years old) mid-ocean
ridge spreading center. Note that the youngest rocks are in the center, along the ridge crest, and the
rocks are progressively older (to 4 million years old in the strips and 5 million years old and older in
the lithosphere represented by the squares of foam) away from the ridge crest.
3. Convergent Plate Boundary and Subduction  Arrange two tables of identical height to be next to
each other and about 30 cm apart as shown in Figure 4. Place the two pieces of one-inch thick foam
on the tables and begin to move one piece of foam (the one without the cardboard edge) toward the
other and allow it to be “thrust” beneath the other piece of foam. The foam pieces represent two
lithospheric plates. As the convergence continues, the underthrust plate will form a subducted slab of
lithosphere (extending to at least 600 km into the mantle in the Earth) as shown in Figure 4.
Earthquakes commonly occur along the length of the subducted slab and compressional structures
(folds and faults) are often associated with the compressional zone near the colliding plates. The
subducted lithosphere consists of relatively low-melting-point rocks (sediments and oceanic crust
form the upper layers of the oceanic lithosphere) which can melt at depths of 100-150 km as the slab
is subducted into the mantle. These molten materials can then ascend through the overlying mantle
and crust and form volcanoes which are often situated in a linear chain or arc about 100-200 km away
from the collision zone. A deep ocean trench also forms above the point of convergence of the two
plates as the oceanic lithosphere is bent downwards by the collision.
4. Transform or Strike-Slip Plate Boundaries and Elastic Rebound  Use a razor-blade knife to make the
foam “plate” models shown in Figure 5. The foam is 1.25 cm (1/2”) thick closed-cell foam often
used for “sleeping pads” for camping. It is available at camping supply stores and Wal-Mart and
Target. The foam pieces can be used on a table top or on an overhead projector (the slits cut in the
foam allow the 10 cm long tabs which bend to be seen projected onto a screen). By continuously
sliding the two plates past each other with the “tab” edges touching (Figure 5), the foam pieces
represent lithospheric plates and the “zone” where the plates touch is a strike-slip (transform) fault.
Note that as the plates move slowly with respect to each other (just as Earth’s lithospheric plates
move at speeds of centimeters per year), the area of the plates adjacent to the fault (the tabs) becomes
progressively bent (deformed), storing elastic energy. As the process continues, some parts of the
fault zone will “slip” releasing some of the stored elastic energy. This slip occurs when the stored
elastic energy (bending of the tabs) results in a force along the fault which exceeds the frictional
strength of the tabs that are in contact. Sometimes, only small segments of the fault zone (one or two
tabs) will slip, representing a small earthquake. At other times, a larger segment of the fault will slip,
representing a larger earthquake. Note that although the plate motions are slow and continuous, the
slip along the fault is rapid (in the Earth, taking place in a fraction of a second to a few seconds) and
discontinuous. The motions and processes illustrated by the foam model effectively demonstrates the
processes which occur in actual fault zones and the concept of the elastic rebound theory (Bolt,
1993). A brief segment during the beginning of the video “Earthquake Country” illustrates a similar
“stick-slip” motion using a model made of rubber strips.
Extensions, Connections, Enrichment:
1. Good preparatory lessons for these activities are studies of elasticity (a spring and masses can be
used to demonstrate the two fundamental characteristics of elasticity - the stretching is
proportional to the force (suspended mass) and the existence of the “restoring force” (elastic
energy is stored) in that the spring returns to its original length as the force (mass) is removed),
and seismic waves which are generated as the fault slips.
2. The stick-slip process is well illustrated in a segment of the NOVA video “Killer Quake” in
which USGS geophysicist Dr. Ross Stein demonstrates this process using a brick which is pulled
over a rough surface (sandpaper) using an elastic cord (bungy cord). An experiment using this
same procedure is described in “Seismic Sleuths” (AGU/FEMA).
3. Additional information on plate tectonics is available in Bolt (1993), Ernst (1991), Simkin et al.
(1994), the TASA CD “Plate Tectonics,” “This Dynamic Earth,” and nearly any secondary school
or college level geology textbook. Elastic rebound is well illustrated in Lutgens and Tarbuck
(1996), Bolt (1993) and the TASA CD. A color map of the Earth’s plates is available on the
Internet at: http://www.geo.arizona.edu/saso/Education/Plates. An excellent description of plate
tectonics can be found at: http://pubs.usgs.gov/publications/text/understanding.html.
4. An additional plate tectonic activity is the EPIcenter lesson plan “Voyage Through Time - A Plate
Tectonics Flip Book” in which continental drift during the past 190 million years - a consequence
of plate tectonics - is effectively illustrated; and Plate Puzzle which uses the "This Dynamic
Planet" map.
5. Additional plate tectonic activities, especially for younger students, are contained in “Tremor
Troop” (NSTA/FEMA).
6. A leading theory explaining why the Earth’s plates move is convection currents in the Earth’s
mantle. The interior structure of the Earth is described in Bolt (1993) and is the subject of the
EPIcenter activity “Earth’s Interior Structure.” Good activities illustrating convection are
contained in the GEMs guide “Convection - A Current Event” (Gould, 1988), or “Tremor Troop”
(NSTA/FEMA).
References:
Bolt, B.A., Earthquakes and Geological Discovery, Scientific American Library, W.H. Freeman, New York, 229 pp., 1993.
Braile, L.W., “Earth’s Interior Structure” - http://web.ics.purdue.edu/~braile/educindex/educindex.htm.
Braile, L.W. and S.J. Braile, “Voyage Through Time - A Plate Tectonics Flip Book” http://web.ics.purdue.edu/~braile/educindex/educindex.htm.
Braile, L.W. and S.J. Braile, "Plate Puzzle" – http://web.ics.purdue.edu/~braile/educindex/educindex.htm.
Ernst, W.G., The Dynamic Planet, Columbia University Press, New York, 281 pp., 1990.
FEMA/AGU, Seismic Sleuths - Earthquakes - A Teachers Package on Earthquakes for Grades 7-12, American Geophysical
Union, Washington, D.C., 367 pp., 1994. (FEMA 253, for free copy, write on school letterhead to: FEMA, PO Box
70274, Washington, DC 20024).
Gould, A., Convection - A Current Event, GEMS, Lawrence Hall of Science, Berkeley, California, 47 pp., 1998.
IRIS, Western US Seismicity and Topography Poster, www.iris.edu.
Lutgens, F.K., and E.J. Tarbuck, Foundations of Earth Science, Prentice-Hall, Upper Saddle River, New Jersey, 482 pp., 1996.
NSTA/FEMA, Tremor Troop - Earthquakes: A teacher’s package for K-6 grades, NSTA Publications, Washington, DC, 169 pp.,
1990. (This book contains a reasonably complete curriculum for teaching earthquake and related Earth science topics;
FEMA 159, for free copy, write on school letterhead to: FEMA, PO Box 70274, Wash., DC 20024).
Simkin et al., This Dynamic Planet, map, USGS, 1:30,000,000 scale ($7 + $5 shipping), 1994, also at:
http://pubs.usgs.gov/pdf/planet.html; 1-888-ASK-USGS.
TASA “Plate Tectonics” CD-Rom - Plate tectonics, earthquakes, faults, ($59 or $155 for site license), (800-293-2725)
http://www.tasagraphicarts.com, Mac or Windows.
U.S. Geological Survey, This Dynamic Earth: The Story of Plate Tectonics, available from: U.S. Geological Survey, Map
Distribution, Federal Center, PO Box 25286, Denver, CO 80225, $6, (800 USA MAPS). Also available (full text and
figures) for viewing at: http://pubs.usgs.gov/publications/text/dynamic.html.
Videos (NOVA “Killer Quake,” and “Earthquake Country”) - information available in “Seismology-Resources for Teachers”
online at:
http://web.ics.purdue.edu/~braile/edumod/seisres/seisresweb.htm.
Figure 1. Foam (soft, open cell foam used for mattresses) blocks for demonstrating faults (normal, reverse and strikeslip) and motions at plate boundaries (divergent and extensional motion; convergent and compressional motion;
transform and horizontal slip motion). Large arrows show direction of force or plate motion. Half-arrows along faults
show direction of relative motion along the fault plane. Shaded area is red felt pen reference line. A. Foam block
with 45 angle cuts (cardboard, cut from manila folders, attached to angled faces with rubber cement) and reference
line drawn on the side of the blocks with a felt pen. B. Response of model to extension. C. Response of model to
compression. D. Foam blocks used to demonstrate strike-slip motion. Cardboard is attached to the two faces (as
shown in Figure) using rubber cement. Reference lines and arrows are drawn on the top of the foam blocks using a felt
pen. E. Response of model to horizontal slip motion.
Figure 2. Block diagrams illustrating types of geological faults with resulting offsets of layers. Half-arrows show
relative motion of the blocks along the fault plane.
Figure 3. Foam pieces for demonstrating divergent plate boundaries and a mid-ocean ridge spreading center. Cut out
pieces with razor blade knife and straight-edge. A. Top view of foam blocks after assembly (see text) representing 5
million years of extension at the ridge crest and generation of new lithosphere by magmatic (igneous) processes.
Numbers are ages in millions of years. In the real Earth, the time periods of normal (shaded) and reversed polarity
would not be of equal duration (one million years in this simulation) and thus the ‘stripes” would be of varying
widths. B. Side view showing foam pieces on top of styrofoam base (two pieces, each 20 cm x 30 cm) which creates
slopes representing the mid-ocean ridge. Attach styrofoam with pins to foam piece (2 cm x 20 cm) used to create
slope.
Figure 4. Foam (soft, open cell foam) pieces (each piece is 50 cm by 15 cm by 2.5 cm (1 in) thick) used to
demonstrate convergent plate motions and subduction. Edge of one of the foam pieces is cut at a 45 angle and lined
with cardboard (manila folder material), using rubber cement to attach the cardboard to the foam.
Figure 5.
Foam pieces used to demonstrate strike-slip faulting, elastic rebound theory, and slipping along the fault
plane during earthquakes. Cut out slits with razor blade knife and straight-edge.
Table 1. Faults, Plate Boundaries and Relative Motions*
Relative
Motion of
Layers or
Plates
Fault
Names
Extension
Normal
Divergent (extensional, moving
apart, spreading, construction because new lithosphere is
generated in the extended zone)
Rifts, grabens, sometimes
volcanism, regional uplift but
local downdropped fault
blocks, shallow earthquakes
Compression
Reverse or
Thrust
Convergent (compressional,
collision, subduction, moving
together, destructive - because
one plate is often thrust into the
mantle beneath the other plate)
Folded mountain ranges, uplift,
reverse faults, volcanic arcs
(usually andesitic composite
volcanoes), deep ocean
trenches, shallow and deep
earthquakes in subducted slab
Translation
or horizontal
slip
Strike-slip
Transform (horizontal slip,
translation)
Linear topographic features,
offset stream channels, lakes in
eroded fault zone, pull-apart
basins and local uplifts along
fault bends or “steps” between
offset fault segments, oceanic
fracture zones, offsets of midocean ridges
Plate Boundary
Descriptions
Related Tectonic and
Geologic Features
*Many terms and geological “jargon” are associated with faults and plate boundaries. While these terms are
useful to Earth scientists and are included here and in the accompanying text for completeness, the most
important concepts such as extension, moving apart, downdropped blocks, etc., can be discussed and
understood without unnecessary jargon. Additional information on the terms and concepts used here can be
found in virtually any introductory geology textbook or in the USGS booklet “This Dynamic Earth - The
Story of Plate Tectonics.”
Copyright
2000. L. Braile. Permission granted for reproduction for non-commercial uses.
ADDITIONAL LESSON PLAN IDEA, COURTESY OF AN ONLINE SEARCH FOR
CONTINENTAL PLATES LESSON PLANS:
http://jclahr.com/science/earth_science/cr06/workshop/activities/snack/snack_tectonics.html
Snack Tectonics
Students use graham crackers and frosting to learn about the different aspects of plate
tectonics. They manipulate the graham crackers in various ways to model divergent plate
boundaries, convergent plate boundaries - continental and oceanic, convergent plate
boundaries - continental, and lateral plate boundaries. Students observe what happens to the
graham crackers and frosting and discuss their findings.
Below is a description of the activity from http://www.mbmg.mtech.edu/kids/shakin.htm
A crack in the earth's crust is called a fault. The large
crack where two huge earth plates move against each
other is a fault line. Fault lines are where the action
happens.
What you'll need:
Graham crackers
Waxed paper spread with a thick layer of frosting or
peanut butter.
Milk (To drink with the crackers after finishing the
experiments.)
Put two graham crackers
Whose fault is this?
side by side, and slide one
up away from you and the
What if you went outside after an earthquake and found
other one down toward
the raspberries your family planted in the front yard
you.
were growing in front of your next door neighbor's
house ( and in your yard were
When plates move past
the roses from the next
each other like this, things house)? This is what happened
don't exactly go smoothly. in San Francisco along one of
In fact, the plates usually get stuck on each other and
the most famous fault lines in
then give a lurch and move on, sending waves of
the world— the San Andreas
vibrations through the earth's interior (much like the
Fault in California, a 600 -mile
circular waves that ripple out when you drop a pebble in
boundary where the American
the water). These vibrations are so powerful the we have and Pacific Plates meet. In
a special name for them— earthquake!
1906, there was an earthquake
along this fault line and the
earth moved about 20 feet in
less than a minute! Wonder who got to eat the ripe
berries?
Put two graham crackers
very close to each other
on the wax paper and
slowly push them
together.
These two delicious and fun projects and many
more can be found in GEOLOGY ROCKS!, a
You've made a rift, or big
Williamson Publishing book by Cindy Blombaum crack in the ocean floor. As the plates separate, magma
oozes up from below and makes new ocean floor or
creates underwater mountain ranges.
Push two crackers toward
each other, make one slide
underneath the other.
When this happens on
earth, watch out! The
bottom plate starts to melt
from the intense heat and pressure. It becomes new
magma that floats up between two plates, building up and
up over many years until it finally causes a volcano blast!
That plate action caused Mt. St. Helens in Washington
State to blow its top!
Put two graham
crackers side by side
on the wax paper (wet
the edge of one graham
cracker in milk first),
and slowly push them
together.
The ridge of pushed -up
cracker is just like many mountain ranges around the
earth that were formed as two plates slowly crumbled
together over millions of years. The Himalayas ( the
mountain range that includes Mount Everest) were
formed when India crashed into Asia.
A similar, but more complete, lesson is given in Windows to the Universe. The materials needed are:
For each student:
One large graham crackers broken in half (i.e., two square graham crackers)
Two 3-inch squares (approx.) of fruit roll up
Cup of water
Frosting
About one square foot of wax paper with a large dollop of frosting. ( Instruct students to spread frosting
into a layer about half a cm thick.)
Plastic knife or spoon
Activity:
http://www.windows.ucar.edu/tour/link=/teacher_resources/teach_snacktectonics.html
Directions overheads:
http://www.windows.ucar.edu/tour/link=/teacher_resources/snack_tect_overheads.html
ADDITIONAL LESSON PLAN IDEA, COURTESY OF AN ONLINE SEARCH FOR
CONTINENTAL PLATES LESSON PLANS:
“Egg Plates”
http://www.pbs.org/wgbh/aso/tryit/tectonics/
The following are my additional ideas but they are not laid out in the traditional lesson
plan format because I did not have time for that much detail before submitting my
lesson plan!
1. Have a game at the end of the unit for the kids to show all of the wonderful knowledge they have
learned. I would use many questions from the following website:
http://www.learner.org/interactives/dynamicearth/testskills.html
And incorporate my own questions based on what was presented.
The game could be played like Jeopardy, with the students in groups who work together on
answering the questions.
2. Assign each student/pair of students a specific plate. They can do many things with this:
a. Create a poster
i. Geography
ii. Geology
iii. Climate
iv. Biomes
v. Direction the plates are moving
vi. Plates it will eventually collide with
vii. Fun facts
viii. Etc.
b. Create a report with the same information
c. Create a simple oral presentation
d. Create an in depth presentation
3. Do a lesson where they dive deep into the mathematics of the plates. Give them the direction the
plates are moving and the speeds/velocity. They can work through a set of math problems to calculate
when certain plates will collide or certain oceans will open up, etc.!
4. Use Google Earth to locate some of the boundaries and look at the ocean bottoms!