Name_____________________________ J#______
Plate Tectonics Webquest (Review)
SITE: Puzzles of the Earth
http://library.thinkquest.org/17701/high/index.html
Go to Earth Structures to start your tour of the world of plate tectonics! Click the puzzle piece at the
bottom of each page to navigate your way through the world of plate tectonics.
1. What are the three main parts of the earth? Give a brief description for each and draw a picture.
Crust—Outermost layer
of the earth
Mantle—Molten Rock
(80% of earth’s
structure)
Core—Innermost layer of
the earth
-Heat source of Mantle
Responsible for driving convection
currents, and ultimately responsible
for plate movement.
* You KNOW there are 4, what are they?
Crust, Mantle, Outer Core, Inner Core
Here are some features (layers within Crust and Mantle:
*Lithosphere = Crust and the upper rigid layer of the mantle
*Asthenosphere = Below the lithosphere—The part of the mantle
that starts to become more liquefied—like Taffy or play-doh-Continents/lithosphere move on top of this
2. The plates that make up the crust fit together like pieces of a
Puzzle
3. Which plate do we live on? North
American (Hint: Earth Map)
4. We live on the earth’s outermost layer. What is it called?
Crust
5. Match each description using a C for continental plates or O for oceanic plates.
O Crust that "carries" the ocean
C Crust that "carries" the continents; may also contain oceans
C Less dense and tends not to subduct. *What does subduct mean? Sink
O More dense and tends to be subducted.
6. How do plates move? Write a description using the terms magma, plates, and convection
currents. COMPARE to a lava lamp!
Tectonic Plates (pieces of the lithosphere) float on molten rock
(magma). Near the core, magma in the mantle is heated, which
causes convection (transfer of heat through liquids) in the magma
(in the mantle). Currents rise and fall due to density (less dense
rises and spreads, which cools and then falls because it is more
dense.) This pushes against the lithosphere and moves the crust;
creating crunching and pulling across the globe!
If you’ve ever watched a lava lamp, you’ve seen
convection currents at work.
1. Heat (from the light bulb) warms up a colored
liquid/wax at the base of the lamp.
2. The colored liquid rises, because hot liquids are less
dense than cool ones.
3. As the blobs of hot liquid move away from the heat
source, they cool off, become more dense again, and
sink back to the bottom. This cycle of movement is
called a convection current.
7. What happens at a convergent boundary? Explain and draw a diagram! *There are 3 types of
convergent boundaries.
2 Plates collide- crust destroyed
8. What happens in each situation?
Continental plate meets oceanic plate –subduction
(one sinks under the other)trench and then beyond the trench lies continental volcanic arcs
Two continental plates meet –mountains
uplift
Two oceanic plates meet – Subduction-trench
and then beyond the trench
lies volcanic island arcs
9. What happens at a divergent boundary? Explain and draw a diagram!
2 plates moving away from each other *there are 2 types
of divergent boundaries (oceanic-oceanic and continentalcontinental)
10. What is sea-floor spreading?
New crust forms where two plates move
away from each other **Oceanic-Oceanic Divergent Boundaries.
11. Describe transform plate movement. Explain and draw a diagram!
earthquake
Friction/
12. What are three geographic features that may be found at plate boundaries? Mountain
Volcano
Trench
SITE: ZOOM Plate Tectonics
http://www.enchantedlearning.com/subjects/astronomy/planets/earth/Continents.shtml
1. Who first proposed the idea of continental drift?
Alfred Wegener
2. What did he name the gigantic supercontinent that existed 200 million years ago? Pangaea
3. When did it begin to break up? Jurassic Period
4. What were the names of the two smaller supercontinents created by the break up?
Gondwanaland and Lauraisa
5. How fast are the plates moving? 1 to10 cm per year
Try the Plate Tectonics Quiz
http://www.enchantedlearning.com/subjects/astronomy/activities/radiobuttonquiz/Tectonicspz.shtml