plate tectonics study guide answers

PLATE TECTONICS STUDY GUIDE ANSWERS

1. List the Layers of the Earth in order from the interior out

Inner coreOuter core

Mantle Crust

4 Main Layers

2. Temperature and Pressure both ___________ with depth

Increases

3. How do scientists study the interior of the Earth?

Seismic Waves.

4. What makes up the inner core and outer core?

Iron and Nickel

*Mostly IRON*Outer Core=liquid

5. What 3 types of evidence did Alfred Wegener use to support his theory of Continental Drift

1. Geological: Mountains in S. America line up with those in Africa

2. Fossils: Glossopteris and dinosaur remains in certain areas

3. Climate: Glaciers in Africa and tropical plants in Antarctica

Fit of Continents Across the

Atlantic

Mountain ranges in South

America line up exactly with

those in Africa!

Notice how fossils lined up across continents! http://evolution.berkeley.edu/evolibrary/images/history/fossils3.gif

Did you know... 1. that India was once in the Southern Hemisphere connected to Antarctica? 2. that North America was once surrounded by warm, tropical seas? 3. that Africa was once covered by glaciers, which were kilometers in thickness? 4. that the Sahara desert was once a tropical rain forest?

6. What is Pangea?

The supercontinent of all continents as one landmass

7. What is a fossil

Remains of living things. Has to have rapid burial and

be preserved

8. What is the mid-ocean Ridge

The longest chain of mountains in the world.

Found at the bottom of the Atlantic Ocean. Formed at a divergent boundary where

molter material is coming up from the mantle

Did you know that the Earth’s longest mountain range is underwater and is called the mid-ocean ridge?

: www.ocean.udel.edu

The Mid-Ocean Ridge system, shown above snaking its way between the continents, is more than 56,000 kilometers (35,000 mi)

long. It circles the earth like the stitching on a baseball!

9. Explain the process of sea-floor spreading and where does it take

place?Sea-floor happens at a divergent

boundary at the mid-ocean ridge. New crust is being made and getting pushed further from

the boundary. Old crust=further away from

boundary

Convection Currents

10. The movment of the plates is caused by_____________

1. Plate Tectonics=plates are in constant motion due to convection currents.

2. Continental drift=all continents were once a single land mass named Pangea

11. Explain the Theory of Plate Tectonics and Continental Drift

1. Covergent: collide/coming together. Produces: Mountains, trenches, volancoes, volcanic islands

2. Divergent: apart. Produces: rift valleys and mid-ocean ridges

3. Transform: slide horizontally. Produces: earthquakes and faults

12. List and describe the 3 types of boundaries

Diverge on continental plates

13. A rift valley forms where two plates do what?

Continental crust diverging from continental

Made up of the upper mantle and crust. It is the tectonic plates that are moving on top of the

asthenosphere

14. What is the lithosphere?

The plastic like layer that is found in the upper mantle.

The plates float on this!

15. What is the asthenosphere?

Convection=transfer of heat. It happens in the

mantle because the molten material is getting heated

from the inner core.Hot=less dense=rises

Cold=more dense=sinks

16. Explain convection currents in the mantle.

Mid-ocean ridges *Sea floor spreading

17. Where is new ocean crust created?

This is a model of sea floor spreading at a divergent boundary is called a

mid ocean ridge.

1. C + C=mountains 2. C + O= subduction of O.

Volcanoes and trenches form.

3. O + O=subdction of one of the O’s. Volcanic islands and trenches form

18. Explain the three different kinds of convergent boundaries

Inner core.

*The liquid outer core makes the inner core spin

19. Earth’s Magnetic Field results from the spinning of the ___________

Ocean crust is being formed at divergent boundaries.

20. Why is ocean crust younger than continental crust

The ocean crust is being subducted back into the mantle causing a trench

21. What happens at trenches on the ocean floor?

Density = mass/volume!

22. What is density?

Divergent

23. What type of boundaries form at mid-ocean ridges?

Asthenosphere

24. Which layer do the Earth’s plates float on?

It’s MORE DENSE. Twice as much elements!!!

25. Explain why oceanic crust is subducted at an oceanic-

continental boundary.