1. Science Starter: THUR WEEK 5
Last night there was an 8.3 magnitude earthquake that struck in Illapel, Chile South America. What was the most likely cause of this earthquake?
A. the movement of the Nazca Plate and S. American plate along a transform boundary
B. the subduction of the Nazca Plate under the S. American Plate
C. The spreading of the Nazca Plate from the S. American Plate
D. The subduction of the S. American Plate under the Nazca Plate

2. ESSAY QUESTION
At their highest point , nearly 320 million years ago, the Appalachian mountains were higher than Mt. Everest. Today, Mt. Everest is about 23,000 ft. higher than the Appalachians and is still growing. Both mountain ranges were formed by the collision of two tectonic plates. Explain two reasons why the Appalachians are getting smaller.

3. Inside the Earth What does the inside of Earth look like? Layers
How are the layers arranged?
By density
What happens to the temperature and pressure as you travel into the center of Earth?
Both Increase

4. Inside the Earth How do we know so much about Earth’s Interior?
Seismic waves from earthquakes
Seismic waves travel at different speeds and directions as they pass through the different layers of Earth.

5. Restless Continents True or False: The continents are always moving?
What is this called?
Continental drift
Who created the theory of continental drift?
Alfred Wegener

6. Restless Continents What discovery helped prove Wegener’s theory?
Mid-ocean ridges
How did we discover mid-ocean ridges?
Better Technology/sonar

7. Restless Continents
What process happens at mid-ocean ridges to help move Earth’s plates?
Sea-floor Spreading

8. What is the proof of sea-floor spreading?
1. Age of the sea-floor
The sea-floor is older as you move farther from a mid-ocean ridge
2. Magnetic stripes on the sea-floor

9. The Theory of Plate Tectonics
The theory that Earth’s lithosphere are divided into _______ that move around on top of the ______.
Plates, asthenosphere

10. The Theory of Plate Tectonics
What is the main cause of plate movement?
Convection currents
How do convection currents work?
Core heats up molten rock making it less dense. The molten rock rises up towards the crust, where it cools down. As it cools it gets more dense and begins to sink back down through the mantle. This cycle will repeat over time, gradually moving Earth’s plates.
Flash Presentation

11. The Theory of Plate Tectonics
Two plates moving away from each other = ______
Divergent boundary
Two oceanic plates are spreading apart =________
Mid-ocean Ridge/Sea-floor spreading
Two continental plates diverging =________
Rift Valley

12. The Theory of Plate Tectonics
Two plates colliding with each other = _______
Convergent Boundary
Two continental plates colliding = ________
Mountains
Oceanic plate and Continental plate colliding=_____
Trenches, mountains, and volcanoes

13. The Theory of Plate Tectonics
At convergent boundary between a continental plate and an oceanic plate what process will happen?
Subduction
Why?
The oceanic plate is more dense, so it goes under the continental plate.

14. The Theory of Plate Tectonics
What type of boundary forms when two plates slip or slide past each other?
Transform Boundary
What disaster can be associated with transform boundaries?
Earthquakes