1. Explain why some parts of the world are mountainous, others are flat and still others are covered by oceans.
2. Describe what you know about plate tectonics.
1. How many major plates cover Earth’s surface? How wide are some of them?
2. How thick are the plates, on average? Is this thick or thin, compared with the rest of Earth’s layers?
3. What is the name of the Earth layer above which tectonic plates move? How hot is this layer beneath the plates?
4. What is Earth’s core like? Describe both its outer and inner regions.
5. Explain what convection is and why it’s responsible for the movement of Earth’s rock. Be sure to include the terms upwelling and sinking in your explanation.
6. About how fast are plates moving, on average?
7. What are Pangaea, Laurasia and Gondwanaland?
8. The story compares the recently discovered jelly layer beneath the plates with grease. But what is this jelly layer really?
9. Explain how scientists discovered Earth’s “jelly” layer.
10. What’s one explanation for what caused the partial melt layer?
11. What is a chemical signature, and how did one help scientists confirm that Earth’s rock cycles from the inside out?
12. New data indicate that tectonic plates have been moving across Earth’s surface for how long?
13. Describe three ways that plates interact with each as their edges meet.
1. Were you surprised to read that the term “continental drift” is inaccurate? Explain why or why not.
2. Based on what you learned from the story, draw a map of how you think Earth might look 300 million years from now. How might the plates — and the continents atop them — be different from today?
1. Do you think people should build — or not build — cities based on the local risk of volcanic and earthquake hazards? Explain your answer.
2. Map the regions of Earth above the edges of tectonic plates. What are the biggest cities near those edges? What types of risks might they face? (Consider, for instance, the Sumatra quake and some impacts from quakes there.) How might communities prepare for any movement of the plates near them? Explain your answers.