The Inner Earth

1. By comparison with its average density, what do the densities of water and the Earth's crust tell us about the interior?

2. Describe the Earth's magnetosphere, and describe how it was discovered.

3. How does the Earth's magnetosphere protect us from the harsh conditions in interplanetary space?

4. How do geologists use earthquakes to map the Earth's interior?

5. Compare and contrast P-waves and S-waves, and explain how they are useful in geology.

6. Give two reasons for thinking the Earth's core is liquid.

7. What does differentiation tell us about the Earth's history?

8. How does convection affect the interior of the Earth?

9. How does radioactivity allow us to estimate the age of the Earth?

10. How did radioactive decay heat the Earth early in its history, and when did this heating end?

11. What process is responsible for the large-scale features on the Earth's surface (mountains, oceanic trenches, and so forth)?

12. What conditions are needed for there to be a dynamo in the core of the Earth, and what does this dynamo produce?

13. How do we know that the Earth's magnetic field has reversed in the past, and what effect do you think these reversals may have had on life?