Plate Tectonics

1. How have geologists learned about Earth’s inner structure?
2. How is Earth’s interior like an apple? 
   
3. What are the layers of the Earth?
4. What are the characteristics of Earth’s crust, mantle, and core?
5. How is heat transferred?
6. What causes convection currents?
7. What causes convection currents in Earth’s mantle?
8. What was Alfred Wegener’s hypothesis about the continents?
9. What evidence supported Wegener’s hypothesis?
10. Why was Wegener’s hypothesis rejected by most scientists of his day?
11. How does sea-floor spreading provide a way for continents to move?
12. What is the evidence for sea-floor spreading?
13. What happens at deep-ocean trenches and why?
14. What is the Mid-Atlantic Ridge?
15. What is the theory of plate tectonics?
16. What are the three types of plate boundaries and what are their characteristics?