1. The Earth’s Structure

2. The Earth’s Lithosphere

3. S and P Waves S and P waves travel at different speeds Both waves travel through sold material Only P waves can travel through liquids Seismology is the study of vibrations in the Earth What causes vibrations?

4. Seismic Data

5. Seismology Earthquakes cause waves inside Earth Seismology allows us to study the interior of the Earth The speed of the waves depends on the both the density and temperature of the mantle and the core

6. Earth’s Interior Seismic data can be interpreted to find the Density and temperature of the Earth’s interior The metal core is denser as predicted by differentiation Why is the inner core solid? Pressure!

7. Molten Iron Core Iron is a good conductor The Earth’s spin creates eddies in the liquid outer core The iron in the outer core can produce magnetic fields

8. Magnetosphere

9. The Earth’s Crust

10. Plate Tectonics

11. Seismic Activity

12. Continental Drift

13. Continents a Long Time Ago

14. Tectonic Effects on Geography

16. California: On the Edge

17. Earth’s Atmosphere

18. Oxygen and Ozone

19. Carbonate-Silicate Cycle

20. Ocean Balances Climate

21. Ice Ages End

22. Upsetting the Balance

23. Global Warming

24. Depletion of Ozone

25. How the Moon Formed Best theory involves a catastrophic collision Fission, accretion, and capture theories all have weaknesses Figure depicts fission, accretion, and capture theories