1. Down to Earth

2. The Restless Planet

3. Earth's Interior

4. The Sea Floor

5. The Birth of a Theory

6. Plate Dynamics

7. Mountain Building

8. Earth's Structures

9. Earthquakes

10. Geologic Time

11. Evolution Through Time

12. Minerals: The Materials of Earth

13. Volcanism

14. Intrusive Igneous Rocks

15. Weathering and Soils

16. Mass Wasting

17. Sedimentary Rocks: The Key to Past Environments

18. Metamorphic Rocks

19. Running Water I: Rivers, Erosion and Deposition

20. Running Water II: Landscape Evolution

21. Groundwater

22. Wind, Dust and Deserts

23. Glaciers

24. Waves, Beaches and Coasts

25. Living With Earth, Part I

26. Living With Earth, Part II

Episode 13. Volcanism

Why does magma rise to the surface?

Where are most of the world's active volcanoes?

What is pillow lava?

Describe the Hawaiian hotspot.

Describe basaltic (mafic) magma and why it commonly forms shield volcanoes.

What are rift zones?

Why are the volcanoes around the Pacific Rim called composite volcanoes?

What common gasses occur in composite (intermediate) magmas?

What factors influence the explosiveness of volcanoes?

Discuss andesitic (intermediate) magmas associated with composite volcanoes.

Describe pumice and how it is formed.

Discuss viscosity and how it relates to the formation of pahoehoe and aa lavas.

How do lava tubes form?

Describe cinder cones and how they differ from composite and shield volcanoes.

What tectonic settings are most volcanoes associated with?

What is obsidian and how is it formed?

Discuss the clues that volcanologists use to predict eruptions.

Discuss how volcanoes relate to ore deposits and geothermal energy.

What are some of the beneficial aspects of volcanoes?

Download the PDF version here