Answer the questions using the information in the following Web site:
1. Look at the diagram to see the different types of hazards.
Click on Gas to go to that page.
2. Define fumarole.
3. Why do yellow crystals form around the vent?
4. Explain why gas bubbles form as magma rises.
5. Explain why gases make eruptions explosive.
6. Explain why volcanic gases are hazards to humans.
Click on Vog to go to that page
7. Which gas causes vog in Hawaii?
8. How does vog affect humans?
Return to Gas page.
9. How can human tell that H2S is released by volcanoes?
10. Discuss the formation of lava haze (see Secondary Gas Emissions).
11. Explain why lava haze is acidic.
Click on Lahars to go to that page
12. Describe a lahar.
13. What are some of the other terms for lahars?
14. What causes lahars?
15. Are lahars common in Hawaii?
Click on Landslides to go to that page
16. Discuss the factors that lead to the generation of volcano landslides.
Click on Lava Flows to go to that page
17. Which factors affect the speed of a lava flow?
18. Give the range of speeds for lava flows.
19. Why is death from lava flows uncommon?
Click on Pyroclastic Flows
20. Define pyroclastic flow.
21. How fast do pyroclastic flows move?
22. How hot are pyroclastic flows?
Click on Tephra to go to that page
23. Which type of volcanic hazard is the most widespread?
24. Why is volcanic ash a hazard?