1. Volcanoes

2. What are volcanoes?
A volcano is a conical hill or mountain formed by material from the mantle being forced through an opening or vent in the Earth's crust.

3. How do they Form Result of eruption at a hot spot
Develop on boundaries of moving plates

4. Where are they Found

5. Why do volcanoes erupt? There is too much pressure where the magma is
The gases than explode violently
Thus it creates an explosions

6. Main Features

7. States of a Volcano
Active
Likely to erupt again

8. States of a Volcano
Dormant
Has not erupted in 2000 years

9. States of a Volcano
Extinct
Will never erupt again

10. Types of Volcanoes
Shield volcanoes
Flat
Found in Hawaii

11. Types of Volcanoes
Composite volcanoes
Tall and thin
Mount Fuji

12. Types of Volcanoes
Cinder cones
Made of loose volcanic fragments

13. Disadvantages When volcanoes erupt, it will kill many people
The ash generated will hinder agriculture

14. Disadvantages
Dropping of global temperatures

15. Advantages Minerals from the ash makes the soil fertile
Clean energy resource (geothermal energy)

16. Advantages
Tourist attraction

17. Historical Eruptions Mt. st. Helen Destroyed its northen flank
Flattened million of Douglas Fir trees

18. Historical Eruptions Krakatoa Killed 36000 people
Created ash falls and tsunamis

19. Facts
The word “volcano” was derived from the roman god of fire, Vulcan.
More than 80% of earth’s surface is volcanic in origin
Half of the 500 volcanoes in the world are found in the “Ring of Fire ”

20. References http://volcanoes.usgs.gov/ash/agric/index.html

21. The End!
I hope you have enjoyed it!