1. Supervolcanoes and calderas !

2. The Volcanic Explosivity Index- how big is a supereruption ? VEI- 5 Plinian, Mt St Helens VEI 3 Vulcanian Montserrat VEI 1 Hawaiian

3. VEI 6 Ultra-plinian Mt Pinnatubo

4. VEI 8 Imagine 100 Pinnatubos erupting at the same time

5. Supervolcanoes and calderas ! Caldera - created from large, explosive eruptions of felsic pyroclastic material. The caldera is created when the roof of the magma chamber collapses. Can be 10’s km’s across Different from a crater E.g., Yellowstone, WY, 1 m.y.

6. Huge caldera, so big it could only be seen from space

7. http://youtube.com/watch?v=Abg5-gLdEb0 Supervolcano !

8. Why are supervolcano eruptions so big ? A) There is a higher % of gas in the magma B) The collapsing magma chamber roof helps the eruption C) The magma is more viscous D) A large volume of magma was ready to erupt E) Eruptions occur simultaneously from a ring of vents. http://www.cotf.edu/ete/movies/caldera.mov

9. Which type of volcano would you rather live beside and why? Cinder cone Stratocolcano(composite) Sheild volcano Supervolcano with caldera