1. VOLCANOES Stromboli Volcano B. Chouet Kanaga Volcano, Alaska Kanaga Volcano, Alaska E. Klett

2. WHERE DO VOLCANOES FORM?  Diverging Plate Boundaries  Convergent (subduction) Boundaries  Hot spots

3. VOLCANOES AROUND THE WORLD Press & Siever

4. RING OF FIRE

5. VOLCANO TYPES  Shield  Cinder  Composite Kamoali'i Cinder Cone Haleakala National Park, HI National Park Service

6. VOLCANO TYPES Volcanoes are classified by two things: - type of material that forms the - type of material that forms the volcano(lava, tephra, or both) volcano(lava, tephra, or both) - type of eruption it has (quiet or explosive) explosive)

7. TEPHRA (Pyroclastic Material) Solid particles blasted out during an explosive volcanic eruption including –Ash: fine-grained dust –Cinder: <4 mm (scoria) –Bombs: rounded fragments >4 mm –Blocks: angular fragments >4 mm Celestian

8. 3 Types of volcanoes  Shield – largest  Cinder Cone – smallest  Composite

9. Shield Volcano Not very steep; fast moving lava flows; basaltic Press & Siever

10. Mauna Kea & Mauna Loa Shield Volcanoes atlas.geo.cornell.edu/.../ shield_volcanoes.html atlas.geo.cornell.edu/.../ shield_volcanoes.html

11. Cinder Cone Composed of layers of tephra; steep-sided; Press & Siever

12. Sunset Crater, Arizona Cinder cones are small and only erupt once Tarbuck & Lutgens

13. Paracutin, Mexico 1943-1952 1943-1952 Cinder cone rose out of a corn field Cinder cone rose out of a corn field www.raphaelk.co.uk/ main/worldwonders.htm www.raphaelk.co.uk/ main/worldwonders.htm www.mexconnect.com/

14. Composite (Strato) Volcano Alternating layers of lava and tephra; explosive; viscous, slow moving lava Press & Siever

15. Mt Fuji, Japan Composite Cone Composite Cone Pearson Prentice Hall

16. Mt. St. Helens - Composite cone before May 18, 1980 eruption Press & Siever

17. Mt. St. Helens - 1980 Press & Siever

18. Mt. St. Helens – after 1980 eruption Press & Siever

20. CALDERA Crater Lake, Oregon  Collapsed volcanic crater  After eruption, magma chamber collapses Dusty Davis

21. CALDERA Press & Siever

22. FLOOD BASALTS  fast flowing lava (low viscosity)  Basaltic lava  Large volume Press & Siever

23. Columbia River Basalts Press & Siever

24. Columbia Flood Basalts  Rapidly flowing lava  1 mile thickness  Repeated events Press & Siever

25. Basaltic Fissure Eruption Basalt flows near Idaho Falls Tarbuck & Lutgens

26. Laki Fissure, Iceland Erupted in 1783 and killed 1/5 th of the population Press & Siever

27. Hot Spots – Hawaii Magma rises in the middle of a plate.