1. Do now How are volcanoes and earthquakes related?
Can you name some famous volcanoes or areas of the world where there was a big eruption?

2. Earthquakes vs. volcanoes
Earthquakes caused by the movement of plates against each other.
Volcanoes caused by the movement of magma

3. Where?
Volcanoes also form along the tectonic plate boundaries and at hot spots.

4. Magma- Less Dense
Iceland

5. Volcanoes also form along convergent plate boundaries
Volcanic Mountain Ranges
Volcanic Island Arcs

6. Mt vesuvius-italy
Pompeii

7. Hot spots

8. Famous hot spot volcano
Mauna loa
Famous hot spot volcano

9. Vent Parts of a volcano Crater Pipe Magma Chamber Lava Flow
Ash, Dust, Rock
Lava Flow
Vent
Pipe
Rock and Ash Lavers
Magma Chamber

10. Do now Where do volcanoes occur?
Name examples for each area where volcanoes occur.

11. Types of eruptions Why are some eruptions quiet and others explosive?
Trapped Gases
Magma Composition

12. Trapped gases
Water vapor and carbon dioxide trapped in magma build up.
Less pressure as the magma rises.
Quiet eruption- Gas escapes easily from magma
Explosive eruption-Gas builds to high pressures

13. Types of magma- Low amounts of Silica Quiet Eruptions-Magma is fluid
Examples-Hots spots (Hawaii) and divergent boundaries (Iceland)
High amounts of Silica
Explosive Eruptions-Magma is thick
Examples-Mt. St Helens (Washington State)

14. Mauna Loa- Hawaii-QUIET Mt. St. Helens- Washington State-EXPLOSIVE
Explosive vs quiet
Mauna Loa- Hawaii-QUIET
Mt. St. Helens- Washington State-EXPLOSIVE

15. Forms of volcanoes
Shield
Cinder Cone
Composite
Depends on whether the volcano is Quiet or Explosive

16. Shield volcano Broad volcanoes with gently sloping sides
Low silica magma
Quiet Eruptions
Mauna Loa-Hawaiian Islands

17. Cinder cone volcano
-Steep volcanoes build up by ash that settles on the slopes
-High Silica Magma
-Explosive Eruptions
-Paricutin-Mexico

18. Composite volcano
Tall, conical volcanoes formed by different layers of ash, lava, dust and rock
High silica magma
Quiet and explosive eruptions
Mt Vesuvius-Italy
Mt St. Helens

19. Do now
What are the three types of volcanoes and name an example of each?

20. Volcanic rock features
Igneous rock= cooling of lava and magma
Batholith=magma cools underground. Does not erupt.

21. -Cooled magma exposed by erosion
batholiths
-Cooled magma exposed by erosion

22. Dikes and sills Sills-Magma cooled along horizontal cracks in the rock
Dikes-Magma cooled along vertical cracks in the rock
Sills-Magma cooled along horizontal cracks in the rock

23. Necks and caldera Neck-Hardened magma within a volcanic vent.
Caldera-Volcano collapses onto itself.