1. Volcanoes
Mr. Silva

2. Vocabulary

3. Vocabulary
• Volcano-

4. Vocabulary
• Volcano-
– Lava and pyroclastoc material built up on the
earth’s surface around a vent.

5. Vocabulary
• Volcano-
– Lava and pyroclastoc material built up on the
earth’s surface around a vent.
• Volcanism-

6. Vocabulary
• Volcano-
– Lava and pyroclastoc material built up on the
earth’s surface around a vent.
• Volcanism-
– Any activity that includes the movement of
magma toward or onto the earth’s surface.

7. Vocabulary
• Volcano-
– Lava and pyroclastoc material built up on the
earth’s surface around a vent.
• Volcanism-
– Any activity that includes the movement of
magma toward or onto the earth’s surface.
• Vent-

8. Vocabulary
• Volcano-
– Lava and pyroclastoc material built up on the
earth’s surface around a vent.
• Volcanism-
– Any activity that includes the movement of
magma toward or onto the earth’s surface.
• Vent-
– Opening through which molten rock flows onto
the earth’s surface.

9. Vocabulary
• Magma-
– Liquid rock produced deep inside the earth
• Lava-
– Magma that reaches the earth’s surface
• Fissures-
– Cracks through which lava flows
• Hot Spots-
– Areas of volcanism within plates

10. Notes

11. Notes
1. Most of the asthenosphere remains solid,
because of the great pressure of the
surrounding rock

12. Notes
1. Most of the asthenosphere remains solid,
because of the great pressure of the
surrounding rock

13. Notes
1. Most of the asthenosphere remains solid,
because of the great pressure of the
surrounding rock
i. Magma forms when mantle material flows to
areas of lower pressure, or when fluids such as
water are added

14. Notes

15. Notes
2. Volcanism involves any activity that includes
the movement of magma toward or onto the
Earth’s surface

16. Notes
2. Volcanism involves any activity that includes
the movement of magma toward or onto the
Earth’s surface

17. Notes
2. Volcanism involves any activity that includes
the movement of magma toward or onto the
Earth’s surface
a. Lava is magma that erupts onto the Earth’s surface

18. Notes
2. Volcanism involves any activity that includes
the movement of magma toward or onto the
Earth’s surface
a. Lava is magma that erupts onto the Earth’s surface
i. Vent- the opening that molten rock flows
through to reach the surface

19. Notes
2. Volcanism involves any activity that includes
the movement of magma toward or onto the
Earth’s surface
a. Lava is magma that erupts onto the Earth’s surface
i. Vent- the opening that molten rock flows
through to reach the surface
ii. Volcano- the structure formed by the vent and
volcanic material that builds up around the vent

20. Notes Con’t

21. Notes Con’t
3. Major Volcanic Zones

22. Notes Con’t
3. Major Volcanic Zones
a. Subduction Zones

23. Notes Con’t
3. Major Volcanic Zones
a. Subduction Zones
i. When an oceanic and a continental plate meet,
the oceanic plate, the oceanic plate subducts,
because it is more dense

24. Notes Con’t
3. Major Volcanic Zones
a. Subduction Zones
i. When an oceanic and a continental plate meet,
the oceanic plate, the oceanic plate subducts,
because it is more dense
ii. The subducted plate dives deep into the
asthenosphere, causing water to combine with
nearby mantle material

25. Notes Con’t
3. Major Volcanic Zones
a. Subduction Zones
i. When an oceanic and a continental plate meet,
the oceanic plate, the oceanic plate subducts,
because it is more dense
ii. The subducted plate dives deep into the
asthenosphere, causing water to combine with
nearby mantle material
iii. This forms magma

26. Notes Con’t
3. Major Volcanic Zones
a. Subduction Zones
i. When an oceanic and a continental plate meet,
the oceanic plate, the oceanic plate subducts,
because it is more dense
ii. The subducted plate dives deep into the
asthenosphere, causing water to combine with
nearby mantle material
iii. This forms magma
iv. Some magma erupts through the Earth’s surface
forming:

27. Notes Con’t
3. Major Volcanic Zones
a. Subduction Zones
i. When an oceanic and a continental plate meet,
the oceanic plate, the oceanic plate subducts,
because it is more dense
ii. The subducted plate dives deep into the
asthenosphere, causing water to combine with
nearby mantle material
iii. This forms magma
iv. Some magma erupts through the Earth’s surface
forming:
1. Volcanic mountains- where a continental plate
collides with an oceanic plate

28. Notes Con’t
3. Major Volcanic Zones
a. Subduction Zones
i. When an oceanic and a continental plate meet,
the oceanic plate, the oceanic plate subducts,
because it is more dense
ii. The subducted plate dives deep into the
asthenosphere, causing water to combine with
nearby mantle material
iii. This forms magma
iv. Some magma erupts through the Earth’s surface
forming:
1. Volcanic mountains- where a continental plate
collides with an oceanic plate
2. Island arcs- where two oceanic plates collide

29. Notes

30. Notes
b. Mid-Ocean Ridges

31. Notes
b. Mid-Ocean Ridges
i. As the plates pull apart, magma wells up
along the rift zone
1. The magma adds new lithosphere to the ridge

32. Notes
b. Mid-Ocean Ridges
i. As the plates pull apart, magma wells up
along the rift zone
1. The magma adds new lithosphere to the ridge

33. Notes
b. Mid-Ocean Ridges
i. As the plates pull apart, magma wells up
along the rift zone
1. The magma adds new lithosphere to the ridge
c. Hot Spots

34. Notes
b. Mid-Ocean Ridges
i. As the plates pull apart, magma wells up
along the rift zone
1. The magma adds new lithosphere to the ridge
c. Hot Spots
i. Volcanoes that do not form at plate
boundaries

35. Notes
b. Mid-Ocean Ridges
i. As the plates pull apart, magma wells up
along the rift zone
1. The magma adds new lithosphere to the ridge
c. Hot Spots
i. Volcanoes that do not form at plate
boundaries
ii. Hot spot is beneath the lithospheric plate,
and the plate moves over it