1. Mountain Building, Volcanoes, and Earthquakes

2. Bellwork – 3-17 What theory is the cartoon at right making fun of?
Name the type of plate boundary and what may form there: A B
What is a subduction zone? What kind of boundary do they form at.
What is the theory of sea floor spreading
What is the theory of plate tectonics?
What causes the plates to move

3. Notes Exit Quiz – answer on an index card
Why wasn’t the theory of continental drift widely accepted?
What theory says that the lithosphere is divided into 7 plates that are moving?
What is a plate boundary?
What forms at subduction zones?
Draw a transverse boundary and describe what might form there
What do scientists call the area around the pacific ocean with a lot of volcanic and seismic activity?

4. EQ: How do mountains form?
SC.7.E.6.5 & 6.7
Describe what forces cause mountain building, and how it is related to plate tectonics.

5. How can plate tectonic motion cause deformation?
Plate movement causes stress on rock structures.
Deformation – when a rock changes shape due to stress. – (great pressure and heat)
It causes rock layers to Bend or Break under stress
Rocks all start out as layers deposited on top of each other over time.
Bending
Breaking
forms folds
Forms faults

6. What are 2 kinds of folds?
Anticlines
Synclines

7. 1. Synclines Youngest layers are found at the core of a fold (center)
older layers are on the outside of the fold
Appear arched inward like a bowl
Youngest rocks
oldest rocks

8. 2. Anticlines The oldest layers are found at core (middle)
Youngest layers are found on the outside of the fold
Look arched upward they are high in the middle
oldest rocks
Youngest rocks

9. Where are the synclines and anticlines?

10. What are faults?
Fault –forms when large blocks of rock break and move past each other
Fault plane – where the 2 fault blocks meet
Footwall – the block under the fault plane
Hanging wall – the block above the fault plane

11. What are the types of Mountains?
The movement of material and heat in Earth’s interior moves the plates that cause Mountain Building
The plates are always in motion so mts are always forming.
They can form through folding, volcanoes, faulting, and uplifting (when the land rises or mountains form)

13. Name the kind of plate movement and the mountains formed

14. What are the 3 types of mountains?
Type of mt
Folded
Volcanic
Fault block
How formed
Type of boundary they form at
Picture
example

15. When you are done: complete the mountains notes sheet and Mountain illustrations – p. 185
Folded Mountains
Fault Block Mountains
Uplifted mountains
Volcanic mountains

16. Volcanoes

17. – T/F Lava is inside earths crust and may contain trapped gases
Volcanoes can form at divergent plate boundaries
A subduction zone is formed at transform boundaries
Dormant volcanoes will never erupt
Volcanoes can only form at plate boundaries

18. Volcanoes EQ: How do volcanoes change the Earth’s Surface?
Describe formation of volcanoes, eruptions, and how they change the earth’s surface.

19. What is a volcano?
Volcano: any place where gas, ash, or melted rock come out of the ground.
Can be a mountain or a crack in the ground
Can be on land or under water

20. What is a volcano?
Volcanoes form as rock below the surface melts and becomes magma
The warm magma rises to surface and becomes lava.
Lava and clouds of gas (ash clouds) erupt from an opening called a vent

21. Label the parts of the volcano
Magma, lava, vent, ash cloud

22. What are kinds of volcanic formations
Fissures and lava plateaus – when lava flows from cracks in the earth’s surface forming a solid layer

23. Crater – an opening or depression at the top of a volcano caused by eruptions

24. Caldera – When the magma chamber empties below a volcano and it collapses leaving a basin shaped depression

25. Where do volcanoes form

26. Volcanoes at divergent boundaries
Plates move away from each other
Create fissure eruptions and shield volcanoes
Ex/ mid ocean ridge and rift valleys

27. Volcanoes at convergent boundaries
Plates move toward each other at subduction zones
Form composite volcanoes and calderas as magma rises and erupts
Cascade Mt Range
(west coast of US)

28. Volcanoes at Hot Spots
They happen in the middle of a plate when a mantle plume rises to the lithosphere
Forms chains of volcanic mountains
Hawaiian islands

29. Volcanic mountains – classified based on shape and eruption style

31. Shield Volcano Mauna Kea volcano gentle slopes
non explosive slow flowing lava eruptions
many times larger than a composite or cinder cone volcano.
Mauna Kea volcano
picture from

33. Cinder Cone - Paracútin
Steep sided, small volcano
Form from Explosive eruptions –
lava contains pyroclastic materials – cinders and bits of rock.
On February 20, 1943, a Mexican farmer noticed that a hole in his cornfield that had been there for as long as he could remember was giving off smoke.
Throughout the night, hot glowing cinders were thrown high into the air.
In just a few days, a cinder cone several hundred meters high covered his cornfield.

35. Composite Volcano – Mount St. Helens
Large volcano with steep sides
Alternating mild eruptions and explosive eruptions
alternating layers of lava and hot ash and bits of rock
Erupted in 1980
57 fatalities
Over 7000 big game animals perished
4 billion board feet of timber (enough to build about 300,000 two-bedroom homes) destroyed
Destroyed 27 bridges, nearly 200 homes. Blast and lahars destroyed more than 185 miles of highways and roads and 15 miles of railways.

37. Turn and talk
What kind of damage and environmental changes might have been caused by the eruption of Mt. St. Helens.

38. 57 fatalities
Over 7000 big game animals perished
4 billion board feet of timber (enough to build about 300,000 two-bedroom homes) destroyed
Destroyed 27 bridges, nearly 200 homes. Blast and lahars destroyed more than 185 miles of highways and roads and 15 miles of railways.

39. Where do volcanoes form?
Volcanoes can form at Plate Boundaries or in the middle of a tectonic plate
Ring of Fire: an area in the pacific ocean with a lot of volcanic activity and earthquakes.

40. Exit: t/f The of volcano shown is a shield volcano
Volcanoes can only form on plate boundaries
Hot spots are located on tectonic plate boundaries.
Cinder cone volcanoes are the largest
All volcanoes form mountains

41. Summary Questions What kind of volcano is shown in the picture below?
Which kind of volcano might have alternating violent and non violent eruptions
What is a hot spot volcano? How is it different from other volcanoes?
What volcanic landform might form at divergent plate boundaries
What volcanic landform forms at hot spots
What volcanic landform forms at convergent plate boundaries?