1. Monday Starting Line
Directions: Answer on the Google Form found in Planbook.
What is the Pacific Ring of Fire?
Based on the evidence we have and the location of different volcanoes and earthquakes, what must be located near the Pacific Ring of Fire?
At which 2 types of plates boundaries do volcanoes form?

2. Monday Starting Line
Directions: Answer on the Google Form found in Planbook.
A zone of many active volcanoes and earthquakes located near the Pacific Ocean
Plate Boundaries
Convergent (subduction zones), divergent (mid-ocean ridges)

3. Announcements Homework Turn-In: Pacific Ring of Fire Lab (Turn-in)
You will be receiving a take home test tomorrow. It will be Due next Tuesday November 29.

4. Notebook Notes
Directions: In your document, write the following information in this order on the LEFT SIDE.
(Your Name)
Mr. Swisher
Earth and Space Science _____ (Period)
11/21/2016

5. Notebook Notes
Directions: In your document, write the following information in this order in the CENTER in BOLD.
13.2 Volcanic Eruptions

6. Lava vs. Magma Lava = ON the surface of the Earth
Magma = UNDER the surface of the Earth
Forms from melted crust and mantle

7. Two Types of Magma There are two main types of magma: Mafic magma:
Rich in magnesium and iron
Color = Dark
Found in oceanic crust
Felsic magma:
Rich in feldspars and silica
Color = Light
Found in continental crust

8. Two Types of Eruptions There are two main types of eruptions:
Quiet Eruptions:
From mafic magma
Magma flows out quietly
Low viscosity: thin, flows out quickly
Happens often on the ocean floors (out of mid-ocean ridges)
Explosive Eruptions:
From felsic magma
Magma shoots out of the volcano with pyroclastic material
High viscosity: thick; flows out slowly

9. Lava Flow As lava flows out of a volcano, it cools in different ways.
Mafic lava cools quickly and can form 3 types of lava flows:
Pahoehoe: Cooled, wrinkled lava
Aa: Cooled, jagged lava
Blocky lava: Cooled, chunky lava

10. Lava Flow

11. Pyroclastic Material
During explosive eruptions with felsic magma, ash and other rock fragments called pyroclastic material fly out of the volcano.
There are 5 types of pyroclastic material:
Volcanic dust: Very small rocks (.25 mm)
Volcanic ash: Small rocks (2 mm)
Lapilli: Larger rocks (“little stones,” 64 mm)
Volcanic blocks: Even larger rocks
Volcanic bombs: Largest rocks

12. Pyroclastic Material

13. Types of Volcanoes There are 3 types of volcanoes: Shield Volcanoes
Have a broad base with gently sloping sides
Form quiet eruptions with mafic magma
Example: Hawaiian Islands (U.S.)
Composite Volcanoes
Have layers of lava flows and pyroclastic material
Form quiet AND explosive eruptions
Example: Mount St. Helens (U.S.)
Cinder Cones
Have very steep slopes, but are SMALL
Form explosive eruptions with pyroclastic material

14. Volcano Pictures
Cinder Cone
Shield
Composite

15. Status of Volcanoes There are 3 different statuses of volcanoes:
Active Volcanoes
Is erupting or shows signs that it will erupt in the near future (has erupted in 10,000 years or less)
Example: Mount St. Helen’s (U.S.)
Dormant Volcanoes
Is not active now, but may become active in the future
Example: Mount Raineir (U.S)
Extinct Volcanoes
Is unlikely to erupt again (hasn’t erupted in 10,000 years or more)
Example: Kilimanjaro (Tanzania)

17. Caldera
When the magma chamber of a volcano empties, a large depression called a caldera is left behind.
Can later fill with water to make a lake!

18. Caldera

19. Causes of Eruptions Volcanoes erupt when…
pressure is released when tectonic plates move.
Example: Earthquake
the density of the magma decreases (as the temperature increases) & magma rises up the central vent.

20. Types of Volcanoes Worksheet