Download Types of Volcanoes

8.2 Notes
Types of Volcanoes
Key Concept: Tectonic Plate
Motions can result in volcanic
activity at plate boundaries

Which boundary has explosive volcanoes?
Why?

Which boundary has nonexplosive (quiet runny
lava) volcanoes? Why?
What is the difference between magma and
lava?
 Lava is magma once it reaches Earth’s surface

4 types of lava:
1. Aa
2. Pahoehoe
3. Pillow lava
4. Blocky lava
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There are 3 types of Volcanoes
Shield volcano
 Cinder cone volcano
 Composite volcano

Shield Volcanoes
Usually form at hot spots
 Form from many layers of nonexplosive
eruptions (quiet flows of lava)
 The lava is very runny, so it spreads over a
wide area
 Gently sloping sides – not steep
 Very large (meaning wide – not tall)

Cinder Cone Volcanoes
Smallest type of volcano
 Most common type of volcano
 Made of pyroclastic material
 Moderately explosive eruptions
 Steep sides
 Wide summit crater
 Usually only erupts once

Composite Volcanoes
Also known as a stratovolcano
 Most recognizable of all volcanoes
 Form from both explosive eruptions and quieter
flows of lava
 Broad base and steep sides
 Erupts many times (every hundred years or so)
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