1. Volcanoes are Hot StuffBy
Shana Huffaker And Doreen Snyder
Modified by Mr. Kennedy

2. What is a Volcano?
Volcano- Areas of earth’s surface through which magma and volcanic gases pass
Volcano comes from the Roman word Vulcan, which means “fire”
Magma rises because it is less dense than the solid rock around it.

3. What are the parts of a Volcano?
VENT- the vent is the opening from which lava flows. Dust, ash, and rock particles can also be thrown out of the vent!

4. A lava flow is the area covered by lava as it pours out of a vent
A crater is a bowl-shaped area that may form at the top of a volcano around the central vent

5. Craters, Calderas, and Lava Plateau
From explosions of material out of the vent and the collapse of material back into vent
Caldera
Much larger depression that forms when magma chamber empties and its roof collapses
Lava Plateau
Forms when lava erupts from long cracks, or fissures, and spreads out evenly (thousands of km)

6. How are volcanoes formed?

7. Deep in the earth it is very hot. It is so hot that rocks melt
Deep in the earth it is very hot. It is so hot that rocks melt. The melted rock is called magma. The magma is lighter than the rocks around it so it rises. Sometimes it finds a crack or hole in the earth’s crust and bursts through. This is how a volcano begins.

8. Why do volcanoes erupt?

9. Pressure builds deep in the earth where the magma is
Pressure builds deep in the earth where the magma is. Suddenly the gases escape and violently explode. It is kind of like toothpaste squirting out of a tube when you give it a hard squeeze.

10. What are the different kinds of volcanoes?

11. Volcanoes do not all look alike
Volcanoes do not all look alike. Their shape is based on what type of materials they erupt. There are three main kinds, or shapes, of volcanoes.

12. 3. Volcanic cone- is the pile of lava, dust, ashes, and rock around the vent. It can be found in different shapes!

13. Types of Volcanoes Shield volcano Cinder cone volcano
Composite volcano

14. Shield Volcanoes

15. Volcanoes that build up from many slow, steady, flows of hot lava, are called shield volcanoes. This kind of volcano is low and broad with gently sloping sides. They look like a warriors shield.

16. Shield Volcano Is wide and somewhat flat.
It forms from a quiet eruption.
Lava flows out quietly and for great distances.

18. Cinder Cone Volcanoes

19. Cinder cone volcanoes form when solid rock and ash shoot up into the air and fall back around the volcano opening. The cinder cone volcano has steeply sloped sides.

20. Cinder Cone Volcano Has tall, very steep sides.
Has explosive eruptions.
This eruption produces a lot of cinder and ash.

22. Strato or Composite Volcanoes

23. Strato volcanoes, also called composite volcanoes, erupt with molten lava, solid rock, and ash. The layers pile up much like layers of cake and frosting. The layers form into symmetrical cones, and the slopes are steep.

24. Composite Volcano Form from explosive eruptions.
Produce a lot of lava and ash.
Is small, with steep sides.

26. What’s inside a volcano?
Magma Chamber- molten rock that feeds a volcano
Vents- cracks in the crust
What is the difference between magma and lava?

27. Types of Volcanoes Shield Volcano Built from layers of lava
Non-explosive eruptions
Not very steep, but can be big

28. Types of Volcanoes Cinder Cone Volcano Built from pyroclastic material
Moderately explosive, short eruptions
Small in size, steep slopes

29. Types of Volcanoes Composite Volcanoes Most common type
Explosive eruptions and lava flow
Built from pyroclastic material AND lava

30. What Erupts from a Volcano?
Blocky lava
Lava can be
thick or thin.
Pahoehoe Aa
Pillow lava

31. What Erupts from a Volcano?
Pyroclastic material
Rock fragments created by eruptions
magma explodes from volcano and solidifies in the air
existing rock is shattered by powerful eruptions
EXPLOSIVE
Lapilli
Volcanic bombs
Volcanic blocks
Volcanic ash

32. How do volcanologists predict eruptions?
Measuring Small Quakes
Before eruption, increase in number & intensity
Measuring Slope
Bulges may form with magma (tiltmeter)
Measuring Volcanic Gases
Outflow of volcanic gases
Sulfur dioxide, carbon dioxide
Measuring Temperature from Orbit
Measure changes in temperature over time

33. There is much more about volcanoes out there
There is much more about volcanoes out there. Look in books and on the internet . Have Fun!

34. Pictures, Images, and information From:
Soames Summerhays/Photo Researchers, Inc.
Kraft-Explorer/Photo Researchers Inc.
Masao Hayashi-Dung/Photo Researchers Inc.
Why Do Volcanoes Blow Their Tops? By Melvin and Gilda Berger