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Volcanoes are Hot Stuff!. Created & Adapted by: Dawn Easley. VOLCANOES. EQ : What are the types of volcanoes and how are they formed?. So, What Is a Volcano?. A volcano is a weak spot in the crust where molten material, or magma, comes to the surface.
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Volcanoes are Hot Stuff! Created & Adapted by: Dawn Easley
VOLCANOES EQ: What are the types of volcanoes and how are they formed?
So, What Is a Volcano? • A volcano is a weak spot in the crust where molten material, or magma, comes to the surface.
The Ring of Fire The Ring of Fire is a volcano belt formed by many volcanoes that border the Pacific Ocean. Subduction zones
Deep in the earth it is very hot and rocks melt. The melted rock is called magma and 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 it (vent). This is how a volcano begins.
Pressure builds deep in the earth where the magma is. Suddenly the gases escape and violently explode.
Look up, there’s a fire burning! Way up, in a mountain high. Look up, when there’s steam, smoke, or ashes. When the crater starts to blow. And the lava starts to flow. Then you will surely know. It’s a volcano! It’s a volcano! Look down, in the earth’s deep zone Way down, under the soil & rock. You’ll find that there’s magma burning. Pushing up through the plates in the rock crust. Trying to start a fireworks show. And when the lava starts to flow. It’s a volcano! It’s a volcano! Nature’s always changing everything we see. Always rearranging under the land and in the sea. It’s a volcano! It’s a volcano! Three kinds of volcanoes can happen Composite, Shield, or Cinder Cone. But when the earth starts shaking And the lava starts to flow. It doesn’t matter which one blows. For then you will surely know. It’s a volcano! It’s a volcano! It’s a Volcano!
Classifying Volcanoes • Cinder Cone • Shield • Composite or Strato • Active • Intermittent • Dormant • Extinct Regular Constant Sleeping Never
VOLCANIC ACTIVITY ACTIVE - A volcano that has erupted in the recent past and is expected to erupt again. INTERMITTENT – A volcano that erupts in fairly regular time periods. DORMANT - A “sleeping” volcano. A volcano that has not erupted in the recent past, but could erupt again. EXTINCT - A volcano that is not expected to erupt again.
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 warrior’s shield.
Shield Volcanoes • A shield volcano is a large, gently sloped volcano made up from many slow, steady flows of hot lava. Low and broad – like a warrior’s shield. • Materials Erupted: mainly liquid lava, so the volcano is made of layers of hardened lava. • Non-explosive eruptions • Example: the volcanoes of Hawaii **Click picture for video.
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.
Cinder Cone Volcanoes • A cinder cone volcano is a relatively small, volcano with steep sides. It is where rock and ash shoot up into the air and fall back around the opening. • Materials Erupted: small pieces of hardened lava (rock fragments) - called cinders • Moderately explosive • Example: Paricutin (Mexico) **Click picture for video.
Stratovolcanoes, 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.
Composite Volcanoes • A composite volcano is a huge mountain-like volcano. Layers build up like frosting on a cake forming a cone with steep sides. • Materials Erupted: sometimes lava, sometimes rock fragments. • May have very explosive eruptions • Example: Mount St. Helens **Click picture for video.
Volcano Research You will be assigned a volcano to research. Each volcano has something interesting and unique about it - find out what it is! For each volcano you will be researching *Where is the volcano located ? *When did the famous eruption occurred? *What type of volcano it is? *What is unique or interesting about the volcano? *Is the volcano active, dormant or extinct? **Some helpful websites are listed on the next slide . . .
Try these sites to get your research started: Hawaii Volcanoes Volcano World Smithsonian Volcano Page Volcanoes Live Encyclopedia.com (type in volcano name) Info. on Mount St. Helens Info. on Mount Rainier Encarta (type in volcano name) Volcanoes Listed by Name U.S. Geological Survey - volcano page
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 www.usgs.gov/education/learnweb/volcano/index.html