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Volcanoes. What is a Volcano?. Hot Lava. Cold Rock. ACTIVE. Z. Z. z. DORMANT. EXTINCT. Mountains that erupt lava. Hawaii. How Hot is Lava?. 1160°C. Heat suit. USGS photo by R.L. Christiansen Jan.9, 1973. Measuring the temperature. Inside and below a Volcano. vent. cone.
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What is a Volcano? Hot Lava Cold Rock ACTIVE Z Z z DORMANT EXTINCT Mountains that erupt lava Hawaii
How Hot is Lava? 1160°C Heat suit USGS photo by R.L. Christiansen Jan.9, 1973 Measuring the temperature
Inside and below a Volcano vent cone magma chamber conduit
What is lava and magma? melt +crystals +bubbles
Where does magma come from? • A look inside the Earth Mantle Solid that flows Runny Outer Core Crust Solid Inner Core Solid
Where does magmacome from? • A look at the mantle and crust Crust Mantle
Why do volcanoes erupt? Hot air Cold air Ocean Cold Crust HotMelt HotMantle Cooler Mantle
How do they erupt? • EXPLOSIVE • EFFUSIVE magma magma Sticky Lots of Bubbles Runny Not many bubbles
How do they erupt? • EFFUSIVE • EXPLOSIVE Sticky Lots of Bubbles! Runny Not many Bubbles Hawaii
Explosive Volcanoes Montserrat Montserrat Ash Fall Pyroclastic Flow Pyroclastic Flow Courtesy of www.swisseduc.ch Pyroclastic Flow
Effusive Volcanoes • ’a’a • Pahoehoe Aaflows Pahoehoe flows Rough Lots of pieces Smooth or Ropy Courtesy of A. Rust Courtesy of A. Rust
Where can we find volcanoes? Courtesy of Smithsonian Institution Global Volcanism Program World map of volcanoes erupted within the past 10,000 years
Activity Whathelps make explosive eruptions? • Making a Volcanic Eruption • You will need: • 2 litre bottle of soda or cola • 1 roll of mints
Activity USGS/Hawaiian Volcano Observatory Photo by J.D. Griggs Bubbles
Volcanic Hazards Danger to People, Places and Things
Volcanic Hazards Bent bars of a broken house. Which way did the flow go? Fast flowing rocks! • Explosive:Pyroclastic Flow • Flows sweeping away buildings
Volcanic Hazards • Explosive:Burial • Flows burying buildings
Volcanic Hazards • Explosive:Burns • Hot flows burning trees and buildings.
Volcanic Hazards • Explosive:Lahars • Fast flowing water and rock
Volcanic Hazards • Explosive:Ash Fall • Ash falling from eruption USGS/Cascades Volcano Observatory Photo by David Wieprecht
Volcanic Hazards Effusive:Lava Flows Pahoehoe flows Courtesy of Swisseduc.ch
Volcanic Hazards • Noxious Gas • Magma loses bubbles • Gas leaks into the air
Volcanic Hazards Japan • Earthquakes • Magma pushes on crust • Shakes and breaks buildings and roads
Volcanoes Examples from Past and Present Courtesy of www.swisseduc.ch
Pompeii • Vesuvius, Italy – 79AD • Explosive • Ash and flows covered Pompeii
Pompeii cc. of Crew Creative cc. Crew Creative Gladiator’s Barracks Pompeii Excavations
Pompeii Plaster casts of bodies
Pompeii Naples Vesuvius Bay of Naples Pompeii Courtesy of www.swisseduc.ch Vesuvius today
Pelée Before After Mt. Pelée, Martinique - 1902
Pelée Why? Photo by Angelo Heilprin 29,000 people died 2 survived
Heimaey Vestmannaeyjer, Iceland - 1973
Heimaey Lava flows caught people by surprise
Heimaey Spraying seawater to slow or stop lava flows
? Question What can we do to help people who live near active volcanoes? Mt. St. Helens 1. Look and Learn 2. Watch Active Volcanoes 3. Escape Plans 4. Find out why people live near volcanoes 5. Teach
Volcano Monitoring Volcano Observatories on Active Volcanoes
Volcano Monitoring tiltmeter magma tiltmeter tiltmeter magma Ground bulging or popping up
Volcano Monitoring Earthquakes
Volcano Monitoring Gas or Bubbles
Brain Challenge Questions about Volcanoes Photo: Tom Pfeiffer / www.volcanodiscovery.com
Brain Challenge V____ e n t What is a volcano? Mountains that erupt . l a v a Cone Lava is very: hotcold Conduit A dormant volcano is: awake asleep M a g m a ________ chamber What is lava and magma? m + bubbles + crystals e l t Why do volcanoes erupt? Hot magma wants to go: up down How do volcanoes erupt? Two types: e and effusive . x p l o s i v e What helps make explosive volcanoes erupt? . b u b b l e s Explosive volcanoes erupt a lot of into the air. a s h Do effusive volcanoes have runny or sticky lava? . r u n n y Can lava burn trees and houses? yes Can you outrun a pyroclastic flow? no Questions
Danger on the Island C Active B Extinct A Extinct N 3km Where can people live safely on the island?
Montserrat Pyroclastic Flow Courtesy of www.swisseduc.ch Real-Life Scenario