Download ppt: volcano intro hook

What is a volcano?
• An opening to the interior of the planet
• What comes out of this opening can tell us about
what is going on in the inside
What do we know about volcanoes?
In your table groups brainstorm what you know about volcanoes
Where do we find volcanoes?
What do they look like?
Why aren’t all volcanoes the same?
Understanding why material comes out of a volcano
explosively in one spot and not at another is related to
what’s happening under the surface
In your table groups, brainstorm two lists:
What you think are similarities among all volcanoes
and
What are some differences among volcanoes
Hazards vocabulary
• Tephra– Generic term for any airborne material erupted
• Pyroclastic flow– Mixture of solid & semi-solid fragments, and hot
gases which flow down the side of a volcano.
Moves somewhat like a snow avalanche
Hazards vocabulary
• Lahar– Volcanic mudflow. Water mixes with tephra; can come
from lakes on the mountain or melted ice & snow. Moves
somewhat like wet cement
• Lava flow– Streams of molten rock that pour or ooze from a vent.
Can ignite or bury anything it comes in contact with.
Others: ash fall, landslides, poisonous gases, tsunamis,
earthquakes, lava fountain
Volcanic
Hazards
Lahar
Pyroclastic
Flow
Fires
Ash Clouds
Ash
Volcanic Explosivity Index
• VEI based on erupted volume of material
• 1 up on the index = 10x as large
Kilauea (Hawaii)
Volcanic Explosivity Index: 0 (non-explosive)
Stromboli (Italy)
Volcanic Explosivity Index: 1 (gentle)
Galeras (Columbia)
Volcanic Explosivity Index: 2 (explosive)
Ruiz (Columbia)
Volcanic Explosivity Index: 3 (severe)
Galunggung (Indonesia)
Volcanic Explosivity Index: 4 (cataclysmic)
St. Helens (United States)- 1980
Volcanic Explosive Index: 5 (paroxysmal)
Pinatubo (Philippines)- 1991
Volcanic Explosivity Index: 6 (colossal)
Tambora (Indonesia)- 1815
1816- Year without a summer
Volcanic Explosivity Index: 7 (super-colossal)
Lake Toba (Indonesia) or Yellowstone (United
States): Super Volcano
Volcanic Explosivity Index: 8 (mega-colossal)
stop
Friday, 4/6
• Who has been to a volcano before?
Mount St. Helens