The Restless Earth: Super-volcanoes Flashcards
Super volcanoes are much…
Bigger than a standard volcano.
Where are super volcanoes found?
Destructive plate boundaries.
Over parts of the mantle that are really hot.
What are really hot places over the mantle where rocks melt called?
Hotspots.
What place is on top of a super volcano?
Yellowstone National Park, USA.
What is step 1 on how a hotspot is formed?
Magma rises up through cracks in the crust to form large magma basin below the surface.
Pressure of magma causes circular bulge on the surface.
How big is the circular bulge on the surface?
Several kilometres wide.
What is step 2 on how a hotspot is formed?
Bulge cracks, creating vents for lava to escape through.
Lava erupts out of vents causing earthquakes, sending up big plumes of ash/rock.
What is step 3 on how a hotspot is formed?
Magma basin empties.
Bulge is no longer supported so it collapses.
What happens when the bulge collapses?
More lava spews up.
What is step 4 on how a hotspot is formed?
Eruption has finished there’s a big crater left where the bulge collapsed.
What is the big crater called?
A caldera.
What does the big crater sometimes get filled with?
Water to form a large lake.
Name a lake which was formed from a big crater?
Lake Toba, Indonesia.
Name 3 characteristic of a super volcano
Flat.
Covers a large area.
There is a caldera.
Super volcanoes are flat unlike…
Normal volcanoes, which are mountains.
The area of land they cover is…
Bigger than a normal volcano.
Super volcanoes have a caldera unlike…
Normal volcanoes, where there’s just a crater at the top.
When a super volcano erupts there will be…
A global consequence.
An eruption of a super volcano hasn’t happened for how long?
Tens of thousands of years.
When was the last super volcano to erupt?
Lake Toba super volcano.
74 000 years ago.
What will a super volcano will throw out?
Thousands of cubic kilometres of rock, ash, lava.
How much ash, lava and rock does a normal volcano throw out?
Couple of cubic kilometres.
What will flow from the volcano?
Thick cloud of super-heated gas/ash that flows at high speeds.
What does the thick cloud of super-heated gas/ash that flows at high speeds do?
Kills, burns and buries everything it touches.
Everything within ______ will be destroyed
10 miles.
What will the ash do shooting out from a super volcano?
Shoot kilometres in to the air.
Block out almost all daylight over whole continents.
What can the blocking out of daylight do?
Trigger mini ice ages.
As less heat energy from the sun gets to the Earth.
The ash will settle over…
Hundreds of square kilometres.
Burying fields and buildings
