Supervolcanoes
Aims
To be able to locate and label
Supervolcanoes
To distinguish between Supervolcanoes
and Volcanoes.
What is a Supervolcano? How is it different to a regular
Volcano?
Supervolcanoes are on a much
bigger scale than normal volcanoes.
A Volcano becomes ‘Super’ when it
emits in excess of 1,000km3 of
material.
Supervolcanoes appear different to
other volcanoes. They have large
depressions in the centre known as
Calderas which are ringed by
smaller craters. These craters are
often joined up by fissures to form
the caldera.
Tasks
1. Use the internet to
find the definitions
of the words in red
The Location of Volcanoes and Supervolcanoes
Use the internet to mark the locations of Volcanoes and
Supervolcanoes on the map above.
KEY: Use Red triangles for Volcanoes and Yellow squares for
Supervolcanoes
Define the following terms:
• Geothermal
• Geyser
• Hot spot
WATCH THE VIDEO CLIPS ON THE HAZARDS WEBPAGE ON
SUPERVOLCANOES
This supervolcano, located in Yellowstone National Park, USA
threatens the existence of people – at the very least those in
North America, if not globally.
Many visitors stand in awe looking at Old Faithful and the
geothermal features of the Norris Geyser basin without realising
the vulnerability of where they are standing.
Old Faithful
Norris Geyser
There is evidence that the magma beneath Yellowstone is moving.
The caldera is bulging up below Lake Yellowstone and in places
the ground has risen 70cm in places.
The magma chamber underneath Yellowstone is 80km long, 40km
wide and 8km deep. It is not known whether the magma is on top
of other materials which would be needed for an eruption.
The most recent eruption at this hot spot was 630,000 years ago
(before that it erupted 1.3 and 2 million years ago). An eruption
today would have a catastrophic effect. The Yellowstone
supervolcano has a magma chamber five times the minimum size
for a supervolcano eruption.
Diagram of the area affected by the last 2
Yellowstone eruptions
The Effects of an Eruption at Yellowstone
• 10,000 km2 of land will be destroyed.
• 87, 000 people will be killed.
• 15cm of ash would cover buildings within 1,000km.
• Ash will affect transport, electricity, water and farming.
• Lahars (mudflows due to ice mixing with melting ice or water).
• Ash would fall on the UK 5 days later.
• Globally climates would change, crops would fail and many
people would die.
Contrast Supervolcanic eruptions with regular Volcanic eruptions.
Mt St Helens
Yellowstone
Location
North West USA
West USA
Plate Boundary
Destructive – North
American/Juan de Fuca
Hot Spot
Classification
Active
Dormant
Last eruption affected area
Ash zone 39km from
crater
Ash zone 3200km from
crater
Last eruption volume of material
2 cubic metres
2,000 cubic metres
Last eruption other
effects
53 deaths
Possible extinction of
all life on the North
American continent