Transcript Volcano Types - Kenston Local Schools

Volcanoes
Animation of a volcano
Cinder Cone
Cinder Volcanoes are the
simplest type of volcano.
They are built from particles
and blobs of congealed lava
ejected from a single vent.
Lava is blown into the air,
which breaks into small
fragments that solidify and fall
as cinders around the vent to
form a circular or oval cone.
Most cinder cones have a
bowl-shaped crater at the
summit, and rarely rise more
than a thousand feet or so
above their surroundings.
Composite/Stratovolcano
Typically, composite volcanoes are steep-sided, symmetrical cones of large dimension built of
alternating layers of lava flow, volcanic ash and cinders. Composite volcanoes will rise as much as
8,000 feet above their base. Most composite volcanoes have a crater at the summit, which contains a
central vent or a clustered group of vents. One essential feature about composite volcanoes is the
conduit system. This is when the magma (molten rock material) from a reservoir deep in the Earth's
crust rises to the surface. This type of volcano is built by the accumulation of materials erupted
through the conduit, which increases in size as lava, cinders, and ash are added to its slopes.
Shield Volcano
Shield volcanoes are built almost entirely of fluid lava flow. Flow after flow pours out in all directions
from a central summit vent, which builds a broad, gently sloping cone - much like a warrior's shield or
a plateau. Shield volcanoes can be easily identified because they are tall and broad, with flat, rounded
shapes.
Olympus Mons
Location: Mars
Type: Shield volcano
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Olympus Mons a Latin term meaning "Mount Olympus" is the tallest known
volcano and mountain in our solar system
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Roughly the size of the American state of Arizona and three times taller
than Mt. Everest; about 20x wider than it is tall.
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The extraordinary size of Olympus Mons is likely due to the fact that Mars
does not have tectonic plates. Thus, the crust remained fixed over a hot
spot and the volcano continued to discharge lava, bringing it to such a
height. Formed the same way as the Hawaiian Islands.
Last Eruption: as recently as 40 mya; may still be an active volcano??
Mt. Pinatubo
Location: Philippines
Type: Composite volcano/stratovolcano
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Has had between 6 and 12 eruption cycles
Largest eruption was 35,000 years ago
Most of the volcano was blasted away in the 1991 eruption
Surrounded by smaller volcanoes that are actually vents to the
larger volcano
Last Eruption: 1991-1992, although it is still an active volcano
Mount Hood
Location: Oregon, USA
Type: Composite volcano/stratovolcano
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Tallest mountain in Oregon; the base is over 92 miles wide
Has had 4 active eruption periods in the last 15,000 years
Formed 500,000 years ago
Very popular with skiers, hikers and climbers; many communities would be
threatened by a modern day eruption of this volcano
Last Eruption: 1790's, not long before Lewis and Clark's expedition to
the Pacific Northwest
Kilauea
Location: Hawaii, USA
Type: Shield volcano
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Youngest volcano in Hawaii
One of the most active volcanoes
on Earth; over 90% of the surface
is covered in lava
Formed by a hotspot under the
Pacific plate
Most of the volcano is below sea
level
Has a large caldera
Last Eruption: November 2009
Paricutin
Location: Mexico
Type: Cinder Cone volcano
Facts:
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Grew in a cornfield in an eruption
that began in 1943; largest period
of growth was the first year,
continued to grow for 8 years
Lava flow covered 10 square
miles
It’s unique growth cycle allowed
scientists to study volcanoes more
closely
Last Eruption:1952
Mount Cotopaxi
Location: Ecuador
Type: Composite
volcano/stratovolcano
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Located in the Ring of Fire
Means “throne of moon”
Has erupted 50 times since 1783
Tallest volcano in Ecuador
It’s eruptions produced mudflows
that traveled over 60 miles
Last Eruption: 1904-has been
dormant for the last 35 years
Mount Saint Helens
Location: Washington, USA
Type: Composite/stratovolcano
Facts:
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Massive eruption in May, 1980 sent thousands of tons of ash into
atmosphere and covered 150 square miles; the top of the volcano was
destroyed in minutes; vegetation has yet to recover
Last Eruption: 2008
Mount Rainer
Location: Washington, USA
Type: Composite/stratovolcano
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Formed 730,000 years ago
Steepest volcano in Cascade range
Over the last 100,000 years the
erosion has been greater than the
growth; due to glaciers
Has a high number of avalanches;
covered in large amounts of ice and
snow
Last Eruption: 1894
Mauna Loa
Location: Hawaii, USA
Type: Shield volcano
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Largest volcano on Earth; one of the
most active
Began to form nearly 1 million years
ago
Makes up ½ the area of the island of
Hawaii
There is a caldera located at the
summit
Has erupted 15 x since 1900
Last Eruption: 1984
Mount Fuji
Location: Japan
Type: Composite/stratovolcano
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One of the most well-known volcanoes
Japan’s largest volcano/highest
mountain; actually made up of 3
volcanoes
Currently dormant
Eruptions have resulted in 0 fatalities
Has a large crater from the 1707
eruption
Has erupted 16 times since 781 AD
Last Eruption: 1707
Mount Shasta
Location: California, USA
Type: Composite/Stratovolcano
Facts:
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Second highest mountain in the
Cascades
Erupts approximately every 800
years
Comprised of 4 overlapping
eruption centers
Last Eruption: 1786
Mt. Etna
Location: Italy
Type: Composite
volcano/stratovolcano
Facts:
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One of the world’s most studied
volcanoes
Second largest active volcano in
Europe
One of the world’s largest
continental volcanoes
Surface is covered by historic lava
flows
Last Eruption: 2008