portals Into the Heart of the earth
they burn bottomless cauldrons fueled by
an ancient rat bubbling and boiling
thousands of miles beneath the surface
and just waiting to burst through
Location
volcanoes are scattered across
of volcanoes can be found across the
world though countless others are on the
ocean floor most volcanoes whether on
land or underwater are located where
tectonic plates meet
in fact the ring of fire a path that
traces the boundaries between several
tectonic plates around the Pacific Ocean
contains about 75 percent of the
planet’s volcanoes
Types
there are several types of volcanoes
primarily classified by shape and size
major types include
stratovolcanoes which often appear as
tall steep mountains
shield volcanoes which are flatter and
dome-shaped
calderas which are large depressions in
the ground
and mid-ocean ridges which are
underwater chains of volcanic mountains
The Journey
no matter their shape or size all
volcanoes emit gas and molten rock
the Journey of these emissions begins
deep underground in the Earth’s core
which can burn as hot as the surface of
the Sun transfers its heat to the
surrounding Rocky mantle in doing so the
heat melts some of the rock this molten
rock or magma is lighter than the
surrounding solid rock layer so it rises
through the mantle
the magma then escapes through vents in
the Earth’s crust causing volcanic
eruptions
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now above ground this magma is referred
to as lava and it can reach temperatures
of over 2000 degrees Fahrenheit
Hot Gas
in addition to Lava volcanoes May erupt
with searing Hot Gas formed in the
mantle in a phenomenon called
pyroclastic flow this gas combined with
hot ash can race down the sides of a
volcano as fast as 100 miles per hour
burning everything in its path
Vei
measure and classify eruptions
scientists develop the volcanic
explosivity index or vei it considers
various factors such as the volume of
lava gas and other emissions from the
volcano along with the height of the
eruption cloud above the Volcano Summit
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the vei scale begins at zero
excessive measurement increases
logarithmically meaning that each
magnitude is 10 times more powerful than
the one before it the vei scale does not
have an upper limit but the most
catastrophic eruptions measured thus far
are categorized as vei 8. these
eruptions occurred thousands and
millions of years ago
Mount Tambora
the most destructive volcanic eruption
ever witnessed occurred in Indonesia in
1815. Mount Tambora a large strata
volcano erupted with a vei measurement
of seven the blast caused earthquakes
tsunamis and pyroclastic flows that
decimated the land and took tens of
thousands of Indonesian lives
the eruption even destroyed the top of
Mount Tambora itself turning the 13 000
foot tall mountain into a
3640 foot deep Caldera
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while volcanoes are some of the most
destructive forces of nature they have
also helped make life on Earth possible
volcanic ash provides nutrients to
nearby soil making the land fertile
and lava when it cools hardens into rock
and creates new landforms
with heat from the heart of the earth
volcanoes have helped terraform the
planet making it the rich Dynamic
landscape
we see today
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