Hawaiian Eruption
In a Hawaiian eruption, fluid basaltic lava is thrown into the
air in jets from a vent or line of vents (a fissure) at the summit or on the
flank of a volcano. The spatter created by bits of hot lava falling out
of the fountain can melt together and form lava flows, or build hills called
spatter cones. Lava flows may also come from vents at the same time as
fountaining occurs, or during periods where fountaining has paused. Because
these flows are very fluid, they can travel miles from their source before they
cool and harden.
Strombolian Eruption
Strombolian eruptions are distinct bursts of fluid lava (usually
basalt or basaltic andesite) from the mouth of a magma-filled summit conduit.
The explosions usually occur every few minutes at regular or irregular
intervals. The explosions of lava, which can reach heights of hundreds of
meters, are caused by the bursting of large bubbles of gas, which travel upward
in the magma-filled conduit until they reach the open air. Products of an explosive eruption are often collectively called tephra.
Vulcanian Eruption
A Vulcanian eruption is a short, violent, relatively small
explosion of viscous magma (usually andesite, dacite, or rhyolite). This type
of eruption results from the fragmentation and explosion of a plug of lava in a
volcanic conduit, or from the rupture of a lava dome (viscous lava that piles
up over a vent). Vulcanian eruptions create powerful explosions in which
material can travel faster than 350 meters per second (800 mph) and rise
several kilometers into the air. They produce tephra, ash clouds, and
pyroclastic density currents (clouds of hot ash, gas and rock that flow almost
like fluids).
Vulcanian eruptions may be repetitive and go on for days,
months, or years, or they may precede even larger explosive eruptions.
Plinian Eruption
The largest and most violent of all the types of volcanic
eruptions are Plinian eruptions. They are caused by the fragmentation of gassy
magma, and are usually associated with very viscous magmas (dacite and
rhyolite). They release enormous amounts of energy and create eruption columns
of gas and ash that can rise up to 50 km (35 miles) high at speeds of hundreds
of meters per second. They can produce falls of ash, scoria and lava bombs miles from the
volcano, and pyroclastic density currents that raze forests, strip soil from
bedrock and obliterate anything in their paths.
Lava Domes
Lava domes form when very viscous, rubbly lava (usually
andesite, dacite or rhyolite) is squeezed out of a vent without exploding. The
lava piles up into a dome, which may grow by inflating from the inside or by
squeezing out lobes of lava (something like toothpaste coming out of a tube).
These lava lobes can be short and blobby, long and thin, or even form spikes
that rise tens of meters into the air before they fall over. Lava domes may be
rounded, pancake-shaped, or irregular piles of rock, depending on the type of
lava they form from.
Lava domes are not just passive piles of rock; they can
sometimes collapse and form pyroclastic density currents, extrude lava flows,
or experience small and large explosive eruptions (which may even destroy the
domes!)
Surtseyan Eruption
Surtseyan eruptions are a kind of hydromagmatic eruption, where
magma or lava interacts explosively with water. In most cases, Surtseyan
eruptions occur when an undersea volcano has finally grown large enough to
break the water's surface; because water expands when it turns to steam, water
that comes into contact with hot lava explodes and creates plumes of ash, steam
and scoria. Lavas created by a Surtseyan eruption tend to be basalt, since most
oceanic volcanoes are basaltic.
now i'm aware of the different explosions i might choose this as my aspect of volcano's.
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