Transcript VOLCANOES

~Volcanoes~
BY: ~Allison Whittingslow~
&&
~Carlie Ivey~
What is a volcano?
VOLCANO: vents or
fissures in the earth's
crust through which
gases, molten rock, or
lava , and solid
fragments are
discharged.
What is the difference of lava and
magma?
 Magma-it is
inside of a
volcano.
 Lava-it
outside of the
volcano.
What is a hot spring?
 Hot spring: natural
discharge of groundwater
having an elevated
temperature. Most hot
springs result from the
emergence of
groundwater that has
passed through or near
recently formed, hot,
igneous rocks.
What is a geyser?
Geysers: hot
spring from
which water and
steam are
ejected
periodically to
heights ranging
from a few to
several hundred
feet.
The 3 types of volcanoes!
Shield
Composite
Cylinder
What is Pahoehoe?
Hot fast
moving lava.
From quiet
eruptions.
What is AA?
A volcano erupts
explosively if its
magma is thick. The
magma plugs the
volcanoes pipe, and
pressure builds up
until the trapped
gases explode, forcing
the magma out.
What is silica?
Silica content of
magma helps to
determine whether
the volcanic
eruption is quiet or
explosive.
Why do volcanoes erupt?
Volcanoes erupt because of
density and pressure. The
lower density of the magma
relative to the surrounding
rocks causes it to rise. It will
rise to the surface or to a
depth that is determined by
the density of the magma and
the weight of the rocks above
it. As the magma rises,
bubbles start to form from the
gas dissolved in the magma.
The gas bubbles exert
tremendous pressure. This
pressure helps to bring the
magma to the surface and
forces it in the air, sometimes
to great heights.
Designers
**Allison&Carlie**
~THE END~
MS. NIX
EARTH SCIENCE
6*2