Chapter 6
VOLCANOES
Plat = FLAT
LAVA
PLATEAU
High, from runny lava
build up
1. Cinder CONE
3 KINDS
of
2. COMPOSITE
3. SHIELD
VOLCANOES
Cinder CONE
VOLCANO
 Steep pile
 Ash, cinders, &
bombs build up
SILL
 Magma gets squeezed
between
HORIZONTAL layers
of rock
Batholith
Large body of magma
Cools INSIDE the crust
Dome
Mountain
Volcanoes on
smaller planets
v.
Earth
Blocked magma
pushes/bends
Rock layers UPWARD
 Mercury, Venus,
Mars smaller
 Their CORES
have cooled off
 Volcanoes
EXTINCT
volcanic
neck
Magma cooled in
volcano pipe – forms
volcanic neck
 Smooth surfaces we
see on moon are
EARTH’s MOON’s
volcanoes
King Neptune carried TRIdent
Lava flows from 3 billion
years ago!
volcanic
dike
Magma goes
ACROSS layers of rock
Circles the
Pacific Ocean
RING of FIRE
COMPOSITE
VOLCANO
 Composed of both
other kinds of material

Alternating layers of
LAVA & ASH
AA
Aaahhhhh … it’s moving so
SLOWLY !
From a QUIET eruption
SETS FIRE to
EVERYTHING
Silica
High in silica =
Thicker
EXPLOSIVE eruption
because it gets block with
thick magma, then blows!
2
Types
of
Lava
Pahoehoe = FLOWY; fast
FLOWY, flowy
Aa = SLOW moving;
Looks like land
Aa lava
Looks like land; walk on it
and yell “Aaaaa!”
3 Stages
of
Volcano’s Life
1. Active = Alive!
2. Dormant = sleeping
3. Extinct = dead
Dormant Stage
Of Volcano
Has not erupted in long,
long time
Probably won’t erupt any
time soon
Natural pool of heated
water
Hot spring
Geyser
Heated water SHOOTING
out
Geothermal
Earth + heat
1 . ash
= sand sized
3
Volcano
Particle
Sizes
2. cinder = pebble sized
3. bomb = bigger!
QUIET
Volcanic Eruption
Danger = Lava Flows
caldera
Huge hole left behind when
volcanic mountain collapses
Island
Arc
Island arcs form when
ocean plate collides with
ocean plate
Arc = Curve
Lava
vs
Lava = on Land
Magma = in middle of Earth
Magma
High silica = light color;
Thick; slow
SILICA levels
= darker color;
Thinner;
crater
Pyroclastic
Flow
The BOWL part of a
volcano
1.ash
2. cinders
3. bombs
4. gases
ALL that stuff!
Volcanoes
in Hawaii
1. cone
2. composite
3.
shield
Shield
Volcano
1. shaped like shield
2. lava flows
cinder cone
volcanoes
Ash, cinders, and bombs
build in a STEEP pile
LOUD eruption !
Pyroclastic Flows
Olympus Mons
Biggest volcano in whole
solar system!
On MARS
Hot spot
volcanoes
Hawaii
Why does magma flow
Upward
LESS dense; so it rises
Pipe = long tube
Parts of a Volcano
Crater = Bowl
Vent = OPENING
at end of pipe
SILICA in the magma
is like
OATMEAL
SEISMIC WAVEs and
Volcanoes
The MORE silica
The THICKER the magma
The LESS it
will flow easily
Earthquake waves
Uh-oh volcano is about to
erupt!