Download Inside Earth: Chapter 1- Plate Tectonics

Volcanoes
: Volcanic Landforms
• What landforms does lava create on
Earth’s surface?
• How does magma that hardens
beneath the surface create
landforms?
Landforms From Lava & Ash
Shield Volcano
• A wide, gentlysloping mountain
made of layers of
lava and formed by
quiet eruptions
• Example: The
Hawaiian Islands
Cinder Cone
• A steep, coneshaped hill or
mountain made of
volcanic ash,
cinders, and bombs
piled of around a
volcano’s opening
• Example: Sunset
crater in Arizona
Composite Volcano
• A tall, cone-shaped
mountain in which
layers of lava
alternate with layers
of ash and other
volcanic materials
• Example: Mount St.
Helens in Washington
and Mount Fuji in
Japan
Caldera
• The large hole at
the top of a
volcano formed
when the volcano’s
magma chamber
collapses
What are the three types of
volcanic mountains?
• The three types of volcanic mountains
are
• Shield volcanoes
• Cinder cone volcanoes
• Composite volcanoes
What landforms does lava
create on Earth’s surface?
Explain how each landform is
formed.
•
•
•
•
Shield volcanoes
– Lava pours out of the volcano’s vent and hardens creating new
layers of rock
Cinder cone volcanoes
– Ash, cinders, and bombs pile up around the volcano vent in a
cone-shaped pile
Composite volcanoes
– Quiet eruptions (lava flow) alternate with explosive eruptions
(ash, cinders, and bombs) creating a tall cone-shaped mountain
Lava plateaus
– Lava fills the cracks in Earth creating higher elevated, flat land
Landforms From Magma
Volcanic Neck
• A deposit of
hardened magma in
a volcano’s pipe
• Looks like a giant
tooth stuck in the
ground
Dike
• A slab of volcanic
rock formed when
magma hardens in a
vertical crack
Sill
• A slab of volcanic
rock formed when
magma hardens in a
horizontal crack
Compare and Contrast
What is the difference between a
dike and a sill?
• Both a dike and a sill form when
magma hardens in a crack
• A dike forms when magma hardens
into a vertical crack
• A sill forms when magma hardens into
a horizontal crack
Batholith
• A mass of rock
formed when a
large body of
magma cooled
inside the crust
How does magma that hardens
beneath the surface create
landforms?
• Volcanic necks
– Magma hardens inside the volcano’s pipe and the
softer layer around the pipe wears away
• Dikes
– Magma forces its way into vertical cracks in the
crust and hardens
• Sill
– Magma squeezes between horizontal layers of
rock and hardens