1

Warm-Up: Thurs 2/20

• Write What You Know!

–Write everything you know about the prompt

below for five minutes, try for at least 3-4

complete sentences.

• What kind of magma forms explosive

eruptions? What kind of magma forms

quiet eruptions?

• definition in own words

• facts

• pictures

• definition in own words

• facts

• pictures

Volcanic Landforms Notes2/24/2014

Key Term

Key Term

Major Key Term definition in own words

Volcanic Landforms

• Shield Volcano

– wide, gently sloping volcano

– looks like a shield from the above

– formed by quiet eruptions and runny, thin lava

Volcanic Landforms

• Cinder Cone Volcano

– steep, cone-shaped hill or mountain

– formed by explosive eruptions of ash, cinders, and

bombs

Volcanic Landforms

• Stratovolcano (Composite Volcano)

– very large, cone-shaped mountain formed by

alternating quiet and explosive eruptions

– volcano layers made of alternating lava flows and

pyroclastic flows (ash, cinders)

– Most dangerous type, associated with Ring of Fire!

Volcanic Landforms

• Lava Plateau

– Thin, runny lava flowing out of fissures (long cracks)

can create high level areas made of basalt (lots of

these in Idaho!)

2

Volcanic Landforms

• Caldera– a huge hole left by the collapse of a

volcanic mountain or supervolcano

Magma Landforms

• Magma Landforms– formed by magma cooling underground, then

exposed by weathering away of surface layers

– Neck: magma that hardened in volcano’s pipe, looks like a giant tooth

– Dike: magma that forced itself between rock layers vertically (up-and-down)

– Sill: magma that forced itself between rock layers horizontally (flat)

Magma Landforms

• Batholith

– Formed when a magma chamber

cools into rock deep underground,

forms core of some mountain

ranges

– Dome Mountain: uplift forces a

batholith up to form a mountain

Half-Dome

Mountain in

Yosemite

Natl. Park