Volcanoes

Magma

Hot liquid rock found inside the Earth

Lava

Hot liquid rock found outside Earth's surface

Volcano

Mountain that forms when magma pushes up through the Earth's surface

Convergent plate boundary

Plates come together "collide"

Divergent plate boundary

Plates move apart

"divide"

Hot spot

Very hot places in the mantle where magma rises up & melts through the crust above

Ring of Fire

Big volcano zone almost all the way around the Pacific Ocean

Mid-Ocean Ridge

Large underwater mountain chain at places where plates move apart

Magma chamber

Pockets of molten rock inside volcanoes

Conduit

Tube in the middle of a volcano where magma comes up

Vent

Opening where magma comes out of a volcano

Shield volcano

Huge and wide (the biggest)

Cinder cone volcano

Tiny and steep volcano (the smallest)

Composite volcano

Tall and steep volcano (middle-sized - look like mountains

Basaltic (Mafic)

magma

Dark magma that makes gentle, flowy eruptions (pahoehoe & aa are examples)

Andesitic magma

Light and dark magma that makes explosive eruptions

Granitic

(Felsic or Rhyolitic)

magma

Light magma that makes explosive eruptions

Plutons

Igneous rock that forms underground - "Intrusive"

Batholiths

irregularly shaped intrusions consisting of a coarse-grained igneous rock

Stocks

very similar to batholiths, just smaller in size

Laccolith

when magma forms in parallel rock layers, and the surrounding rocks bow upwards to create a dome shape.

Sill

when magma intrudes in to parallel rock layer and there is minimal distortion of the surrounding rock

Dike

an intrusion that cuts through (and across) preexisting rock layers

Tephra

the solid stuff that comes out of volcanoes

Viscosity

the resistance to flow

Craters

small, bowl-shaped depressions that surround the vent of a volcano

Calderas

very large depressions that surround the vent of volcanoes