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Molten rock, underground.


A weak spot in the crust where magma can escape.


Molten rock, above ground

Ring of Fire

A major volcanic belt, formed by the many volcanoes that rim the pacific ocean.


Fast moving, hot lava, low viscosity. Looks like a solid mass of rope-like coils.


Cooler, slower-moving lava, high viscosity. Rough, jagged surface.

Island Arc

A string of islands formed by the volcanoes along a deep-ocean trench.

Hot Spot

Volcano where magma from the mantle melts through the crust.


A liquids resistance to flowing.


A material found in magma. Causes explosive eruptions.

Magma Chamber

The pocket beneath a volcano where magma collects.


A long tube through which magma moves from the magma chamber to the earth's surface.


Same as pipe.

Lava Flow

The area covered by lava as it pours out of a volcano's vent.


The top of a volcano.

Pyroclastic Flow

Expulsion of ash, cinders, bombs, gasses


A volcano that is not active, but isn't dead yet


The volcano will never erupt again supposedly

Shield Volcano

Wide, gently sloping, made of lava layers, quiet eruptions

Composite Volcano

Steep, alternates between quiet and explosive eruptions, made of lava and pyroclastic flow

Cinder Cone Volcano

Steep, explosive eruptions, made out of pyroclastic flow


The large hole at the top of a volcano formed when the roof the magma chamber collapses.

Volcanic Neck

A deposit of hardened magma in a volcano's pipe.


Vertical pathways of magma


Horizontal pathways of magma


A mass of rock formed when a large body of magma cools inside the crust.


A fountain of water and steam that builds up pressure underground and erupts at regular intervals.


Small rocks


Huge rocks

Hot Springs

When there is a crack in the crust underwater, so that the water is heated

Mud Pots

Boiling pot of mud

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