Molten Material
Magma that has reached the surface.
Lava
Volcano where ash and lava alternate layers, creating a tall cone-shaped mountain.
Composite Volcano
This material controls the fluidity of magma, made of silicon and oxygen.
Silica
Lava that is smooth and slow.
Pahoehoe Flow
Long, gently sloping volcanoes built by lava flows.
Shield Volcano
The measure of a liquids ability to flow.
Viscosity
Rough and jagged lava flow.
A'a Flow
When ash, cinders, and bombs build up around the vent of a volcano, creating a tall cone-shaped volcano.
Cinder Cone Volcano
Unusually hot areas deep under the Earth's surface.
Hot spots
A rapidly-moving flow of gas, pumice, ash, and rock fragments.
Pyroclastic Flow
Volcano that has never erupted in human history, and will probably never erupt.
Extinct Volcano
When pressure forces magma from a volcano, creating lava flows and clouds of ash.
Eruption
The extremely hot material found in the Earth's mantle, that becomes lava.
Magma
Volcanoes that are actively erupting or are expected to erupt soon.
Active Volcano
The movement of lava
Lava flow