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Volcano Term Definitions
The resistance of a mineral to scratching.
A continuous release of seismic energy typically associated with the underground movement of magma. It contrasts distinctly with the sudden release and rapid decrease of seismic energy associated with the more common type of earthquake caused by slippage along a fault.
Movement of heat from one place to another.
Material is made up of a heterogeneous mix of different rock types. Instead of being composed on one rock type, it is composed of fragments of many different rocks.
The time period from 10,000 years ago to the present. Also, the rocks and deposits of that age.
A block of the earth's crust, generally long compared to its width, that has been uplifted along faults relative to the rocks on either side.
A volcanic center, 60 to 120 miles (100 to 200 km) across and persistent for at least a few tens of million of years, that is thought to be the surface expression of a persistent rising plume of hot mantle material. Hot spots are not linked to arcs and may not be associated with ocean ridges.
Volcanoes related to a persistent heat source in the mantle.
An underground zone of porous rock containing hot water.
The place on a buried fault where an earthquake occurs.