- REDIRECT
Magma (from
Greek μάγμα, "thick unguent") is a mixture of molten or semi-molten
rock, volatiles and solids that is found beneath the surface of the
Earth, and is expected to exist on other
terrestrial planets. Besides molten rock, magma may also contain suspended crystals, dissolved gas and sometimes gas bubbles. Magma often collects in
magma chambers that may feed a
volcano or solidify underground to form an
intrusion. Magma is capable of intrusion into adjacent rocks (forming
igneous dikes and
sills), extrusion onto the surface as
lava, and explosive ejection as
tephra to form
pyroclastic rock.