What is magma?

Magma is composed of molten rock and is stored in the Earth's crust. Lava is magma that reaches the surface of our planet through a volcano vent. Lava flow, Hawai. Courtesy of the U.S. Geological Society. read more

Magma, as liquid, typically forms in high-temperature, low-pressure environments within several kilometers of the Earth's surface. After formation, magma compositions may be changed by fractional crystallization, contamination, or magma mixing. Rock formed of solidified magma is called igneous rock. read more

Magma is a molten and semi-molten rock mixture found under the surface of the Earth. On the rare occasions when magma breaks the surface, as in a volcanic eruption, it is called lava. This lava lake sits in Mount Nyiragongo, Democratic Republic of Congo. read more

Magma definition, molten material beneath or within the earth's crust, from which igneous rock is formed. See more. read more