Encyclopedia > I > Igneous rock
Igneous rock
Igneous rocks are formed when rock (magma) cools and solidifies, with or without crystallisation, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks. This magma can be derived from partial melts of pre-existing rocks in either the Earth's mantle or crust.
Information are taken from Wikipedia, the open encyclopedia, to which contribute many volunteers from around the whole world. Texts are available under the following conditions GNU Free Documentation License.
Encyklopedie (cz) Encyklopédia (sk) Enzyklopädie (de)