intrusive rock
geology
Also known as: intrusive igneous rock, plutonic rock
- Also called:
- plutonic rock
- Related Topics:
- granite
- diabase
- gabbro
- anorthosite
- nepheline syenite
intrusive rock, igneous rock formed from magma forced into older rocks at depths within the Earth’s crust, which then slowly solidifies below the Earth’s surface, though it may later be exposed by erosion. Igneous intrusions form a variety of rock types. See also extrusive rock.