xenolith
/ˈzɛnəˌlɪθ/
noun
- A piece of rock that is different from the rock around it and was picked up by magma (hot liquid rock) as it moved upward.
- Scientists study xenoliths to learn about the Earth's mantle.
- This unusual xenolith contains minerals not found in the surrounding lava.
- The geologist found a dark xenolith inside the lighter volcanic rock.