xenolith

views updated May 08 2018

xenolith An inclusion or enclave of a preexisting rock in an igneous rock. Xenoliths are often derived from the country rocks that have been invaded by the igneous mass, and they frequently show some evidence of reaction, e.g. rounding of their edges and metamorphism.

xenolith

views updated Jun 08 2018

xen·o·lith / ˈzenəˌli[unvoicedth]; ˈzēnə-/ • n. Geol. a piece of rock within an igneous rock that is not derived from the original magma but has been introduced from elsewhere, esp. the surrounding country rock.