laccolith

[ lak-uh-lith ]

noun

, Geology.

1. a mass of igneous rock formed from magma that did not find its way to the surface but spread laterally into a lenticular body, forcing overlying strata to bulge upward.

laccolith

/ ˈlækəlɪθ; ˈlækəˌlaɪt; ˌlækəˈlɪtɪk /

noun

1. a dome-shaped body of igneous rock between two layers of older sedimentary rock: formed by the intrusion of magma, forcing the overlying strata into the shape of a dome See lopolith

laccolith

/ lăk′ə-lĭth′ /

1. A body of igneous rock intruded between layers of sedimentary rock, resulting in uplift. Laccoliths are usually plano-convex in cross-section, having a flat bottom and a convex top, and are roughly circular in plan. They are usually connected to a dike and are typically up to 8 km (5 mi) in diameter and tens to hundreds of meters thick.
2. See illustration at batholith

Derived Forms

• ˌlaccoˈlithic, adjective

Other Words From

• lacco·lithic lac·co·lit·ic [lak-, uh, -, lit, -ik], adjective

Word History and Origins

Origin of laccolith¹

1875–80; < Greek lákko ( s ) pond + -lith

Word History and Origins

Origin of laccolith¹

C19: from Greek lakkos cistern + -lith