- 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.
Also lac·co·lite [lak-uh-lahyt] /ˈlæk əˌlaɪt/.
Origin of laccolith
1875–80; < Greek lákko(s) pond + -lith
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- 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 domeSee lopolith
C19: from Greek lakkos cistern + -lith
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- 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. See illustration at batholith.
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