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A mass of igneous rock intruded between layers of sedimentary rock, resulting in uplift.

[Greek lakkos, pond, cistern + -lith.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ˈlækəlɪθ) or


(Geological Science) 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
[C19: from Greek lakkos cistern + -lith]
ˌlaccoˈlithic, laccolitic adj
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈlæk ə lɪθ)
a mass of igneous rock formed from magma that spread laterally into a lenticular body, forcing overlying strata to bulge upward.
[1875–80; < Greek lákko(s) pond + -lith]
lac`co•lith′ic, lac`co•lit′ic (-ˈlɪt ɪk) adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


A lens-shaped mass of intrusive igneous rock that pushes overlying rocks into a dome.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited
References in periodicals archive ?
and Holdsworth, R.E.: 2016, Deformation structures associated with the Trachyte Mesa intrusion, Henry Mountains, Utah: Implications for sill and laccolith emplacement mechanisms.
(2003) record saponite as the main phyllosilicate in the contact between the marl-limestone rhythmite and doleritic laccolith of Sierra de Priego (Cordoba), as a consequence of a late hydrothermal process after contact metamorphism produced by the intrusion of subvolcanic rocks.
Johnson & Pollard (7) recognise that laccolith formation is characterised by three distinct stages.
"The 'bun' may be the result of what is known on Earth as a laccolith, an intrusion formed by magma pushing up from below.
Whilst he was in fact describing an actual geological feature--a laccolith which he saw as resembling a cactus [1]--he was also, tongue-in-cheek, commenting on what he saw as an absurd number of "-lith" words in the field of Geology.
Some geologists believe Devils Tower began as a laccolith, a buried intrusion of igneous rock; others say it is a volcanic plug, the leftover spout of an extinct volcano.
Ongoing field mapping of Cretaceous sedimentary rocks has identified numerous intrusions that appear to be cross cut by Laramide and post-Laramide deformation in the South Persimmon Gap Laccolith (SPGL) and Dagger Mountain areas.
Kelsey-Fry (still representing Fallon) observes that Murrihy "opined", a word that, along with rostral and laccolith, you very rarely hear.
It was probably a laccolith that was exposed by erosion and tectonic uplift, evidenced by the occurrence of a fault line a few kilometers from the site.
The country rock in the district consists of Cretaceous thinbedded limestones and shales that have been injected with felsic eruptive rocks, the largest mass of which is the granodiorite laccolith forming San Pedro Peak near the center of the property.
and Radon, M.: 2000, Tertiary phonolite laccolith of Marianska hora Hill, N Bohemia: Geological, petrological and mineralogical characteristics, Acta Montana, ser.