laccolite Geol.
(ˈlækəlaɪt)
[f. Gr. λάκκο-ς a reservoir + -lite. So named by Gilbert in 1877.]
A concordant mass of igneous rock thrust up through the sedimentary beds, and giving a dome-like form to the overlying strata.
| 1877 Gilbert Rep. Geol. Henry Mts. ii. 19 For this body the name laccolite..will be used. 1896 Pop. Sci. Jrnl. L. 241 These are connected..with Plutonic plugs, laccolites. 1937 Wooldridge & Morgan Physical Basis Geogr. viii. 110 Laccolites are closely related in manner of origin to the stratiform intrusions of igneous rock..termed ‘sills’. 1946 L. D. Stamp Britain's Struct. ix. 80 A special type of sill is one where the lava swells out to form a lens-shaped mass—which according to its particular form is known as a laccolite (with a flat base) or a phacolite (with a curved base). |
Hence laccoˈlitic a., pertaining to a laccolite.
| 1877 Dutton in Gilbert Rep. Geol. Henry Mts. 69 Laccolitic nuclei. 1879 Nature XXI. 179 It is not likely that the Henry Mountains are the only ones constructed on the laccolitic type. |