Plutonic landforms

Concordant bodies

Intrusives that follow the bedding of the strata they intrude.
Conforms to the normal; does not deform or disrupt strata.

Discordant bodies

Intrusives that does not follow the bedding of they strata they invade.
Cuts across rock layers.

Sill

A tabular igneous body formed when magma is injected along sedimentary bedding surfaces.

Laccolith

Relatively small, mushroom-shaped pluton that forms when magma intrudes into parallel rock layers close to Earth's surface.
Blister-shaped.

Phacolith

Lens-shaped masses seated in anticlinal crests and synclinal troughs.
They extend along the direction of anticlinal and synclinal axes and are elongated in plan view.

Lopolith

A large, lenticular, centrally sunken mass of igneous rock whose surfaces are concordant with the enclosing rocks.
Shape like a champagne glass.
Usually gabbroic in composition.

Dike

A slab of volcanic rock formed when magma forces itself across rock layers.

Cone sheet

Dikes that radiate from a central supply point.

Bysmalith

Popsicle-shaped.
Developed when highly viscous magma is injected. Moves upward because the lateral spreading along bedding planes is less.

Batholith

Large mass of intrusive igneous rock believed to have solidified deep within the earth.
Largest intrusive.
Thin and mainly intermediate-felsic in composition.

Stock

Smaller version of batholiths. Sometimes connected to them.
<100km2 of surface exposure.

Chonolith

An intrusive igneous rock mass of wholly irregular form.