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An igneous rock composed predominantly of plagioclase. Lunar anorthositic rocks are central to the flotation interpretation of the lunar magma ocean. Their mineral and chemical composition does not alone date the formation of the complete crustal layer; sample context and radiometric dating are needed.

A large igneous province is a geographically extensive accumulation of igneous rock emplaced in unusually large volumes over a comparatively concentrated geological episode. Surface lava flows can be accompanied by substantial dikes, sills and deeper intrusive material, so mapped lava area alone does not measure the total magmatic addition.

Its physical effects depend on emplacement rate and environment as well as volume. Rapid gas release can alter atmospheric composition, and intrusions can heat surrounding volatile-bearing rocks. The Siberian Traps and Deccan Traps illustrate why eruptive chronology, intrusive volume and gas production must be measured separately when testing environmental consequences.

A body of igneous rock crystallized from magma emplaced beneath the surface. Granite is a common plutonic composition. A pluton's gravity anomaly depends on its geophysical density contrast and geometry, rather than on the rock name alone.