A rock formed by crystallization of magma or lava. Intrusive bodies crystallize below the surface, while extrusive rocks solidify at or near the surface. Granite is a common intrusive example and basalt a common extrusive example.
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.
Articles by others on the same topic
There are currently no matching articles.