Built by a geologist
Intrusive identification and geology
Describing igneous rock that crystallized from magma below the Earth's surface, enclosed within pre-existing country rock. Intrusive rocks cool slowly, allowing large mineral crystals to develop, resulting in a coarse-grained phaneritic texture. Common intrusive rock types include granite, granodiorite, diorite, gabbro, and peridotite. Intrusive bodies include batholiths, stocks, sills, dikes, and laccoliths. Field: petrology. Example: The Half Dome pluton in Yosemite National Park is an intrusive granodiorite body that crystallized several kilometers below the surface approximately 87 million years ago and was subsequently exposed by millions of years of uplift and erosion.. Related terms: Extrusive, Plutonic, Phaneritic, Batholith.
Sources, scope & corrections
These authoritative resources support category-level nomenclature, terminology, identification methods, and safety. When a specimen-specific safety warning appears, the public-health source listed here directly supports that precaution. They are not line-by-line citations for every other property on this entry, and natural specimens vary.
- Editorial owner
- GeoMiner
- Last updated
- 2026-03-30T15:19:42.027557+00:00
- Review status
- Published; not independently peer-reviewed
- USGS Thesaurus — U.S. Geological Survey. Controlled earth-science terminology used to describe USGS information resources.
- Glossary of Geologic Terms — U.S. National Park Service. Geologic definitions prepared by the NPS Geologic Resources Inventory.
Read GeoMiner's editorial methodology or report a content issue.
JavaScript is loading the interactive GeoMiner experience. The identification tools provide educational candidates, not laboratory confirmation.