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Volcanic arc identification and geology
A curved chain of volcanoes formed above a subduction zone, positioned on the overriding plate approximately 100–300 km from the trench. Volcanic arcs are produced by partial melting of the mantle wedge above the subducting plate, triggered by the release of water from the descending slab. Arcs can be oceanic island arcs, e.g., Japan, Aleutians or continental e.g., Cascades, Andes . Field: volcanology. Example: The Cascade volcanic arc from British Columbia to northern California includes major volcanoes such as Mount Baker, Mount Rainier, Mount St. Helens, and Mount Shasta, all generated by the subduction of the Juan de Fuca plate beneath North America.. Related terms: Subduction, Island arc, Andesite, Magma.
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
- 2026-03-30T15:19:42.096023+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.
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