Anahim hotspot
 Anahim hotspot (British Columbia)
Location of the Anahim hotspot in British Columbia
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| Country | Canada |
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| Province | British Columbia |
| Region | Interior Plateau |
| Coordinates | 52°56′N 123°44′W / 52.93°N 123.73°WCoordinates: 52°56′N 123°44′W / 52.93°N 123.73°W—Nazko Cone |
| Last eruption | 7,200 years ago |
The Anahim hotspot is a volcanic hotspot located in the West-Central Interior of British Columbia, Canada. One of the few hotspots in North America, the Anahim plume is responsible for the creation of the Anahim Volcanic Belt. This is a 300 km (190 mi) long chain of volcanoes and other magmatic features that have undergone erosion. The chain extends from the community of Bella Bella in the west to near the small city of Quesnel in the east. While most volcanoes are created by geological activity at tectonic plate boundaries, the Anahim hotspot is located hundreds of kilometres away from the nearest plate boundary.
This hotspot's existence was first proposed in the 1970s by three scientists who used John Tuzo Wilson's classic hotspot theory. This theory proposes that a single, fixed mantle plume builds volcanoes that then, cut off from their source by the movement of the North American Plate, become increasingly inactive and eventually erode over millions of years. A more recent theory, published in 2001 by the Geological Society of America, suggests that the Anahim hotspot might be supplied by a mantle plume from the upper mantle rather than a deep-seated plume proposed by Wilson. The plume has since been tomographically imaged, showing it to be roughly 400 km (250 mi) deep. This measurement, however, could be an underestimate as the plume might originate deeper within Earth.
Volcanism as early as 14.5 million years ago has been linked to the Anahim hotspot, with the latest eruption having taken place in the last 8,000 years. This volcanic activity has produced rocks that show a bimodal distribution in composition. While these rocks were being deposited, the hotspot coincided with periods of crustal extension and uplift. Activity in modern times has been limited to earthquakes and volcanic gas emissions.
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