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Coordinates: 44°23′57″N 121°52′17″W / 44.3992857, -121.8714477
Hayrick Butte is a tuya volcano in the Cascade Range of northern Oregon, located near Santiam Pass just west of the Cascade Crest. It is adjacent to the cinder cone, Hoodoo Butte, which overlaps its western edge.
A tuya is a type of subglacial volcano, formed when lava erupts underneath an overlying glacier or ice sheet and then melts through to the surface and pools, producing the flat plateau on top with near-vertical walls along the ice-contact margin as the lava cools and hardens. Hayrick Butte is one of the most perfectly formed examples of a tuya in the contiguous United States with a nearly flat triangular plateau about 0.5 miles (0.8 km) across and steep walls rising about 700 feet (210 m) above the plain below.
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