Cobb hotspot

The Cobb hotspot is a volcanic hotspot located 460 km (290 mi) west of North America in the Pacific Ocean. The hotspot is at the Juan de Fuca Ridge, and has made the Cobb-Eickelberg Seamount chain. The Axial Seamount is the hotspot's most recent eruptive center, which last erupted in 1998.

The central ridge is thicker than the surrounding crust by one to two km and may be accumulated buildup from the hotspot, which is essentially an underwater volcano with a root twenty to forty kilometers in diameter reaching a depth of 11 kilometres (6.8 mi) beneath the volcano. The magma flows at rate of 0.3 to 0.8 m³/s. The caldera is 1,450 metres (4,760 ft) below sea level.