IntroductionAxial Seamount rises 700 m above the mean level of the central Juan de Fuca Ridge crest about 480 km west of Cannon Beach, Oregon to within about 1400 m of the sea surface. The volcano is the most magmatically robust and seismically active site on the Juan de Fuca Ridge between the Blanco Fracture Zone and the Cobb offset. The summit is marked by an unusual rectangular-shaped caldera (3 x 8 km) that lies between two rift zones. The caldera is breached to the SE and is defined on three sides by boundary faults of up to 150 m relief. Hydrothermal vents colonized with biological communities are located near the caldera fault or along the rift zones. Following the discovery of hydrothermal venting north of the caldera in 1983, a concentrated mapping and sampling effort was made in the mid-late 1980s. An eruption was detected seismically in January 1998; later mapping revealed a lava flow erupted from a 9-km-long fissure at the southern end of Axial caldera. The new lava flows were seen to partially bury a seismometer/ pressure gauge and mooring line deployed in 1997.
Smithsonian / GVP volcano information
See also: Sentinel hub | Landsat 8 | NASA FIRMS