Basalt rock being collected by Tiburon's mechanical arm on Davidson Seamount off California.
Photo © 2000 MBARI
Sheet flow at President Jackson Seamounts, which have complex, nested calderas.
Photo © 2000 MBARI
Intraplate seamount volcanism is of different types
Many chains of seamounts (submerged mountains) are of hot spot or subduction arc origin. However, some intraplate seamounts have different origins. Near-ridge seamounts erupted near the axes of mid-ocean ridges onto recently derived oceanic crust. In the north-east Pacific, these include the Vance and President Jackson seamounts near the Juan de Fuca and Gorda Ridges, respectively, and the Taney Seamounts off San Francisco, which are no longer associated with an active spreading center (map, 50 kb). Some isolated seamounts and other linear seamount chains have erupted onto much older oceanic crust, and their formation is enigmatic: they do not appear to have erupted as hot spot volcanoes or near-ridge seamounts, and they are not associated with subduction processes. Examples of these include Davidson, Pioneer, and Guide seamounts (map, 118 kb) near the California coast, and the Line Islands chain in the middle of the Pacific Ocean. Note that our work at Axial Seamount is covered in the Mid-ocean Ridge section.
Monterey Bay Aquarium's Mission to the Deep exhibit features a mission to map Davidson Seamount
From our group's expeditions to NE Pacific seamounts:
- MBARI YouTube video of coral-eating sea stars
- MBARI YouTube video about Davidson Seamount
- Seamounts 2007 cruise logbook
- Vance 2006 cruise logbook
- Seamounts 2004 cruise logbook
- Seamounts 2003 cruise logbook
- MBARI news story about seamounts off Southern California that were ancient islands
- USGS newsletter about Seamounts 2003 expedition
- NOAA website about Davidson Seamount 2002 expedition
MBARI has mapped many of the near-ridge and continental margin seamounts off of the west coast of North America with high resolution multibeam sonarQuestions? Comments? Please contact Jenny Paduan