Dive Areas
All five dive targets on the East Pacific Rise may host vent fields. During Janet’s last cruise here in December, 2002, a plume of hydrothermal fluid was detected in the water column near 8° 37'N, a spot where earthquakes had been detected in March, 2002. (For more information, read a dispatch from last year’s East Pacific Rise expedition.) This year’s expedition will explore this area to try to document active venting.
Three other areas targeted for dives --9° 50'N, 11°, and 13°N--host known hydrothermal activity. Fluid collections, biological collections, and the recovery of experiments left on the seafloor a year ago are goals for these areas. At the fifth area near 15° 42'N, a survey of chemical signals in the water column found evidence of an active but undiscovered vent field. This site is nearly intermediate between two known vent areas, each with a slightly different fauna. Collections from a new vent field here would help document differences between the fauna in the two known areas.