Teacher Logbook:
Monday, July 3, 2000 1800 hrs.

ROPOS spent last night investigating a hydrothermal vent at South Cleft. Early this morning I watched the action from the ROPOS control room. The vent stood about 16 meters tall (over 50 ft.) and had multiple chimneys. It spewed forth a black cloudy fluid; hence the name black smoker. The "smoke" is actually superheated water with sulfides and sulfates in dissolution. These compounds either precipitate out creating the towering chimney or are ejected into the cold oxygenated ocean water forming a plume. Temperatures up to 327°C (621°F) were measured here in 1995. In contrast, the surrounding ocean bottom water averages only 2°C or 3°C (36°F). It's like getting in the shower and not being able to find the right temperature.

ROPOS collected various samples and placed them into the "bio-box". Upon return, a few of the scientists were waiting on the fantail of the ship like a kid on Christmas morning. Samples included some dead tube worm casings covered in sulfides, a few species of other worms, and part of a sulfide chimney. Everything was placed in buckets and taken into the lab.

One of the more interesting things brought up was a small section of wood that was left during last year's expedition. In only one year it had several types of worms growing on it and tiny clams that bored their way into the softened 2x4. After talking to a few scientists I learned that the critters on the wood were benthic (bottom dwelling) animals specializing in making a living on wood. That's their habitat. It blows me away to think there are creatures, that are adapted for wood, at the bottom of the ocean. There's a niche for everybody.

After exploring the vent, we put ROPOS on deck and took the 6 hour journey to Axial Volcano for our next dive. Check us out tomorrow for an update from the Axial Volcano Hot Spot.

Jeff

Small section of wood left one year ago on the bottom, now encased with small worms and clams.
(7/3/00 ROPOS)