Posted by graduate student Alison Sipe, University of Delaware College of Marine Studies.

The science party just filtered out of the library at the conclusion of the nightly meeting. The meetings are critical for the group to reflect on the research objectives and plan their Alvin dive strategies. The library was packed with people, some of whom were fortunate enough to find an open chair.

Dr. Anna-Louise Reysenbach, one of the two science observers in Alvin today, briefed the science party on the very successful Alvin dive. The sub reached the ocean bottom at 0921 hours. The submarine pilot, Patrick Hickey, navigated Alvin to a prominent chimney feature called Rebecca’s Roost. Here the divers discovered many vent clams and huge microbial mats (massive flat colonies of marine bacteria) that were intertwined with loads of Riftia tubeworms. They collected interesting chimney features referred to as “flanges.” These are bulbous chimney formations that jut out from the main rock structure. Super-hot water seeps slowly out of the rock and lingers under these flanges, forming a pool. This is a perfect spot for vent bacteria to live because the water motion is not fast and furious, but rather the metal-rich hyperthermal water is delivered to them gently and constantly. It’s sort of like bathing in a jacuzzi instead of a geyser. Microbiologists on board worked with the sulfidic flange samples throughout the night looking for signs of life within or on these rock features.

Donald Nuzzio, the starboard observer in Alvin, successfully measured the electrochemistry of water samples in situ (“in the natural environment,” rather than collecting water in a container and making the measurements later). He collected over 230 measurements, which sounds like a lot of work, but is all in a typical day for this chemist. The submarine also collected about fifteen Riftia tubeworms, two massive twig-like networks of black branching coral, and several other polychaete worms called Paralvinella. Paralvinella looks like it is wearing a coat of fur, but these hair-like projections are actually strings of vent bacteria that are hanging on for a ride. Some hydrothermal vent microbiologists study the physiology of these bacteria and are trying to learn the details of this symbiosis (sym = together, biosis = to live).

The Alvin pilot uses sonar to locate prominent vent structures. The locations of some of the features are well-known, such as Rebecca’s Roost and Everest. When Alvin discovers new rocks and chimneys, the pilot measures their locations with very specific X-Y coordinates so that the feature can be relocated in subsequent dives. The people in the submarine are lucky enough to name the chimney. Descriptive names of some other chimneys include Faulty Towers, Tubeworm Pillar, and Godzilla.

It was a busy night for the scientists in their laboratories aboard the R/V Atlantis. A successful Alvin dive means lots of work for the researchers. The group was thrilled to have such spectacular vent specimens. The scientists teemed with energy while at the same time maintaining their concentration in the labs.

It was an action-packed day, and it is not yet over. The cruise ping-pong tournament began today. A sign hanging over the galley announced “Let the Games Begin!” As I conclude this journal entry, I will play my first match of the tournament against Patrick Hennessey, one of the ship’s crew with a true reputation on the ping-pong table. I've been fine-tuning my serve, but don’t think it will help me much in this match-up. At least I can look forward to the consolation round.