9: Realities

East Pacific Rise

The decision to dedicate an Alvin dive to explore an unknown area is not one that can be made lightly. As I've written earlier, just getting this cruise to go has literally taken years, and that is not counting the time it took to write the proposal to request funding from the National Science Foundation. During each step of the way, I have remembered the myriad of things that I know about that can affect cruises, even those led by the most experienced scientists. Weather limits Alvin diving, as it can very easily become unsafe for the swimmers who have to enter the water to secure Alvin and its basket before it begins its descent and after it rises from the bottom at the end of a dive. Alvin itself isn't the only problem swimmers might encounter; they face the liability of getting in the middle of a close contact between the 23 ton Alvin and the ship.

Technical problems that might handicap the sub, its ability to work or to sample all can affect the success of a dive, regardless of whether the site is well known or entirely new. The amount of high-tech electronic gear that runs Alvin is incredible and if seawater seeps in, a readily envisioned event at the bottom of the ocean where hydrostatic pressures are so immense to be unfathomable to me, the possibility is very real.

This type of concern is always in the back of my mind as I consider dive targets, especially as I think of the people on board who have yet to dive and, if something comes up to interfere with dive operations, will not get to go. On exploration dives, a key factor in determining who goes to the seafloor is who has the expertise I think I will need to have on-site so the decisions that have to be made by the divers without consulting those of use left behind on the ship can be made. A person who has never dived before is less equipped to make those decisions, as everything in Alvin is new to them. However, we aren't out here to give people rides in the sub. We are here to document the animals that live on the seafloor, and to do it as completely as possible, regardless of who goes.

Once one decides to make one exploration dive, it is very easy to choose to make two dives in the same area. Perhaps this is as close as I have come to displaying a gambling obsession. Once I have invested a dive in an area so we know something about it, knowing just a little more would be better, and when we know where something isn't, it's easy to figure it must be were we didn't look yet. So for me, one dive into the unknown can be easily justified to become two. That's the way it turned out in our last exploratory area, except two became three. Images of glassy basalt flows, bacterial mats, biological collections and snow blowers that returned with the first dives to this area are very similar to those from other spreading ridge sites that had had recent volcanic eruptions. The snow blowers aren't the type you need in winter in Chicago, they are places where the fluid rising from beneath the seafloor carries with it so much bacteria that it looks as if you are in a blizzard. These observations on our first dive at this new site were enough to get me hooked that we could find something worthwhile were I chose to dive there again, and again.

What we found? More glassy basalt, new species of polynoid worms and blobs of mucus. I am delighted to say that my crack biology team sorted an estimated 9 gallons of mucus that were collected during these three dives. We didn't find giant tube worms, giant clams or anything bigger than a house fly, but we did perhaps find what is among the newest vents on the spreading ridge. How old are they? Younger than the century according to my geology colleague. Personally, I think that they are younger than that, but I'm not arguing as I feel that my gamble paid off.