Our final log of the black smoker expedition is a "guest" log. It comes from Margaret Carruthers, research assistant at The American Museum of Natural History. See the Who's Who section for more information. It is written to Kate, another member of the Earth and Planetary Sciences Department at the Museum:

Dear Kate,

Thanks for the note and for taking care of things for me at the Museum, and sorry for not keeping closer in touch. I have been super busy.

Mosaic of an active chimney

Mosaic of sulfide structures

We had a lot of data to mess with from the Jason dive last week. I have been working on creating mosaic images of the S&M structure, learning a new mosaic program, and teaching everyone else how to do it. Our Jason dives were separated by the ALVIN program just for this reason- so that everyone could work up the image and navigation data and figure out better ways to go about collecting the data for the next dive. The images for S&M are quite good, but unless Jason's heading and pitch are the same for a whole sequence of images, it's difficult to piece them together without severely distorting them. In addition to 8 cameras, Jason also has a sonar system that can measure topography of a surface in front of it. The sonar scans back and forth and can have as good as 1 cm resolution. That is, we can determine the shape of the surface of the sulfide structures to an area of 1 cm. Dana Yoerger, one of the engineers from Woods Hole has been able to take the sonar data and make topographic profiles and surface maps of the structures. This is not an easy task. It took about 3 days of messing with the data and writing programs to display it correctly. We are hoping to be able to take the mosaics and overlay them onto topography for a three-dimensional representation of the structures. I think it will be possible on a small scale, that is, we can probably overlay a mosaic of a single side of a smoker. But whether or not we can mosaic different sides of the structure together is another matter.

Mosaic of fractured basalt

We've put Jason in the water again. This time we are in the Mothra region, which is south of the Main Endeavor Field (MEF--where S&M is) and not as well explored. Debbie Kelley and John Delaney went down there in ALVIN a few days ago. The Mothra region has a very different character from the MEF. In the MEF, the structures are fat and columnar, with many flanges. Flanges are mushroom-head shaped structures that seem to grow out from the sides of the smokers. But in Mothra, most of the smokers are spires or pinacles without flanges. We are in the process of very carefully gathering images and topographic data of the spires. We imaged in a forward-looking mode, that is, with most of the cameras looking forward, for the first of the Mothra dives. Then we recovered Jason and remounted the cameras and sonar to look downward. This will give us the much-needed detailed plan view of the area. We have nearly, if not completely full coverage of the area now.

Smoking flanges

"I'm Not A Crook" sulfide structure

There are two great pastimes other than evicting worms from their tubes that perhaps Ed didn't tell you about. The first, coloring styrofoam cups and wig-heads is done late at night, before an Alvin dive. You might never think that styrofoam cups would make an interesting present, unless of course you could present them to someone who'd never seen or conceived of them before, or maybe if they had a really good drink inside. Even then, I don't think they'd be too exciting. But after their journey to the bottom of the ocean, they become beautifully contorted espresso cups or shot glasses. I'll bring one back for you.

The other activity is marine ping-pong. As you can imagine, the game is much different from the terrestrial version. As the ball maintains its course, the table and net do not. I've never thought of ping-pong as much of an aerobic sport, but when the ship rolls 25 degrees and you have to run three steps to the ball, you're really running 3 steps uphill, or flying 3 steps downhill. It's quite invigorating. If you master this, challenge can be added by playing while the floor drains are hiccupping up dirty water, vent fluid, and red tubeworm dye, allowing you to attempt the downhill and cross-country ski versions of ping-pong.

I hope everything is well at the Museum. We'll be back next week.

Before the Dive

After the Dive

Margaret