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These animals all glowed, Lee recalled days later."Everything is fluorescent down there," she said. "They're tiny, and they're weird. They're not big fish, just weird sorts of organisms, and kind of transparent. It was really cool."
Not that she had much time for sightseeing. As Alvin slowly "drove" up a Hess Deep slope, Lee spent four hurried hours dictating, photographing and writing non stop, barely finding time to bite into her lunch - a peanut butter and jelly sandwich.
She also recorded navigational coordinates for Karson while Hickey manipulated Alvin's robot arms to collect rock samples as the submarine maneuvered past gabbro rocks that might have formed atop a reservoir of hot magma.
Lee also vividly remembers her initially wild, later boring, ride into the depths.
"After that, you have an hour to get used to it. You can't see anything outside after a while, and there is nothing for you to do, and the pilot isn't doing anything either. So Jeff slept, and I kind of sat there.
"Then you get down and all of a sudden it's like going 300 miles an hour. You have to constantly be recording pictures, recording the samples, recording geocompass data. I had no idea it would be so busy down there. You have to make the most of your time. The next thing you know, it's time to come up."
Because Karson sat in the port (left) position, "Jeff really was in charge of most things," she added. "He had to control all the cameras. I can't imagine being the port observer, because there is so much to worry about." During much of the trip, her own starboard (right-sided) viewing position faced open water rather than the rock face. That meant Lee had to monitor a video screen to keep up with the real action on the vessel's other side.
Before the Hess Deep expedition's start, Lee had spent some of her time gathering and copying videos of Karson's earlier 1990 Alvin dives to Hess Deep. Slightly more than a week after boarding Atlantis, she began computer-merging individual digital images of Hess Deep made by the still-underway and highly successful Argo II remote camera survey.
But Lee found neither past Alvin videotapes nor current Argo II photo composites compared with her view from Alvin. "It's amazing how different it is from looking at these pictures or videos," she said. "You're in an awkward position looking out the window at a weird angle, but it's crystal clear out there.
"After a while you'll forget, and you'll think that you're looking at a video. And then, this fluorescent fish will glide by."
With some 15 minutes of bottom time remaining after Alvin's collection baskets were completely loaded with rocks, Hickey and Karson let Lee take over Alvin's joystick controls. "That was awesome," she recalled. "The pilot's view is a million times better than the port or the starboard observers'. I got to see more while doing that than probably the rest of the time.
"It's amazing how responsive the controls are," she said. "You only need to turn it a tiny bit." As Lee worked the joystick, Alvin was still passing by rock outcrops. So "I was still talking into my recorder and describing them," she added.
Soon Lee could tell that Alvin was moving above the gabbro area. She knew because she began spotting dikes, the ancient channels through which magma once coursed upward toward the ocean floor when their dive site was miles west on top of the East Pacific Rise.
That's when Hickey told her to stop driving and pull the switches that ordered Alvin to drop several 200-pound weights. The loss of that load increased the submarine's buoyancy enough to start it on its rise towards the surface.
"By that time you're pretty uncomfortable and kind of want to get out of there," she said. Condensed moisture had made everything clammy, and Lee was cold despite the cotton pants, three shirts and two pairs of socks (one of them wool) that she wore as diving clothes.
On the way up, she and Karson took turns stretching cramped legs in the only part of the postage stamp cockpit where they could stand up. Then, as Alvin finally bobbed to the surface and flipper clad swimmers splash-boarded the sub's tiny deck from the Avon motor launch, the sudden pitching in three dimensions made her feel a little seasick.
"I had to close my eyes," she said, "because if you opened them everything was moving in all different ways. So you see the swimmers outside the window and you're like: 'Okay, come get us!' It's about 5 [p.m.] when you get out, and you've been in there since 8 a.m. That's a long time."
While Alvin dive time is a coveted opportunity for a master's degree graduate student, Lee spends most of her time aboard Atlantis behind a computer screen - work she will continue all summer and beyond when she returns to Duke.
The combination of Argo II and computer mosaicking is the equivalent of draining the Pacific to expose its floor to bright sunlight, flying down two miles in a helicopter to take telephoto pictures of the Hess Deep's canyon's sloping north wall, and then combining the photos to make a wall chart.
After a challenging learning period, she and other Hess Deep team members have gotten extremely good at making the sometimes reluctant software programs work. In fact, Lee brought along an Argo II photo mosaic of her own dive area when she went down in the Alvin.
Unfortunately, she was never able to match up any identifying landmarks. She may just not have had enough time, she said.
"I'm not a computer person," Lee noted. "But I like this because it's not numbers, abstract modeling, or anything like that. This is a very visual sort of activity, and the computer does a lot of it for you."
Steve Hurst, a Hess Deep co-principal investigator from the University of Illinois at Champaign-Urbana (and a former Duke research scientist), said the Argo II mosaicking uses two principal computer graphics programs: Videobrush and I/RAS-C.
Mosaickers usually first employ Videobrush, a tool that is "supposed to blend together pictures that overlap a lot to get a higher resolution," said Hurst, who has also made the use of computer graphics in geology one of his specialties.
"The Videobrush program is easier and quicker to use - when it works," he added. "Usually we put together at least a few images in Videobrush. It lets you try and blend up to nine images, but I'm happy to get three or four."
I/RAS-C "is much more manually oriented" than Videobrush, Hurst continued. "Videobrush is completely automatic. The positioning of light to dark areas is all it knows about. In I/RAS-C, you have to select the matching part of each image. We can tell what is a rock and what is not. Videobrush guesses, and if its guess is wrong we can't do much about it."
Of the two, then, it is I/RAS-C that makes use of human's superior abilities to make sense of subtle forms and relationships in nature. But I/RAS-C is "a complicated and very unforgiving program," he said. "The less we do in Videobrush, the more we have to do in I/RAS-C. And while I/RAS-C gives nice, high-quality results, it takes longer."
Like prize-winning art objects, the most startling photomosaic composites are beginning to be displayed on the walls of Atlantis's computer room and Argo II control van. One, by Hess Deep scientist Gail Christeson of the University of Texas at Austin, took about "six to eight hours" to complete - "not all at one time," she said..
It shows two dikes, the fattest about six feet wide, both tilted at off-vertical angles. Between the dikes, and beyond them on each side, are rubbley intermediate spaces festooned with fist-sized and larger rocks. A composite of about 40 separate images that Argo II photographed in about six to eight minutes, the montage covers about a 26 by 66 foot swath of a sloping Hess Deep escarpment, Hurst estimated.
Like Lee had earlier, Christeson made the montage before her own Wednesday, March 31 dive to the same area with Texas A&M researcher Jay Miller, then took it down with her. While she couldn't recognize the site down below, "Jay thought he might have seen it," she said afterwards.
Karson, the Hess Deep chief scientist, described the mosaicking results in one word: "Fantastic!
"This is one of the things that we came out here to do, and we've been able to do it very successfully; so we're really happy with this part of the project," Karson said shortly before going down in Alvin today, the feast of Passover, with Duke senior Aisha Morris.
"It's giving us an unprecedented view of the structure of the oceanic crust," he added. "It is really helping us revise everything we thought about what the upper oceanic crust is like. It especially shows how widespread the faulting and fracturing and tilting of dikes have been. And it also gives us a feeling for the lateral continuity of the outcrops, the spacing of dikes, and things of that nature."
Standing nearby on Atlantis's aft main deck while Alvin was getting final preparations for another mission, Bob Varga, a Hess Deep researcher from the College of Wooster in Ohio, had similar praise.
"I think the imaging of the third dimension in the ocean crust, like we're doing here along the wall of Hess Deep, is the most innovative thing about this entire cruise," Varga said. "The ability to clearly see wide swaths of cross sections across the ocean crust is certainly the thing that has impressed me the most."
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