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Le Olson (in yellow hat) brings the Roane chimney
aboard.
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20,000 Pounds of Tension
by Peter Tyson
July 8, 1998
The tension in the air was arguably as great as that on the
line. And considering the tension on the line had just reached
8,000 pounds, you can imagine the kind of tension in the air
I'm talking about.
It was 10:45 this morning, and we were back on the fantail of
the Tully. As it turned out, we were on the brink of
recovering a second black smoker chimney, although it didn't
look quite so positive at the moment. The yellow line was taut
as a high wire; clearly it was fixed fast to Roane, as
John Delaney
had dubbed this chimney. But even at 8,000 pounds of tension,
it hadn't succeeding in breaking the chimney free from its
moorings. Would Delaney's gamble to attempt removal without
using the chainsaw pay off? Or would Roane refuse to let go,
effectively anchoring us to the seafloor?
Wearing a look of concentrated concern,
Le Olson,
the engineer from the University of Washington's Applied
Physics Lab who's in charge of recovery operations, kept his
eye fixed on the tension gauge on the FADOSS. Vaguely
resembling a Dr. Seuss contraption, the Fly Away Deep Ocean
Salvage System was a pea-green machine with large flywheels
that routed the incoming yellow line this way and that until
it spilled out the back, where the Tully crew fed it into a
basket. At the center of the machine lay what looked like an
oversized bike pump. This was the compensator, which was now
coping with the tension the winch was using to try to break
Roane free.
The gauge climbed to 10,000 pounds. Vern Miller, Olson's
associate, raised two hands with his fingers splayed to convey
that figure across the fantail. He was smiling, which I took
to be a good sign. Perhaps, despite Olson's pensive
expression, this was par for the course. I couldn't ask
anyone, because the winch engine was once again roaring to
beat the band, and everyone either had foam plugs jammed into
his ears or wore those big headphone-like mufflers. All I
could do was smile stupidly at people in the know and try to
read their lips as they yelled to other people in the know.
John Delaney inspects Roane aboard the CCGS John P
Tully.
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I did know that there were two key differences between Roane
and Phang, the chimney we pulled up three days ago. For one
thing, unlike Phang, Roane was alive. It was no smokestack,
with the kind of billowing black smoke that gives these
chimneys their name. But it was decidedly active, with diffuse
plumes of superheated water shimmering up its flanks. We
measured those plumes last night using ROPOS. They reached
176°F, and that's amidst 35°F sea water. So you can
imagine how hot Roane must have been on the inside. Roane's
activity affected our attempt in two ways. First, active
chimneys are structurally weaker than inactive ones, and thus
Roane might break apart like a wet sandcastle. Second, if the
superheated water inside flashed to steam on the way up, the
force of the water's expansion, which can be as much as 100 to
one, could also threaten to shatter the structure.
The second difference was that Roane was bigger than Phang.
Much bigger. Size does matter when you're lifting heavy
objects off the seafloor. Phang weighed about 1,200 pounds out
of water. Estimates for Roane out of water, if we succeeding
in retrieving the whole shebang, were on the order of 7,000
pounds.
At ten of eleven, Vern Miller raised two hands, then one hand:
15,000 pounds. He had stopped smiling. Everyone else looked
either anxious or affectedly not. Even if it hadn't been for
the clamor of the winch, I think silence would have reigned.
My eyes flashed between my watch and the tension gauge.
10:54 a.m. 17,000 pounds.
A small crowd of people stood high above the fantail. They,
too, wore earplugs or mufflers, and looked anxious or
affectedly not. I risked disturbing Miller by yelling into his
ear, "What's going on?"
He yelled back, "It's just not breaking. Right now, we're
attached to the whole thing." He meant the wide base of the
chimney, not just the spire we were after. But he might as
well have meant the ocean floor.
10:58 a.m. 18,000 pounds.
The gauge went to 65,000 pounds, so this was probably small
potatoes for it. But the winch was rated at 30,000 pounds and
the A-frame at 28,000 pounds. We were starting to push the
envelope.
At 11:00 precisely, the gauge tipped past 20,000 pounds. Olson
waved Delaney into the relative quiet of the lab. I followed,
along with four or five others. Olson began to suggest the
alternatives: slack off and reload; hold tension for awhile
longer; or cut the line. I was just beginning to wonder if
Delaney was regretting his decision to forgo the chainsaw when
Miller burst into the room.
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Expedition co-leaders Ed Mathez (left) and John
Delaney head to the Tully for the attempt on Roane.
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"Le, I think it just broke!"
Everyone dashed outside. The gauge read 15,000 pounds and was
going down fast.
The mood on deck did a back flip. Frowns became grins,
tentative touches on shoulders became thunderous pats on the
back. With the winch still precluding speech, Olson grabbed
the arm of
Ed Mathez,
mouthed the words "Got something," and flashed his trademark
grin. I could see waves of relief washing over both Delaney
and
Deb Kelley.
Olson later told me simply, "Spirits soared."
We didn't know what we had; we only knew the chimney had given
way. The FADOSS compensator had locked up, so it was
impossible to know how much it weighed. How big was it? Did we
get all of it, or some of it, or none of it? The complete loss
of Roane was possible, but the general mood seemed to sweep
such concerns aside.
In Scottish Highland folklore, Roane are seals that are
actually fairies who dress in sealskins so they can pass
through water. They are the kindest off all fairy people,
because they never avenge themselves of the people who hunt
them. (I know this from the book Abbey Lubbers, Banshees, and
Boggarts: An Illustrated Encyclopedia of Fairies, by Katharine
Briggs, which somehow got onto this ship and has provided
names for one or two chimneys.)
Well, Roane the chimney did not avenge itself of its captors
by shattering or vanishing altogether in the depths. Instead,
45 minutes after the winch wrenched it free, Roane rose out of
the ocean at the stern of the Tully. As we had expected, the
unsupported cone was missing, and what came up was in two
pieces. But a good 4,050 pounds of chimney, solid as a redwood
and still smoking, was lowered onto the deck.
Delaney and Kelley rushed forward and plunged a temperature
probe into the smoking orifice. It registered 194°F, and
that was after an hour in near-freezing water and another half
hour in cool air. I stuck my hand in the fist-sized opening;
it felt like a sauna in there. Such heat helped give life to
the forest of straw-like tubeworms clinging to the chimney's
sides. A black mineral, which the geologist Mathez told me was
probably wurtzite with a little sphalerite thrown in for good
measure, glittered inside the opening, the last metal this
smoker would ever precipitate.
Instead, this unassuming rock from the abyss will precipitate
something finer: scientific understanding and public
education. As we watched ROPOS survey Roane's cleanly sheared
stump on the seafloor tonight, Mathez, with his expedition
co-leader Delaney nodding in agreement, told me that "we have
accomplished one of the major scientific goals of the
expedition, recovering a live sample." A sample that, in
addition to serving as a premier scientific specimen, has
supplanted Phang as the chimney-of-choice for display in the
American Museum.
Unless we find something even better, that is.
Peter Tyson is Online Producer of NOVA.
The Tug of the Thompson (June 23)
The ROPOS Guys (June 25)
In the Juan de Fuca Strait (June 27)
Special Report: A Visit To Atlantis (June 29)
Dive 440 (July 1)
Rescue at Sea (July 2)
What's Your Position? (July 4)
Phang! (July 5)
20,000 Pounds of Tension (July 8)
Four for Four (July 11)
Thrown Overboard (July 13)
Was Grandma a Hyperthermophile? (July 15)
Swing of the Yo-Yo (July 18)
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