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Birth of an Expedition
Part 2 (back to Part 1)
An expedition is born
Then John Delaney,
the co-leader of this expedition, had a brainstorm. Why
not retrieve a black smoker or two off the seabed? Sure, the flow of
superheated chemicals would stop and the attendant life forms would quickly
perish when brought to the surface. But geologists could study how the chimneys
grow, how fluids flow through them, and what role microbial life plays in their
evolution. And biologists could be standing by as the smoker came up to examine
the life forms, everything from the chemical-eating microbes to the giant
tubeworms.
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Black smoker photographed from submersible.
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Delaney, a geologist at the University of Washington, convinced his colleague
and friend, geologist Edmond A. Mathez of the American Museum of
Natural History, of the significance of this attempt, and an expedition was
born. Their two institutions are collaborating in the effort.
The University of Washington is focusing on research and science education,
while the American Museum is hoping to increase public understanding of
this unusual world by acquiring a black smoker for its new Hall of the Planet
Earth, slated to open in summer 1999.
Delaney knew exactly where he'd go for a black smoker. In 1982, one of the
most impressive sites for black smokers was discovered practically in his
backyard: on the Endeavour Segment of the Juan de Fuca Ridge. The Juan de Fuca,
part of the 46,000-mile mid-ocean ridge that zippers the globe, is a spreading
center, where new seafloor is created. And the Endeavor Segment hosts one of
the most vigorous hydrothermal systems yet identified. It features at least
four major, high-temperature vent fields, each about 1,000 feet on a side, with
whole forests of black smokers crawling with red-tipped tubeworms, gangly white
crabs, and the like.
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Godzilla, the largest black smoker yet identified.
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The expedition began in September 1997 with a "site characterization" cruise
to the Endeavour Segment. Delaney and colleagues used the remotely operated vehicle Jason,
equipped with acoustic and optical imaging systems, to minutely photograph and
map several target black smokers. They showed that these geysers can grow up to
an inch or so a day and can collapse of their own weight; Godzilla, a smoker
some 14 stories tall, did so a few years back. The targeted smokers are more
modest, the biggest one about 10 feet tall and weighing some 15,000
pounds.
Going after a smoker
On June 25, 1998, the oceanographic research vessel Thomas G. Thompson will
head out to the Endeavor Segment from Seattle in an attempt to realize
Mathez and Delaney's dream. This time, no manned submersible will be used. Instead, the
researchers will use the aforementioned remotely operated vehicle. It's called
ROPOS, for Remotely Operated Platform for Ocean Science. This robot is
tethered to the ship with cable, through which images from its on-board cameras
and other data can be sent along in real-time.
Piloted by Shepherd, ROPOS will first examine and photograph the black smoker,
for before-and-after studies. It will then cinch wire loops tightly around it.
These cables are attached to an 8,000-foot-long line coming off a 30,000-pound
winch on the deck of the Canadian Coast Guard research vessel John P. Tully,
which will perform the actual recovery. ROPOS will then use a hydraulic,
diamond-embedded chain saw to cut notches in the base of the smoking chimney,
just as foresters do when cutting down trees. Only when the robot is well out
of the way will engineers aboard the Tully take the slack out of the cable to
the surface and apply full force to the winch.
Nobody knows what will happen then. The hope is that the black smoker will
break free cleanly and be brought in one piece to the surface. But this has
never been tried before. Will the smoker stump explode? Will the smoker itself
break apart? What will happen in the immediate vicinity of the smoker? Will
engineer Le Olson succeed in lifting it to the surface? What effect
will the change in pressure and temperature have on it?
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Canadian Coast Guard ship John P. Tully.
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If the team succeeds and manages to hoist a steaming, seven-and-half-ton
smoker onto the Tully, geologist Deborah Kelley and her team take over.
They will use a diamond-embedded wire saw to slice the smoker in half. One half
will be set aside for the American Museum; the other half will immediately
undergo intensive study by a crew of microbiologists, fluid chemists,
mineralogists, and marine scientists. The
Thompson will remain behind to gauge the aftermath of the retrieval.
Will the stump regrow? Will wildlife recolonize it, and if so, how
quickly?
The R/V Thomas G. Thompson.
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Bookmark this site to follow the course of this ground-breaking expedition to
the bottom of the sea—a mission that might hold clues to the very beginnings
of life on Earth, if not elsewhere in the solar system.
Peter Tyson is Online Producer of NOVA.
Birth of an Expedition |
Mission Plan |
Dispatches
Through the Porthole |
Meet the Team
Meet ROPOS (JavaScript/Frames-capable browser required)
Meet ROPOS (No Frames/JavaScript)
Photos: (1-2) NOAA/Pacific Marine Environmental Laboratory; (3) © Woods Hole Oceanographic
Institution/Dr. Robert Hessler; (4) Dimitry Schidlovsky;
(5) V. Tunnicliffe; (6) Visuals Unlimited/© WHOI/D. Foster;
(7) D. Kelley; (8) V. Robigou; (9) Fisheries and Oceans/Canada; (10) University of Washington; (11) Marine Operations, UW School of Oceanography.
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