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ARLINGTON,
Va.—Scientists working in the stormy and inhospitable
waters off the Antarctic Peninsula have found what they
believe is an active and previously unknown volcano on
the sea bottom.
The
international science team from the United States and
Canada mapped and sampled the ocean floor and collected
video and data that indicate a major volcano exists on
the Antarctic continental shelf, they announced on May
5 in a dispatch from the research vessel Laurence M. Gould,
which is operated by the National Science Foundation (NSF).
NSF
is an independent federal agency that supports fundamental
research and education across all fields of science and
engineering, with an annual budget of nearly $5.58 billion.
NSF manages the U.S. Antarctic Program, which coordinates
U.S. scientific research on the southernmost continent
and in the Southern Ocean.
Evidence
of the volcano came as an unintended bonus from a research
plan to investigate why a massive ice sheet, known as
the Larsen B, collapsed and broke up several years ago.
Scientists hope to understand whether such a collapse
is unique or part of a cycle that extends over hundreds
of thousands of years.
Scientific
evidence the team collected also corroborates mariners'
reports of discolored water in the area, which is consistent
with an active volcano.
Eugene
Domack, a researcher at Hamilton College in Clinton, New
York and the expedition's chief scientist, said the volcano
stands 700 meters (2300 feet) above the seafloor and extends
to within roughly 275 meters (900 feet) of the ocean surface.
He
estimated that the volcanic cone contains at least 1.5
cubic kilometers (.36 cubic miles) of volcanic rock.
By
comparison, Mount Erebus, a known active volcano on Ross
Island near McMurdo Station, NSF's main Antarctic research
center, is approximately 3,800 meters (12,400 feet) above
sea level.
Hawaii's
Mauna Loa, the largest volcano on Earth, rises approximately
4,100 meters (13,600 feet) above sea level. Mexico's Cuexcomate
volcano is considered to be the world's smallest, standing
13 meters (43 feet) tall.
The
research team comprised scientists from Hamilton College,
Colgate University, the Lamont-Doherty Earth Observatory
at Columbia University, Montclair State University in
New Jersey, Southern Illinois University in Carbondale
and Queens University in Canada.
Domack
said the volcano lies in an area known as Antarctic Sound,
at the northernmost tip of Antarctica.
He
noted that there has been "no previous scientific
record of active volcanoes in the region" where the
new peak was discovered and that it is north of an existing
boundary where volcanic activity is known to occur in
the region.
The
volcano, which has yet to be named, also is unusual, Domack
said, in that it exists on the continental shelf, in the
vicinity of a deep trough carved out by glaciers passing
across the seafloor.
Sonar
maps made of the seafloor during a research cruise in
January 2002 first suggested that the volcano exists.
The so-called swath maps showed a large concentric and
symmetrical feature on the ocean floor that had not been
scoured by the advance and retreat of glaciers. The absence
of glacial scours indicates the suspected volcano is fairly
young in geologic terms.
But
it was not until April of this year that scientists were
once again able to venture into the region to examine
the evidence further.
In
addition to mapping, the research team used a bottom-scanning
video recorder, rock dredges, and temperature probes to
survey the sides and crest of the submarine peak. The
video survey revealed a surface that is heavily colonized
by bottom-dwelling organisms.
But
a dark mat of underwater life is broken along the edges
of the volcano by barren patches of dark, black rock indicating
that lava has flowed there. Because no life was found
on these surfaces, the rock is believed to have formed
fairly recently in geologic time.
Rock
dredges recovered abundant, fresh, basalt, which normally
would be rapidly acted upon and transformed by seawater
but appeared unaffected.
Highly
sensitive temperature probes moving continuously across
the bottom of the volcano revealed signs of geothermal
heating of seawater. The heating was noticed especially
near the edges of the feature where the freshest rock
was observed.
These
observations, along with historical reports from mariners
of discolored water in the vicinity of the submerged peak,
indicate that the volcano has been active recently.
Domack
said expects that there will interest among other scientists
to return to the area and study the peak in more detail.
"None
of us on this cruise," he noted, "are experts
in volcanoes."
-NSF-
B-Roll: For Betacam SP video taken by an underwater camera
of the slopes of the volcano and an animation of the camera's
track over the volcano, please contact Dena Headlee, (703)
292-7739, dheadlee@nsf.gov
Still
images from underwater video of the volcano and a drawing
showing the camera's track over the volcano are available
by contacting the media officer listed above.
Media
contacts:
Sharon Rippey, Hamilton College, (315) 859-4691, srippey@hamilton.edu
Charlie Melichar, Colgate University, (315) 317-6871,
cmelichar@mail.colgate.edu
Mary Tobin, Lamont-Doherty Earth Observatory, 845-365-8607,
mtobin@ldeo.columbia.edu
Bob Quarteroni, Montclair State University, (973) 655-4144,
quarteronib@mail.montclair.edu
Tom Woolf, Southern Illinois University, (618) 453-2276,
twoolf@siu.edu
Lorinda Peterson, Queens University, Canada, (613) 533-3234,
petersn@post.queensu.ca
To
see reports posted from research cruise, see:
http://www.hamilton.edu/news/exp/antarctica/2004/
and
http://www.ldeo.columbia.edu/news/reports/2004/CORC04/05_01_04.htm
For
biographies of the researchers on the cruise, see: http://www.hamilton.edu/news/exp/antarctica/2004/faculty.html
For
a list of significant scientific findings from Antarctica,
see: http://www.nsf.gov/od/lpa/news/media/01/fssigsci.htm
For
an NSF news release about the break-up of the Larsen B
ice shelf, see: http://www.nsf.gov/od/lpa/news/02/pr0222.htm
The
National Science Foundation (NSF) is an independent federal
agency that supports fundamental research and education
across all fields of science and engineering, with an
annual budget of nearly $5.58 billion. NSF funds reach
all 50 states through grants to nearly 2,000 universities
and institutions. Each year, NSF receives about 40,000
competitive requests for funding, and makes about 11,000
new funding awards. The NSF also awards over $200 million
in professional and service contracts yearly.
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Courtesy: NSF
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