SAN FRANCISCO (AP) — Scientists have recorded the deepest
erupting undersea volcano ever seen, capturing for the first time video of
fiery molten lava bubbles exploding 4,000 feet beneath the Pacific
Ocean.
A submersible robot witnessed the eruption in May during an
underwater expedition near Samoa, and the high-definition videos were presented
Thursday at a geophysics conference in San
Francisco.
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In this image taken from a May 7, 2009 video and provided by the National Science Foundation and the National Oceanic and Atmospheric Administration, a plume of sulphur and molten lava erupts from the West Mata Volcano nearly 4,000 feet beneath the Pacific Ocean, south of Samoa. Scientists have captured on video fiery bubbles of molten lava, calling it a major geological discovery. Federal ocean scientists are presenting the video in San Francisco at a geophysics conference on Thursday, Dec. 17, 2009. (AP Photo/NSF NOAA)
Scientists hope the images, data and samples obtained during
the mission will shed new light on how the earth's crust was formed. The
research could also help explain how some sea creatures survive and thrive in
extreme environments and how the earth behaves when tectonic plates collide.
"It was an underwater Fourth of July," said Bob
Embley, a marine geologist for the National Oceanic and Atmospheric
Administration, in a news release. "Since the water pressure at that depth
suppresses the violence of the volcano's explosions, we could get the
underwater robot within feet of the active eruption."
The eruption was a spectacular sight: Bright-red lava
bubbles shot out of the volcano, releasing a smoke-like cloud of sulfur. The
lava froze almost instantly as it hit the cold sea water, causing black rock to
sink to the sea floor. The submersible hovered near the blasts, its robotic arm
reaching into the lava to collect samples.
Earth and ocean scientists said the eruption allowed them to
see for the first time the creation of a material called boninite, which had
previously been found only in samples at least a million years old.
In the past, boninite lavas had only been found on extinct
volcanoes, so researchers were excited to see firsthand how they are created,
Resing said.
Hubert Staudigel, a volcanologist at the Scripps Institution
of Oceanography in San Diego,
said other undersea eruptions have been recorded before, but that this record
presents exciting new opportunities for study. Staudigel was not involved in
the West Mata trip.
"We have seen all kinds and types of eruptions before
this. But this type of eruption we've never seen before," he said.
"This type of eruption is what makes up most of the sea floor volcanoes,
so to see it live is an amazing thing to see."
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In this image taken from a May 7, 2009 video and provided by the National Science Foundation and the National Oceanic and Atmospheric Administration, shrimp surround a volcanic vent on the West Mata Volcano nearly 4,000 feet beneath the Pacific Ocean, south of Samoa. Scientists have captured on video fiery bubbles of molten lava, calling it a major geological discovery. Federal ocean scientists are presenting the video in San Francisco at a geophysics conference on Thursday, Dec. 17, 2009. (AP Photo/NSF NOAA)
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"To be next to it with a (robot) allows you to make
some really close observations. You get an idea of how fast these things
flow."
The mission to record a deep-sea volcanic eruption was 25
years in the making. Although 80 percent of the earth's volcanic activity
occurs in the sea, scientists from NOAA and the National Science Foundation had
never witnessed an eruption this deep and in this detail.
The mission's chief scientist, Joseph Resing, last year
detected volcanic material in the water near the West Mata volcano, about 140
miles southwest of Samoa. In May, researchers arrived with a submersible robot
called Jason.
"When we got there, we put the sub down, and within in
an hour and a half we found an eruption there in its full glory," said
Resing, who is a chemical oceanographer at the University of Washington.
"We haven't seen this before. And now for the very first time, we see
molten lava flowing on the sea floor."
Scientists said some water samples around the volcano had an
acidity registering between battery acid and stomach acid, but shrimp and
certain microbes were able to thrive. Biologists were also excited about a new
opportunity to study the creatures to see if they are unique to this volcanic
environment.
Tim Shank, a biologist at the Woods Hole Oceanographic
Institution in Massachusetts,
said the deep-sea eruption will help researchers study how life survives in an
extreme underwater environment.
"Deep sea biologists are obsessed with determining the
rate of processes, how fast something happens. The anticipation here is if this
ground remains unstable because of lava pushing out and breaking away, it will
not provide a surface area for these organisms to colonize," he said.
