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Scientists confirm submarine volcanic eruption 300 miles off the coast of Washington State – massive ‘quiet’ lava burst
![Axial Submarine Volcano 1](https://theextinctionprotocol.files.wordpress.com/2015/04/axial-submarine-volcano-1.png?w=640)
April 2015 – SEATTLE – More
than 80 scientists from around the world gathered in Seattle last week
to discuss a thrilling development: For the first time, seafloor
instruments were providing a real-time look at the most active,
submarine volcano off the Northwest coast — and all signs indicated it
might erupt soon. But even the researchers most closely monitoring Axial
Seamount were stunned by what happened next. Beginning Thursday, April
23 — the day after the workshop ended — the new sensors recorded 8,000
small earthquakes in a 24-hour period. The volcano’s caldera, which had
been swelling rapidly from an influx of magma, collapsed like a deflated
balloon. “All the alarm bells were going off,” said Oregon State
University volcanologist Bill Chadwick, who along with a colleague
predicted last year that the volcano would erupt in 2015. “It was very
exciting.”
Scientists are still debating whether
to describe what transpired as an eruption, which means molten rock
flowed onto the seafloor. No instruments were destroyed and there was no
obvious temperature spike, so the magma might have oozed into
subterranean fissures, forming what’s called a dike. Chadwick is among
those who suspect lava did burst out, probably north of where the new
instruments are clustered. “This was a major event,” he said. “A lot of
magma moved, and that makes a lot of us think it had to erupt
somewhere.” The only way to find out for sure is to visit the site with a
research vessel, which he and his colleagues will do this summer. But
despite the ambiguity, the ability to monitor the submarine upheaval as
it unfolded marks a major milestone for the United States’ first
underwater observatory. Operated by the University of Washington and
completed last fall, the $200 million network includes 600 miles of
coaxial cable on the seafloor that powers and delivers data from scores
of seismometers, tilt meters, microbial samplers and other instruments.
UW oceanographer John
Delaney first proposed the system nearly two decades ago, and is
delighted to finally see the vision realized — and bearing scientific
fruit. “It’s like Christmas squared,” he said. “This proves beyond a
doubt the value of the cable and the data that’s flowing ashore.”
Delaney helped organize last week’s workshop for scientists interested
in tapping the new source of data on Axial Seamount, and in discussing
the current volcanic unrest. The seafloor network is part of the
National Science Foundation’s Ocean Observatories Initiative. It’s
designed to study everything from marine life to water chemistry and
plate tectonics. Nearly 30 instruments are situated on or around Axial
Seamount, because so much is going on there. “This is really the only
observatory in the world on an active, underwater volcano,” said UW
oceanographer Deborah Kelley.
Topping out at about 3,000 feet high,
Axial is more like Hawaii’s shield volcanoes than the Cascades’ towering
cones. It straddles the Juan De Fuca Ridge — a seam in the ocean bottom
where magma wells up and fresh seafloor is born. Most of the
instruments are concentrated in the volcano’s central caldera, which is
nearly 2 miles wide and 5 miles long. The caldera is also dotted with
hydrothermal vents and fantastical chimneys called black smokers, which
Kelley has studied for years, along with the communities of tube worms
and heat-loving microbes that thrive in the inhospitable conditions. But
Axial isn’t easy to get to. It lies under nearly a mile of water and
sits almost 300 miles offshore. –Seattle Times
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