wow! I dnt knw if to be thrilled or scared.
Scientists using 3-D scanning of
the deep interior of Earth have
found evidence of a vast water
reservoir beneath eastern Asia
that is at least the volume of the
Arctic Ocean -the first time such a
large body of water has found in
the planet’s deep mantle.
The finding, made by Michael
Wysession, a seismologist at
Washington University in St.
Louis, and his former graduate
student Jesse Lawrence, now at
the University of California, San
Diego, was made by
analyzing more than 600,000
seismograms—records of waves
generated by earthquakes
traveling through the Earth—
collected from instruments
located around the planet.
The team discovered a region
beneath Asia where seismic
waves appeared to dampen, or
“attenuate,” and also slow down
slightly. “Water slows the speed
of waves,” Wysession explained.
“Lots of damping and a little
slowing match the predictions
for water very well.”
Their research proved out earlier
predictions that calculated that if
a cold slab of the ocean floor
were to sink thousands of miles
into the Earth’s mantle, the hot
temperatures would cause water
stored inside the rock to
evaporate out.
The researchers estimate that up
to 0.1 percent of the rock sinking
down into the Earth’s mantle in
that part of the world is water,
which works out to about an
Arctic Ocean’s worth of water.
Wysession has dubbed the new
underground feature the
“Beijing anomaly,” because
seismic wave attenuation was
found to be highest beneath the
Chinese capital city (see image
left above showing increased
attenuation in Asia) . Wysession
first used the moniker during a
presentation of his work at the
University of Beijing.
“They thought it was very, very
interesting,” Wysession said.
“China is under greater seismic
risk than just about any country
in the world, so they are very
interested in seismology.”
Water covers 70 percent of
Earth’s surface and one of its
many functions is to act like a
lubricant for the movement of
continental plates.
just reading about dis for the first time..thanks man!
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