From Associated Press
PORTLAND,
Ore.--A significant bulge in the Earth's crust has developed over
the last four years near volcanoes in central Oregon, but it's
not clear whether that presages a volcanic eruption, geologists
said Tuesday.
The bulge--9
to 12 miles across and about 4 inches high--was detected by satellite
radar, said Willie Scott, a scientist at the U.S. Geological Survey's
volcano lab in Vancouver, Wash.
"Because
it's a volcanic area and there's been a long history of volcanic
activity in that part of the Cascades, it's possible it might
be magma, or molten rock, moving deep underground," Scott
said.
The bulge
is near the Three Sisters, three volcanoes at the center of the
Cascade Range in Oregon.
The last major
eruption in the Pacific Northwest occurred in May 1980, when Mt.
St. Helens blew off about 1,300 feet of its top.
The uplift
is too broad and low to be noticed from the ground.
Scientists
have looked across the West for signs of bulges, but this is the
first prominent change on record using this technique.
"But
there's nothing right now that makes us think there's an imminent
danger" of an eruption, Scott said.
The Cascades,
which run from California into British Columbia, have several
volcanic peaks.
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