"Bart Senior" .@. wrote in message ...
http://www.sciencedaily.com/releases...1125050151.htm

"Volcano Of Fire" Could Be Entering Its Most Dangerous Phase In Nearly A
Century, UB Expert Says

BUFFALO, N.Y. -- The eruption of Colima volcano -- also known as Volcan
del Fuego, or "Volcano of Fire" -- that began on Nov. 20 has produced its
first pyroclastic flows that could signal the start of the volcano's most
dangerous period since its catastrophic eruption in 1913, a University at
Buffalo volcanologist says.

Michael F. Sheridan, Ph.D., professor and chair of the UB Department of
Geology and a co-author of the current hazards map of Colima, says that
while activity at the volcano may continue in "fits and starts," the weak
condition of the volcano summit, combined with the weight of lava that is
now emerging, has created an extremely unstable situation.
Two nearby villages, Yerba Buena and Juan Baragan, were evacuated last
week.

In Spring 1991, computer simulations developed by Sheridan accurately
predicted the course and magnitude of pyroclastic avalanches from Colima
that occurred shortly afterward.

Last month, at the annual meeting of the Geological Society of America,
Sheridan reported that extremely fast-moving volcanic mudflows could
inundate and destroy a large part of a key industrial town located
northeast of Colima sometime within the next 10 years.

That would be the case, he says, only if a major explosion should occur as
a result of pent-up pressure at the volcano's summit, and if a blanket of
volcanic ash from the volcano was mobilized by torrential rains, which
could come next spring or earlier.

"While there is still considerable uncertainty whether the current
activity is a prelude to a major event, all of the precursors, such as the
lava emission at the summit and the formation of pyroclastic flows, have
already occurred," Sheridan says.
There is fresh magma at the summit and the slope is very steep, he adds.

"As magma surges upward, the volcano swells and unstable slopes begin to
crumble and slide, becoming avalanches," he says. "This mixture of older,
cool lava and new, red-hot magma can become fluidized and cascade down the
volcano's sides at speeds of 100 miles per hour or more."

According to Sheridan, this could produce incandescent dust clouds so
thick that people caught in them can die from severe burns or suffocation.

He adds that Colima currently is emitting 4,000 tons of sulfur per day,
enough to produce a significant cooling effect on the global climate if
the eruption continues.

A pioneer in developing computerized simulations of volcanoes that allow
researchers to estimate how fast and how far ash flows from an eruption
will travel, Sheridan has been honored by the University of Colima for his
scientific work on the activity of the volcano and for his training of
young Mexican scientists at UB and elsewhere.

The most dangerous volcano in Mexico, Colima has erupted violently three
times during the past 450 years. About 2,300 years ago, it produced a
cataclysmic avalanche much larger than that of Mount St. Helens in 1980.

I actually went on a trip to climb Colima, but ran into trouble with
authorities. It's a small volcano.

Check out what Mt Erebrus dumps into the atmosphere.

Lloyd