BUFFALO, N.Y. -- Flying over a volcano that's sending plumes of
smoke and ash several miles into the sky might sound like a risky
proposition, but University at Buffalo volcanologist Michael
Sheridan and his colleagues are doing just that this week with
Ecuador's towering 5,000-meter-high Tungurahua volcano as they
study how and where it next will do its damage.
The steep-sided Tungurahua, which means "Throat of Fire" in the
Quechua Indian language, has been active since 1999, when
approximately 25,000 inhabitants of surrounding cities and
villages, including the popular tourist destination Banos, were
evacuated because of fears of a massive eruption.
Residents returned a few months later and are reluctant to move
again, Sheridan said, although the volcano remains active,
periodically sending smoke and emissions up several miles into the
atmosphere.
Sheridan's objective is to combine high-tech images he will
obtain from the flight with a new 3D-visualization system he and
other UB scientists have developed to create the most accurate,
detailed picture they can of a volcano's destructive
capabilities.
His fly-over with volcanologists Menard Hall and Patty Mothes of
the Geophysical Institute of the National Polytechnic School in
Quito, Ecuador, will be filmed by a production crew for the
Discovery Channel for a documentary on new techniques in
forecasting and mitigating volcanic hazards.
The goal of the volcanologists is to provide civil protection
authorities with the most detailed information about how lava flows
and mudflows from the volcano will affect residents, and what would
be the safest route out of the region should evacuation become
necessary.
"This is the first time that hyperspectral information is being
used in direct connection with a volcanic crisis for hazard
mitigation," said Sheridan.
The plane is equipped to do hyperspectral imaging -- described
by Sheridan as a "geologic X-ray" -- where sensitive hyperspectral
sensors projecting from the bottom of the plane gather detailed
data about solar-energy absorption and radiation on different areas
on a volcano's surface. From that information, the scientists can
identify the mineral composition of analyzed areas, revealing, for
example, if a certain spot is altered or composed of fresh rock,
information that may signal that an imminent collapse of the crater
is possible.
The visualization system developed by Sheridan and Christopher
Renschler, Ph.D., UB assistant professor of geography, allows for
the simultaneous visualization and integration of many types of
data, a flexible tool that allows scientists to put overlays of any
kind of geographic information on top of 3-dimensional
topographical models that then can be rotated and analyzed.
"It's like putting on different kinds of glasses," said
Sheridan, "where each pair gives you a different view, in one case
actually allowing you to see the ground as it exists beneath the
vegetation.
"By putting these layers on top of one another, we can then
extrapolate where pyroclastic flows and avalanches are likely to
start, and how far and how fast they will travel," he said.
Mohammed Sultan, Ph.D., UB professor of geology, provided
geologic data obtained from remote sensing by satellites for this
geographic information system (GIS).
Because the GIS component of the data includes features such as
the precise location of rivers, roads, bridges and houses, this
graphical user interface, which the UB scientists call Geo-DRAT
(Geo-Spatial Dynamic Response Assessment Tool), will help
scientists predict whether an avalanche or mudflow may plug up a
nearby river and produce overbank flows that could flood a
town.
"That kind of information is critical, because in 1773, 1886 and
1916 volcanic flows from the Tungurahua flowed into the Rio
Pastaza, just to the north of the volcano," said Sheridan. "That
river now is the site of one of Ecuador's biggest hydroelectric
dams, so if the same thing happens now, the disaster would impact a
much larger area, potentially cutting off power to a large region
of the country."
Sheridan added that Geo-DRAT's ability to superimpose different
layers of data, including satellite images, on top of 3-dimensional
topography, easily could be applied to different natural or manmade
disasters. It could determine, for example, where illnesses have
clustered after a chemical or biological agent attack.
"It's a general platform for presentation and analysis of
disaster-related data," said Sheridan.