Release Date: October 9, 2002
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.