UB Researcher Develops Volcano Risk Map



Thanks to a team of researchers from UB and the National University of Mexico, authorities in regions at-risk of volcano eruptions now have a way of detecting the direction of lava flow - and possibly mitigating harm from previously unpredictable eruptions.

The risk map developed by Michael Sheridan, UB professor and volcanologist, will enable scientists to predict which populated areas will be affected in the event of an eruption, as well as providing alternative routes and locations for evacuation.

The Popocatepetl volcano is located in a populous vicinity of Mexico containing approximately 30 million people, only 60 kilometers from Mexico City, and has been active since December 1994.

"There is a better than 50 percent confidence that if the next big eruption is similar in size to the eruption of 800 AD - the last big event - this map will portray the areas likely to be affected," said Sheridan.

If successful, the risk map will help alleviate the pressure on Mexican authorities by making emergency evacuation safer and more effective.

"Civil Protection Authorities use hazard/risk maps to formulate plans for emergency response and evacuation. Therefore a good hazard/risk map will be simple enough to be understood by the local population, while providing critical information about which areas are safe and which areas are not relative to population centers and evacuation routes," stated Bernard Hubbard, a post-doctoral research scientist at the U.S. Geological Survey in Washington, D.C.

"There are more active volcanoes in the U.S. than in any other countries," said Sheridan, pointing out the practical application of the risk mapping closer to home.

Most of the volcanoes are concentrated in the western half of the United States, although some are located in Alaska's Aleutian Islands and Hawaii. Seattle, Wash., however, is an example of a dense urban area in close proximity to volcanic activity.

Risk maps are restructured to take into consideration changes in the environment, population growth, and urban or rural developments. The risk map generated for Popocatepetl was created using computer models and assisted by a Geographic Information System (GIS), which provides topographical and geographical data.

According to Hubbard, "The modeling was based on information gathered using remote sensing data and several seasons of fieldwork in Mexico. We specifically looked for a record of the size and frequency of hazardous events in the past by studying rocks collected near the summit of the volcano and from deposits around its flanks."

The central design of the significant-risk maps is composed of two models that track different flows, or materials observed during a volcano's 'active' or eruptive period. The first model tracks the pyroclastic flows, which consist of powerful, swiftly moving and extremely hot gases and particles.

The second model portrays the movement of mud flows, a byproduct of eruptions made of a combination of volcanic ash and water.

The authors of the Popocatepetl Risk Maps are Sheridan; Jose Luis Macias Vazques, chairman of the volcanology department at the National University of Mexico and PhD graduate from UB; Gerardo Carrasco Nunez, Hugo Delgado Granados, Ana Lillian Martin Del Pozzo and Claus Siebe Grabach, all professors at the department of geophysics at the National University of Mexico; Richard P. Hablitt, with the U.S. Geological Survey; and Robert I. Tilling, also with the U.S. Geological Survey and an advisor regarding volcanic hazards throughout the world.