TALLAHASSEE, Fla. — The devastating eruption of the Fuego volcano in Guatemala and the ongoing lava flows streaming from Hawaii’s Mount Kilauea serve as unwelcome reminders of the destructive potential of active volcanoes.
Vincent J.M. Salters, a volcano expert and professor in Florida State University’s Department of Earth, Ocean and Atmospheric Science, is available to discuss the recent examples of volcanic activity and the precautions vulnerable populations can take in the event of an eruption.
What made the volcanic eruption in Guatemala so deadly?
“The eruption of the Fuego volcano was a very large explosion that resulted in a pyroclast flow — a fast moving river of hot lava blocks, pumice, ash and volcanic gas. The explosion was caused by volatile gasses that were originally dissolved in the magma. When magma cools too far or crystalizes too much or decompresses on the way to the surface, the volatiles escape violently out of the magma causing an explosion. You can compare it to opening a carbonated beverage after you shake the bottle.
“This explosion sends magma and gas spewing out of the volcano and propels it high up into the air. The hot material comes rushing down the mountain at speeds that can reach 400 mph. This volcano had several eruptions (small ones) last year and seismic activity was already enhanced. The seismic activity did not perceptibly increase before this last big eruption, and therefore not enough people were evacuated in time.”
Does the continued volcanic activity in Hawaii pose an immediate threat to the people living there?
“The Kilauea eruption is not a threat to people living in Hawaii, but it is a threat to their belongings if they are in the path of the lava. The volatile (mainly water) content of the Hawaiian lava is much lower and it flows easily, so there is no possibility for stress to build up and cause a violent eruption.
“There can be a danger point where the lava flow enters the ocean. The very quick evaporation of the ocean water releases compounds like chlorine and sulfate into the air, which can be bad for your health if inhaled. Sudden wind shifts can quickly send such a cloud toward people who are too close to the entry point into the ocean.”
What can people in areas with high volcanic activity do to protect themselves in the event of an eruption?
“Luckily we do not have many volcanoes with high volcanic activity at the moment in the continental U.S. Mount St. Helens is our most active volcano, but it is very well monitored by officials.
“The best protection is heeding official evacuation warnings. In Japan, where some population centers are near volcanoes that have frequent eruptions, children will often wear helmets to school during times of high activity. In the event of an eruption at a place where you are hiking, the best thing to do is to avoid the valley and have a ridge between you and the volcano.
“Some of the deadliest eruptions are associated with mudflows. If there is snow on the volcano, the eruption can melt the ice and send a mixture of water, ash and pyroclastics racing down the mountain toward the lowest contour, i.e. through the valleys where most people live. Mudflows are like huge flows of cement. They take everything down with them and once something or someone is trapped, it is near impossible to get out.”
To arrange an interview, contact:
Vincent J.M. Salters, professor of geology, Department of Earth, Ocean and Atmospheric Science: (850) 644-1934; [email protected]