Mount St. Helens erupts. Courtesy of USGSForty years ago, on May 18, 1980, at 8:32 a.m., an earthquake occurred along the Mount St. Helens seismic zone, shaking the mountain and sending ash, magma and earth flying.
In the months leading up to this eruption, Portland State geologists were tracking Mount St. Helens’ activity, beginning in March when the volcano started rumbling, said Scott Burns, professor emeritus of geology and past president of the International Association of Engineering Geology and the Environment.
“The closest geologists to the mountain were Portland State geologists,” Burns said. “Our faculty were very, very involved in those months of March, April, May and then when the eruption occurred and the recovery afterward.”
After two eruptions in March, the mountain quieted, Burns said. Magma was still moving inside the northern part of the mountain, creating a bulge that crept five feet a day. The United States Geological Survey (USGS) sent people to the area, instrumenting the mountain with seismographs and tools to measure the bulge and analyze gas vents called fumarole.
When the mountain erupted again two months later, the bulge of magma thrust down the hill, creating the largest landslide in recorded history and sending debris into Spirit Lake and 25 kilometers down the North Fork Toutle River.
“All the gases and magma in there shot out as ash,” he said. “Some went out laterally, and then upward, and then the whole thing just went wild.”
The USGS geologists couldn’t be everywhere at once, so PSU geologists Len (Leonard) Palmer, Marvin Beeson and Tom Benson stepped in to interview with news outlets, collect data and perform research. “Every night there would be at least one PSU geology professor on TV,” Burns said.
Ken Cameron ’76 MS ’80, Rita Gabor, and an unidentified student, look at a map of Oregon and Washington, where the PSU geography department was tracking volcanic activity at Mount St. Helens.Many news outlets came to take photos and collect data from the Geology Department’s seismograph. PSU was also tracking the volcano’s activity on a map. (See the photo of Ken Cameron ’76 MS ’80, Rita Gabor, and an unidentified student.) In the months following the May 18 eruption, there were several big eruptions, one of which covered Portland with inches of ash.
Later, the Cascades Volcano Observatory was created in Vancouver, decreasing the demand for PSU’s geological expertise. However, PSU is still connected to the eruption, Burns said. Several students in the Geology Department have done related thesis work, some professors are still involved in Mount St. Helens research, and three times a year, Burns and other professors lead field trips to the mountain. Also, a recording of Benson explaining the May 18 eruption from a helicopter can still be heard at the Mount St. Helens Forest Learning Center to this day.