Mount St. Helens is an iconic peak in the Pacific Northwest, offering magnificent views of fields of flowers and lush forests. A time-honored destination for locals and tourists, the mountain’s reputation as a playground belied its true character as a dangerous volcano.
In the decades prior to 1980, U.S. Geological Survey scientists Dwight Crandell and Donal Mullineaux researched the potential hazard posed by the volcano. Their extensive geologic mapping and dating of the volcano’s previous deposits uncovered something unexpected: though Mount St. Helens was known to be one of the youngest volcanoes of the Cascade Range, scientists had not appreciated just how young and recently active the mountain was, and the implications this had for future eruptions. Crandell and Mullineaux published their findings in the mid-1970s, stressing that another eruption would occur, and soon.
Between March and May 1980, Mount St. Helens started acting up. The area was closed off as a precaution, but the public was concerned about tourism and the economy, and urged the State to reopen the lands. As these heated discussions were taking place, volcanic activity escalated. Swarms of earthquakes, steam explosions, and a growing bulge emerged and expanded from the throat of the volcano. Then, on May 18th, there was a landslide, lateral blast, multiple lahars, pyroclastic flows, and an explosion of ash. Scientists watched with bated breath, learning and documenting as much as they could.
This eruption shook everyone, and particularly jumpstarted the field of volcanology. Prior to this eruption, volcano science in the U.S. focused on Hawaiian volcanoes of the mostly effusive nature, located on volcanic islands in the middle of the Pacific. Mount St. Helens revealed an entirely different beast, and one that was living under our noses.
This eruption was a wake-up call and a learning opportunity for science, for hazard forecasting, and for disaster response. Following the eruption, the U.S. Geological Survey established the Cascades Volcano Observatory to monitor St. Helens and other volcanoes.
Continued monitoring of Mount St. Helens records enduring earthquake activity. The summit that was blown off in 1980 is rebuilding, reminding us that Mount St. Helens is very much an active volcano. The uncorking of St. Helens in 1980 and its ongoing activity will continue to shape our understanding of volcanic processes and landscape evolution in Washington and around the world.
WASHINGTON STATE GEOLOGY NEWS 