Off the coast of Oregon, about 300 miles away, an underwater volcano seems to be awakening. Scientists who have been studying this expansive submarine volcano for many years have noted a recent surge in activity, such as an increase in earthquakes in the area and expansion of the structure itself, indicating that an eruption may be imminent. According to Bill Chadwick, a volcanologist and research professor at Oregon State University, current projections suggest that the volcano, known as Axial Seamount, could erupt at any time between now and the end of the year.
Chadwick and fellow researchers from the University of Washington and the University of North Carolina Wilmington have been utilizing a network of sensors on the ocean floor to monitor the volcano. In recent months, these instruments have detected signs of activity at Axial Seamount. For example, in late March and early April, researchers recorded over 1,000 earthquakes per day. Additionally, the volcano has been gradually swelling, indicating a build-up of molten rock within.
Unlike some volcanoes in Hawaii, an eruption at Axial Seamount poses no real threat to humans. The volcano sits hundreds of miles offshore and is submerged about a mile beneath the surface of the water. This remote location means that even a significant eruption would go unnoticed on land.
Although the eruption would not impact people directly, it would undoubtedly be a remarkable event. During the volcano’s last eruption in 2015, a substantial amount of magma flowed out, with one lava flow reaching a thickness of about 450 feet, nearly two-thirds the height of Seattle’s Space Needle.
Axial Seamount was formed by a hot spot, where molten rock rises from Earth’s mantle to the crust. This geological process is not uncommon, but what sets Axial Seamount apart is its location at the boundary between the Pacific plate and the Juan de Fuca plate, two massive tectonic plates that are moving apart. The separation of these plates and the resulting pressure beneath the ocean floor continuously fuel volcanic activity, creating fresh ocean crust in the area.
Chadwick has been studying Axial Seamount for the past three decades, during which the volcano has erupted three times: in 1998, 2011, and 2015. As researchers prepare for a potential eruption, they are exploring whether recurring patterns of activity at Axial Seamount can lead to reliable predictions about when the volcano might erupt. However, forecasting eruptions remains a challenging endeavor due to the unpredictable nature of volcanoes, with different types exhibiting varying behaviors.
“It is more challenging to forecast volcanic eruptions than it is to predict the weather, which is already a complex task,” explained Scott Nooner, a geophysics professor at the University of North Carolina Wilmington. “There is still much we do not comprehend about the triggers of eruptions and the movement of magma beneath the Earth’s surface.”
While short-term forecasts, typically hours before an eruption, have been somewhat successful in assisting local officials with evacuation decisions, long-term forecasts remain difficult to achieve. This is why Axial Seamount is considered an excellent natural laboratory for improving eruption forecasting tools, according to Nooner.
“On land, an inaccurate forecast of a volcano erupting within a week or a month can have significant financial, temporal, and emotional costs,” Nooner noted. “Yet, at Axial Seamount, we do not face these consequences as the eruptions do not affect anyone. This allows us to test and refine our models and forecasts without the same level of impact seen with land-based volcanoes.”
