The most active volcano in the Pacific Northwest could erupt ‘any day now,’ scientists have warn.
The Axial Seamount is a mile-wide underwater volcano that sits 300 miles off the coast of Oregon and more than 4,900 feet below the surface of the Pacific Ocean.
It last erupted in 2015, triggering roughly 8,000 earthquakes, producing 400-foot-thick lava flows and causing the bottom of the ocean to sink nearly eight feet.
Scientists monitoring this volcano have detected a key sign that it is about to erupt: inflation of the seafloor.
This swelling indicates that magma is building up beneath the surface.
According to William Wilcock, a professor and marine geophysicist at the University of Washington, the seafloor has already inflated to the level that it reached before the 2015 eruption.
‘Some researchers have hypothesized that the amount of inflation can predict when the volcano will erupt,’ he said.
‘That means it could really erupt any day now, if the hypothesis is correct.’
The Axial Seamount is a mile-wide underwater volcano that sits 300 miles off the coast of Oregon and more than 4,900 feet below the surface of the Pacific Ocean. One of Axial Seamounts many hydrothermal vents, which are part of a complex, sprawling network
Scientists monitoring this volcano have detected a key sign that it is about to erupt: inflation of the seafloor. Pictured is the opening of the volcano
If Axial Seamount does blow, however, it won’t post any threat human communities, experts say. It’s too deep and too far from shore for people to even notice when it erupts, and it has no impact on seismic activity on land.
Mike Poland, a scientist at the Yellowstone Volcano Observatory, expressed excitement about the eruption, highlighting Axial Seamount as one of the world’s best-monitored submarine volcanoes.
‘This particular volcano is probably the best-monitored submarine volcano in the world,’ he told Cowboy State Daily. ‘It’s fascinating and doesn’t really pose a hazard.’
Situated along the Juan de Fuca Ridge, a chain of undersea volcanoes extending between Oregon and Alaska, Axial Seamount is a young shield volcano – a broader volcano with a low profile.
‘When Axial Seamount erupts, it’ll look a lot like a Hawaiian lava flow eruption,’ Poland said.
‘It’s not an explosive eruption, but calm effusions of lava flowing out of the caldera and across the seafloor.’
Scientists warned last year that Axial Seamount was going to erupt by the end of 2025.
‘Because it’s had these three eruptions in the last 30 years, that’s why we call it the most active volcano in the Pacific Northwest, because most of the ones on land aren’t active that frequently, and they spend a lot of their time slumbering, whereas Axial has a pretty active magma supply,’ Chadwick told local CBS affiliate KOIN 6 News.
If Axial Seamount does blow, it won’t post any threat human communities, experts say. It’s too deep and too far from shore for people to even notice when it erupts, and it has no impact on seismic activity on land
‘So, if it’s not erupting, it’s inflating and getting ready for the next one. And so that’s why we’re kind of monitoring what’s happening to it all the time.’
Eruptions from Axial Seamount were recorded in 1998, 2011 and 2015, and the volcano has undoubtedly erupted numerous times prior to those events, according to Poland.
In November 2024, Oregon State University geophysicist William Chadwick started investigating the volcano when he noticed its surface had swelled to nearly the same height it reached before its last eruption 10 years ago.
The swelling that occurred prior to the 2015 eruption allowed Chadwick and his colleagues to predict that event.
This massive underwater volcano sits 300 miles off the coast of Oregon and more than 4,900 feet below the surface of the Pacific Ocean
This time, their observations told them that Axial Seamount would erupt before the end of 2025.
‘Based on the current trends, and the assumption that Axial will be primed to erupt when it reaches the 2015 inflation threshold, our current eruption forecast window is between now (July 2024) and the end of 2025,’ the researchers reported.
They also found that seismic activity at Axial Seamount had increased, with hundreds of earthquakes generated around the volcano per day and earthquake swarms greater than 500 per day.
Frequent, small earthquakes like these can signal that magma locked beneath the ocean floor is creeping closer to the surface.
They shared their findings at the annual American Geophysical Union conference in December 2024.
The first sign that an eruption from this volcano is imminent will be a sharp increase in the number of earthquakes around it, according to Wilcock.
Scientists monitoring the Axial Seamount have detected a key sign that it is about to erupt: inflation of the seafloor
‘That period lasts about an hour, and then the magma reaches the surface,’ he said in a statement.
After that, ‘the seismic activity dies down pretty quickly over the next few days, but the eruption will continue slowly for about a month,’ he said.
This upcoming event will be a major research opportunity for Wilcock and other scientists, who plan to use a suite of high-tech instruments to monitor the eruption from start to finish.
The University of Washington’s College of the Environment hosts one of the largest underwater observatories in the world, comprised of networks of sensors along the seafloor and throughout the ocean waters.
In November 2024, Oregon State University geophysicist William Chadwick started investigating the volcano when he noticed its surface had swelled to nearly the same height it reached before its last eruption 10 years ago
The volcano is located off the coast of Oregon. Pictured is a quaint town in the state
When Axial Seamount finally erupts, Wilcock and his colleagues will use this array to gather data and images of the event as it unfolds.
Even though Axial is not a dangerous undersea volcano, the forecasting capabilities scientists have gained from studying it could help them predict eruptions from those that are.
For example, in January 2022, an extremely powerful eruption of the Hunga underwater volcano in the Tonga archipelago in the southern Pacific Ocean triggered a tsunami that caused an estimated $90 billion in damages.
This massive wave impacted California, Hawaii, and parts of Canada, Chile, Fiji, Japan, New Zealand, Mexico and Peru.
The West Coast won’t have to worry about Axial causing an event like that. But its eruption will provide an opportunity for scientists to learn more about how these powerful geological structures work.
