The most active volcano in the Pacific Northwest is the Axial Seamount. It鈥檚 located 300 miles west of Astoria, Oregon, and a mile under the ocean. It鈥檚 erupted three times in the past 25 years.
And now after a few years of relative slumber, the undersea volcano again. Data collected on Axial show the magma chamber is filling up and hundreds of small earthquakes are happening in the area each day.
鈥淎xial is the most active volcano in the Northeast Pacific, which maybe some people don鈥檛 know because it鈥檚 hidden under the ocean,鈥� said volcanologist Bill Chadwick. 鈥淚t鈥檚 actually more active than any of the volcanoes we鈥檙e familiar with, like 鈥� Mount St. Helens, Mount Hood, Mount Rainier.鈥�
Chadwick and his colleagues have been studying the Axial Seamount for decades, every couple of years to collect data from instruments on the seafloor.
The Axial Seamount is a 鈥� like you鈥檇 find in Hawaii or Iceland 鈥� meaning it doesn鈥檛 blow its top when it erupts. Instead the magma below causes it to crack open on its slopes and ooze syrupy lava.
鈥淚t doesn鈥檛 have that flashy, 鈥楢xial鈥檚 gonna erupt and cause a tsunami,鈥欌�� said Jeff Beeson, a geologist at Oregon State University. 鈥淚t鈥檚 not happening. [The volcano is] not going to erupt and have a lava flow that goes into someone鈥檚 backyard.鈥�
But because Axial is so active, it鈥檚 extremely valuable for scientists who are trying to learn about volcanoes.
鈥淲e鈥檙e trying to understand how it evolves over time. How the magma moves leading up to an eruption and during an eruption. What happens right after an eruption? These are things that are not really that well understood about volcanoes in general,鈥� said Chadwick鈥檚 research partner Scott Nooner, a geophysicist at the .
They鈥檙e also trying to figure out how to accurately forecast when volcanoes will erupt.
The last time the Axial Seamount erupted was in 2015. Almost immediately after the eruption, scientific instruments around the volcano showed that the surface was rising up, inflating like a balloon, an indication that . And so it looked as if the volcano was heading towards another eruption.
Seeing this rapid inflation, Chadwick predicted that the volcano would erupt between 2020 and 2024. But almost immediately after he published that prediction, Axial seemed to change its mind. Chadwick says the rate of magma buildup 鈥渟lowed way down.鈥� And Axial has not erupted again.
鈥淚t鈥檚 always going to be somewhat of a challenge to really know what鈥檚 happening underground where you can鈥檛 see it,鈥� Chadwick said.
But this past January, things started to change again. Data collected by the (a permanent cable running from Pacific City, Oregon, out to the Axial Seamount) indicates the rate of seafloor inflation has nearly doubled.
Visualization of the Axial Seamount, an active volcano off the Oregon Coast.NOAAIn addition, at the have observed the happening around Axial has increased significantly. Before the eruption in 2015, researchers saw the number of earthquakes skyrocket.
鈥淐omparing this to the buildup to the 2015 eruption 鈥� suggests we may be getting close to being in a comparable buildup stage,鈥� Chadwick wrote in his .
Based on what he鈥檚 seeing, Chadwick says he has a new and 鈥渨ildly optimistic鈥� Axial eruption forecast: sometime in 2025 or 2026.
鈥淎t a real dangerous volcano, you don鈥檛 want to be issuing any predictions that you鈥檙e not sure are going to be true, because people might have to evacuate. There could be economic costs and freaking people out,鈥� he says.
But at the natural laboratory that is the Axial Seamount, Chadwick has the latitude to experiment.
鈥淗ere, there鈥檚 just a bunch of tube worms and octopus on the seafloor. They don鈥檛 care.鈥� he laughs. 鈥淭hey don鈥檛 read the newspaper.鈥�
At Axial, he can try to figure out ways to accurately forecast volcanic eruptions that could eventually be used to make life-saving predictions when it counts.
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