UW: Underwater volcano off Oregon coast could erupt any day

An underwater volcano 300 miles off the coast of Oregon is displaying signs of a potential eruption, University of Washington (UW) researchers found.

The volcano, Axial Seamount, is more than 4,900 feet below the surface of the Pacific Ocean. Axial Seamount is approximately 3,600 feet tall, and hasn’t erupted since 2015.

“Over two-thirds of the Earth’s surface was formed by volcanic eruptions at these mid-ocean ridges,” said Maya Tolstoy, a marine geophysicist and Maggie Walker Dean of the UW College of the Environment. “So the volcano is formed by these really fundamental processes that shape our planet.”

Axial Seamount, located on the Juan de Fuca Ridge, is formed by a hot spot—an area in the Earth’s mantle where hot plumes of molten material rise into the crust, according to the UW College of the Environment.

UW cited two reasons for believing an eruption is near: The way the volcano is inflating due to magma buildup beneath the surface, and the frequency of earthquakes coming from beneath the seafloor.

“Over time, the volcano inflates due to the buildup of magma beneath the surface,” William Wilcock, a professor in the UW School of Oceanography, said. “Some researchers have hypothesized that the amount of inflation can predict when the volcano will erupt, and if they’re correct, it’s very exciting for us, because it has already inflated to the level that it reached before the last three eruptions. That means it could really erupt any day now, if the hypothesis is correct.”

An eruption from Axial Seamount is not dangerous

Axial Seamount is both too deep and too far from shore for people to feel or notice when it erupts. UW stated residents of the Pacific Northwest shouldn’t worry about an eruption triggering a major earthquake or tsunami.

“Three-quarters of all of the volcanic activity on Earth takes place at mid-ocean spreading centers,” Deborah Kelley, a professor in the UW School of Oceanography, said. “But people have never directly witnessed an eruption along this mountain chain, so we still have a lot of unanswered questions.”

UW researchers are gearing up to study the unique habitats volcanoes create for sea creatures. The Axial Seamount volcano is home to many species of microbes and marine animals, many of them using the volcano’s hydrothermal vents as an “underwater hot spring,” where seawater migrates deep into the seafloor, is heated by magma, and then ejected back out in superheated, mineral-rich plumes. Many of these sea creatures use dissolved volcanic gases as a source of energy instead of sunlight.