Oregon's Hidden Giant: Underwater Volcano Ready to Rumble

A colossal volcano lurks beneath the Pacific, poised to erupt. Axial Seamount, roughly 300 miles off Oregon’s coast, is no ordinary volcano. It stands tall, nearly 3, 600 feet high, fueled by Earth's fiery mantle. This underwater giant sits atop the Juan de Fuca Ridge, where two massive tectonic plates slowly drift apart. This constant motion builds pressure, making Axial a hotspot for volcanic activity. Scientists are keeping a close eye on it. The University of Washington's Regional Cabled Array is the watchdog here. This advanced network of underwater sensors provides real-time data on seismic activity, temperature changes, and even live video feeds from the volcano’s surface. The array stretches from the Oregon coast to the summit of Axial Seamount. Marine geophysicist William Wilcock leads the charge, tracking the volcano's every move. He notes that Axial typically gives clear warnings before an eruption. As magma rises, small earthquakes increase around the seamount. Currently, about 200 to 300 tremors occur daily—far fewer than the thousands expected before an eruption. But Wilcock warns that the situation can change swiftly. "It could be tomorrow, " he cautions, highlighting the unpredictability of these events. When Axial Seamount last erupted in April 2015, scientists witnessed about 10, 000 small earthquakes signaling the start. The eruption lasted around a month, spreading lava across 25 miles of ocean floor. Each eruption dramatically reshapes the seafloor, often collapsing sections of the volcano's magma chamber and forming a crater known as a caldera. Debbie Kelley, who directs the monitoring program, describes these eruptions as mild compared to land-based volcanoes. "It’s like putting a mile of seawater on top of Kilauea volcano, " she explains. Instead of dramatic ash clouds, lava quietly oozes from cracks, rapidly cooling into new rock formations. Deep-water eruptions produce distinctive sounds that scientists detect with underwater microphones. "When seawater gets trapped beneath a lava flow, it heats up, turns to steam, and eventually bursts, " Wilcock explains. "That creates loud implosions we hear clearly. " Surprisingly, Axial’s violent transformations create some of Earth's richest deep-sea habitats. Its hydrothermal vents support vast communities of microbes, giant tubeworms, spider crabs, and even octopuses. "Life thrives in these inhospitable environments, " Kelley says. Each eruption temporarily destroys these unique communities, yet life returns within months, stronger and more diverse than ever. Researchers recently saw this rapid recovery during an expedition near Costa Rica. Scientists from Woods Hole Oceanographic Institution accidentally witnessed an active eruption while exploring deep-sea vents. The eruption charred marine life, but researchers expect recovery within months, similar to past observations at Axial. One unexpected discovery at Axial Seamount involves a mysterious connection between volcanic activity and celestial bodies. Every recorded eruption—in 1998, 2011, and 2015—occurred between January and April, as Earth moves farther from the sun. Marine geophysicist Maya Tolstoy from UW College of the Environment notes this might be linked to gravitational effects from the moon. As the moon's gravity causes tides to rise and fall, it also changes pressures on the seafloor, potentially triggering eruptions at critical times. "At high tide, ocean weight presses down on the crust, and during low tide, earthquake activity increases, " Tolstoy explains. Researchers eagerly await Axial’s next eruption to test these theories. Each volcanic event helps scientists better understand Earth's geological processes and the extreme habitats that surround these underwater mountains. The upcoming eruption promises a front-row seat like never before. The University of Washington's observatory plans to livestream the event worldwide—an unprecedented scientific broadcast. "Three-quarters of Earth's volcanic activity happens at mid-ocean ridges, " Kelley says. "Yet, we've never directly observed these eruptions in real-time. " Axial’s eruption poses no danger to coastal residents or marine animals. Instead, it offers scientists a unique opportunity to learn more about deep-sea geology and biology.