Two major earthquakes struck off the coast of Oregon on Wednesday, just miles from the summit of Axial Seamount, a massive underwater volcano expected to erupt soon.

Experts have raised alarms as the Axial Seamount, a massive underwater volcano in the Pacific Northwest, experiences an unprecedented 2,000 earthquakes in a single day, signaling a potential eruption.

Deep in the Pacific Ocean, about 300 miles off the coast of Oregon, the Axial Seamount—one of the world’s most closely studied underwater volcanoes—is showing signs of an imminent eruption.