This story was originally published on MyNorthwest.com.
Eighteen small- to mid-sized earthquakes were recorded off the coast of Washington on Sunday.
The earthquakes were recorded over several hours early in the morning, with the largest being roughly 240 miles west of Westport at a magnitude of 4.2, and a depth of 10 kilometers just before 5 a.m., according to the U.S. Geological Survey (USGS).
All 18 Sunday morning earthquakes remained in the 2-4 magnitude range, which is quite common over the course of a year. Michigan Tech estimated that millions of earthquakes magnitude 2.5 or less are recorded annually, and roughly 500,000 earthquakes occur between magnitudes 2.5 and 5.4.
A vast majority of the 2.5 or less magnitude earthquakes are not felt, but do show up on a seismograph, while the 2.5 to 5.4 magnitude quakes are often felt and tend to cause minor damage.
Earthquakes don’t pose threat to PNW onshore region
Seismologist and director of the Pacific Northwest Seismic Network, Harold Tobin, told The Seattle Times that this collection of earthquakes is nothing to worry about.
“These types of earthquakes don’t create a tsunami hazard,” he said. “They’re, first of all, just not big enough.”
The Pacific Northwest Seismic Network (PNSN) noted the USGS locations indicated that the earthquakes were “NOT anywhere near the Cascadia Subduction Zone, and do not signify anything about potential earthquakes there.”
“They are also not at the Axial Seamount Volcano, which has been predicted by others to be nearing an undersea eruption, though they are farther north along the same ridge,” PNSN stated. “This swarm does NOT pose a hazard to the PNW onshore region.”
Tobin explained that the Juan de Fuca plate is spreading apart from the Pacific plate, which is creating new crust of the Earth.
“It’s just a real sign that the tectonic plates are moving and active,” he told The Seattle Times.
©2026 Cox Media Group
