4.5-magnitude earthquake wakes up residents around western Washington

By Alex Didion, KING 5

ORCAS, Wash. (KGW/KTVZ) — A 4.5-magnitude earthquake struck in the waters surrounding Washington San Juan Islands early Monday morning.

The 4.5 magnitude earthquake hit at 5:02 a.m. just off Deer Beach on Orcas Island, according to the United States Geologic Survey. The quake was measured at a depth of 10.13 miles, per USGS data.

It was the region's largest earthquake since 2019, according to data from the Pacific Northwest Seismic Network.

The National Weather Service says there is no tsunami risk from this earthquake.

KING 5 viewers across western Washington reported being able to feel the earthquake in Oak Harbor, Mukilteo, Bow and Arlington.

Monday's earthquake comes after a variety of seismic events hit around the region in February, including a pair of earthquakes over 2.5 magnitude on Feb. 27.

PNSN Director Harold Tobin said this shows that Washington is in a seismically active region. 

“So far there’s nothing that rises above what I would call normal activity for our region,” Tobin said. “Sometimes we have bigger felt earthquakes. Sometimes we go a longer period without them.”

Earthquakes around western Washington

Many earthquakes in Washington state are linked to the motion of the Juan de Fuca Plate and the North American Continental Plate moving against each other as the Juan de Fuca Plate slips beneath the North American continent, according to PNSN. This is called the Cascadia Subduction Zone. 

According to the Washington State Department of Natural Resources (DNR), earthquakes happen in Washington every day, but most are too small to be felt. The state has the second highest risk in the U.S. of experiencing a large and damaging earthquake because of its geologic setting. 

The Pacific Northwest typically experiences three types of earthquakes: 

• Shallow fault quakes: Ruptures in faults located in the upper 18 miles of the Earth's crust. These earthquakes typically last 20 to 60 seconds and shaking is localized to the area near the fault, according to the DNR.  
• Deep earthquakes: Deep faults happen when two tectonic plates collide and one plate slips beneath the other one. These quakes can impact a large area but are less intense. 
• Subduction zone earthquakes: This earthquake results from the tension of an oceanic plate slipping beneath a continental plate. When enough stress builds, the fault will rupture, releasing a massive amount of energy. The Cascadia Subduction Zone has the potential for these types of earthquakes and has ruptured in the past. It is one of Washington state's biggest hazards, according to DNR.