M4.2 earthquake 38 km SSE of Morton, Washington

A magnitude 4.2 earthquake struck 38 km SSE of Morton, Washington on Mon, Mar 31, 1980, 11:29 AM PST (19:29 UTC), -1 km (0 mi) below the surface.

A larger quake followed: M5.7 38 km NNE of Amboy, Washington. This one was a foreshock.

Map

Where this earthquake was located, with the others nearby. Select one for its page.

No one has reported feeling this quake to the USGS.

Reviewed by a seismologist.

Distance and direction from each place to the epicenter, with its forecast.

Within 100 km, magnitude 1.5 and up: at least 200 in the 60 days after this one and 137 in the 30 days before it.

The first 60 of at least 200.

From the USGS Earthquake Hazards Program and its partner networks, event uw10079633 (also filed as usp00016cq). Read Thu, Sep 24, 2026, 3:40 PM UTC.