M3.2 earthquake 37 km NNE of Amboy, Washington

A magnitude 3.2 earthquake struck 37 km NNE of Amboy, Washington on Sun, Aug 20, 2006, 11:23 PM PDT (06:23 UTC), -2 km (-1 mi) below the surface.

A larger quake followed: M4.5 27 km NNE of Packwood, Washington. This one was a foreshock.

Map

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

Different scales measure different things and differ by a few tenths. The USGS marks one as preferred, and it is the one this page uses.

Mag.	Scale	Computed by	Notes
3.2	Md, duration	Pacific Northwest Seismic Network	Preferred · Final · ±0.04 · 6 stations
3.2	Md, duration	USGS National Earthquake Information Center	Reviewed

The USGS’s account of the effects of this earthquake.

no people dead or missing; no people injured; no buildings damaged or destroyed

From the USGS event page for uw10704358. U.S. Geological Survey text and figures are in the public domain.

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: 172 in the 60 days after this one and 125 in the 30 days before it.

The first 60 of 172.

From the USGS Earthquake Hazards Program and its partner networks, event uw10704358 (also filed as usp000ere6). Read Sat, Oct 3, 2026, 8:28 AM UTC.