M3.8 earthquake 39 km NNE of Spencer, Idaho

A magnitude 3.8 earthquake struck 39 km NNE of Spencer, Idaho on Thu, Nov 21, 1985, 8:34 AM MST (15:34 UTC), 5 km (3 mi) below the surface.

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: 71 in the 60 days after this one and 59 in the 30 days before it.

The first 60 of 71.

From the USGS Earthquake Hazards Program and its partner networks, event usp0002n0x. Read Tue, Sep 22, 2026, 10:25 PM UTC.