M3.3 earthquake 3 km S of Spencer, Oklahoma

A magnitude 3.3 earthquake struck 3 km S of Spencer, Oklahoma on Thu, Mar 21, 2013, 10:56 AM CDT (15:56 UTC), 11 km (7 mi) below the surface.

A larger quake followed: M4.4 Oklahoma. This one was a foreshock.

Map

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

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

Felt (III) at Oklahoma City and Spencer and (II) at Choctaw. Also felt at Harrah and Norman.

ML 3.3 (TUL). Felt (III) at Oklahoma City and Spencer and (II) at Choctaw. Also felt at Harrah and Norman.

From the USGS event page for usb000fq9y. U.S. Geological Survey text and figures are in the public domain.

133 people reported to the USGS what they felt; the strongest reported shaking was IV, light shaking.

Reviewed by a seismologist.

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

Within 100 km, magnitude 1.5 and up: 54 in the 60 days after this one and 9 in the 30 days before it.

From the USGS Earthquake Hazards Program and its partner networks, event usb000fq9y. Read Sun, Oct 4, 2026, 9:24 AM UTC.