M2.7 earthquake 3 km SSE of Union City, Oklahoma

A magnitude 2.7 earthquake struck 3 km SSE of Union City, Oklahoma on Tue, Apr 6, 2021, 1:46 AM CDT (06:46 UTC), 7 km (4 mi) below the surface.

A larger quake followed: M3.5 8 km SW of Dibble, Oklahoma. 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
2.66	ML, local (Richter)	Oklahoma Geological Survey	Preferred · Confirmed · ±0.26 · 29 stations
2.8	mb_Lg, Lg-wave body	USGS National Earthquake Information Center	Reviewed · ±0.051 · 101 stations

17 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 51 in the 30 days before it.

From the USGS Earthquake Hazards Program and its partner networks, event ok2021gscf (also filed as us6000dzch). Read Thu, Oct 1, 2026, 7:04 AM UTC.