M3.0 earthquake 4km SW of Redlands, CA

A magnitude 3.0 earthquake struck 4km SW of Redlands, CA on Fri, Jul 30, 2021, 5:59 PM PDT (00:59 UTC), 15 km (9 mi) below the surface.

A larger quake followed: M4.3 2km E of Carson, CA. 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
3.05	ML, local (Richter)	Southern California Seismic Network	Preferred · Final · ±0.137 · 199 stations
2.8	ML, local (Richter)	USGS National Earthquake Information Center	Reviewed · ±0.037 · 98 stations

The USGS ShakeMap: shaking estimated from seismic stations and the quake’s size, on the Modified Mercalli intensity scale.

153 people reported to the USGS what they felt; the strongest reported shaking was III, weak 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: 116 in the 60 days after this one and 54 in the 30 days before it.

The first 60 of 116.

From the USGS Earthquake Hazards Program and its partner networks, event ci39759175 (also filed as us6000f0v7). Read Sun, Oct 4, 2026, 2:38 PM UTC.