M4.0 earthquake 13km SW of Olancha, CA

A magnitude 4.0 earthquake struck 13km SW of Olancha, CA on Sat, Jan 16, 2021, 6:49 PM PST (02:49 UTC), 1 km (1 mi) below the surface.

A larger quake followed: M4.0 10km SE of Olancha, 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
4.02	Mw, moment	Southern California Seismic Network	Preferred · Final · 6 stations
4.0	Mwr, regional moment	USGS National Earthquake Information Center	Reviewed · ±0.028 · 120 stations

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

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

The USGS PAGER system estimates deaths and economic losses from the shaking and the population and buildings exposed to it.

Reviewed by a seismologist.

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

Within 100 km, magnitude 1.5 and up: 198 in the 60 days after this one and 84 in the 30 days before it.

The first 60 of 198.

From the USGS Earthquake Hazards Program and its partner networks, event ci39759376 (also filed as us7000d0rv). Read Sun, Oct 4, 2026, 3:06 PM UTC.