M3.5 earthquake 17km NW of San Simeon, CA

A magnitude 3.5 earthquake struck 17km NW of San Simeon, CA on Mon, Oct 25, 2021, 4:49 PM PDT (23:49 UTC), 6 km (4 mi) below the surface.

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
3.53	ML, local (Richter)	Northern California Seismic System	Preferred · Final · ±0.125 · 134 stations
3.2	ML, local (Richter)	USGS National Earthquake Information Center	Reviewed · ±0.043 · 70 stations

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

35 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: 86 in the 60 days after this one and 39 in the 30 days before it.

The first 60 of 86.

From the USGS Earthquake Hazards Program and its partner networks, event nc73644635 (also filed as us6000fxi8). Read Sun, Oct 4, 2026, 4:50 AM UTC.