M3.5 earthquake 10km W of Delta, B.C., MX

A magnitude 3.5 earthquake struck 10km W of Delta, B.C., MX on Fri, Aug 6, 2021, 6:17 PM PDT (01:17 UTC), 20 km (12 mi) below the surface.

A larger quake followed: M4.0 12km N of Westmorland, 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
3.45	Mlr	Southern California Seismic Network	Preferred · Final · ±0.205 · 226 stations
3.5	ML, local (Richter)	USGS National Earthquake Information Center	Reviewed · ±0.059 · 38 stations

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

1 person 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: 96 in the 60 days after this one and 74 in the 30 days before it.

The first 60 of 96.

From the USGS Earthquake Hazards Program and its partner networks, event ci39766271 (also filed as us6000f327). Read Sun, Oct 4, 2026, 7:48 PM UTC.