QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near San Francisco, CA

No earthquake was likely felt in San Francisco in the 24 hours to 6:31 pm PST (02:31 UTC). The last one was M 2.6, 18 km (11 mi) ENE, at 6:23 pm PST on 1 November 2026, estimated intensity II (weak) in town; 114 felt reports to USGS. Every earthquake near San Francisco

This page: a magnitude 1.8 earthquake was recorded 11 km (7 mi) southwest of San Francisco, CA, at 10:51 pm PDT on 3 September 2022 (05:51 UTC), 7.2 km deep. 2 people have reported feeling it to USGS.

USGS: 2km SW of San Francisco Zoo, CA

12 km (7 mi) SW of San Francisco, CA · 6 km (4 mi) WNW of Daly City, CA

10:51 pm PDT, Sep 3, 2022 · · 7.2 km deep · released about 16 lb of TNT

10 km30 km60 km120 km N San Mateo County 36 kmMarin County 42 kmSan Francisco County 45 kmAlameda County 55 kmContra Costa County 55 kmSolano County 80 kmNapa County 89 kmSanta Cruz County 91 kmSanta Clara County 92 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
10:51 pm PDT on 3 September 2022 ()
Where
11 km (7 mi) southwest of San Francisco, CA · earthquakes near San Francisco
Magnitude
M 1.8 (md)
Depth
7.2 km below the surface
Felt
2 reports · strongest reported intensity II
Nearest
San Mateo County, 36 km SSE
Nearest mapped fault
San Andreas fault, under 1 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1531 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 12 km (7 mi) from the epicentre. In San Francisco, 11 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

Likely felt in: Daly City 6 km, intensity II · San Francisco 11 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 16 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 930,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 660,000× the energy of this one
  3. Around the size people start to feel M 3.0 59× the energy of this one
  4. This earthquake M 1.8 about 16 lb of TNT

Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.

For this area

The largest earthquake within 50 km since 2016 was M 4.5 on 2019-10-15 — about 9,100 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 7.9 The 1906 San Francisco, California Earthquake · 4 km NNW of this epicentre
  2. 5.3 The 1957 San Francisco, California Earthquake · 7 km SSE of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 37.7183, -122.5257. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Mateo County, CA 36 km (23 mi) SSE earthquakes near San Mateo County
Marin County, CA 42 km (26 mi) NNW earthquakes near Marin County
San Francisco County, CA 45 km (28 mi) W earthquakes near San Francisco County
Alameda County, CA 55 km (34 mi) E earthquakes near Alameda County
Contra Costa County, CA 55 km (34 mi) ENE earthquakes near Contra Costa County
Solano County, CA 80 km (50 mi) NE earthquakes near Solano County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

38 earthquakes have been recorded within 50 km since this one.

  1. 1.8 4km WSW of San Francisco Zoo, CA
  2. 3.6 1km ENE of El Cerrito, CA
  3. 1.6 3km E of Oakland, CA
  4. 2.6 8km WSW of Muir Beach, CA
  5. 1.7 3km NW of Diablo, CA
  6. 2.1 2km E of Berkeley, CA
  7. 1.7 5km WNW of Dublin, CA
  8. 2.8 3km S of Half Moon Bay, CA
  9. 1.7 3km SW of El Cerrito, CA
  10. 2.7 2km SSW of Alamo, CA
  11. 1.6 2km W of Walnut Creek, CA
  12. 1.6 3km ESE of Berkeley, CA
  13. 1.5 3km N of Piedmont, CA
  14. 1.5 5km SSE of Rodeo, CA
  15. 2.1 1km WNW of Kensington, CA

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.