QuakeIndex

Earthquake · reviewed by a seismologist

M 2.6md

Earthquake near San Francisco, CA

No earthquake was likely felt in San Francisco in the 24 hours to 12:06 pm PST (20:06 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 2.6 earthquake was recorded 17 km (10 mi) west of San Francisco, CA, at 11:25 pm PDT on 21 October 2022 (06:25 UTC), 4.8 km deep. 79 people have reported feeling it to USGS.

USGS: 7km SSW of Muir Beach, CA

17 km (10 mi) W of San Francisco, CA

11:25 pm PDT, Oct 21, 2022 · · 4.8 km deep · released about 220 lb of TNT

10 km30 km60 km120 km N Marin County 30 kmSan Francisco County 38 kmSan Mateo County 48 kmContra Costa County 59 kmAlameda County 64 kmSolano County 78 kmNapa County 82 kmSonoma County 85 kmSanta Cruz County 103 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
11:25 pm PDT on 21 October 2022 ()
Where
17 km (10 mi) west of San Francisco, CA · earthquakes near San Francisco
Magnitude
M 2.6 (md)
Depth
4.8 km below the surface
Felt
79 reports · strongest reported intensity IV
Nearest
Marin County, 30 km NNW
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 1409 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 23 km (14 mi) from the epicentre. In San Francisco, 17 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: Tamalpais-Homestead Valley 11 km, intensity II · Daly City 17 km, intensity II · San Francisco 17 km, intensity II · San Rafael 20 km, intensity II · Bayview-Hunters Point 22 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 220 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 70,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 50,000× the energy of this one
  3. Around the size people start to feel M 3.0 4.4× the energy of this one
  4. This earthquake M 2.6 about 220 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 4.4 on 2018-01-04 — about 520 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 · 8 km SE of this epicentre
  2. 5.3 The 1957 San Francisco, California Earthquake · 19 km SE 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 37.8022, -122.6080. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Marin County, CA 30 km (19 mi) NNW earthquakes near Marin County
San Francisco County, CA 38 km (24 mi) WSW earthquakes near San Francisco County
San Mateo County, CA 48 km (30 mi) SSE earthquakes near San Mateo County
Contra Costa County, CA 59 km (37 mi) ENE earthquakes near Contra Costa County
Alameda County, CA 64 km (39 mi) ESE earthquakes near Alameda County
Solano County, CA 78 km (49 mi) NE earthquakes near Solano County

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

Aftershocks so far

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

  1. 2.3 3km NNW of Lafayette, CA
  2. 2.1 0km SSW of Crockett, CA
  3. 1.7 10km WNW of San Francisco Zoo, CA
  4. 1.9 3km W of Orinda, CA
  5. 1.6 6km E of Santa Venetia, CA
  6. 1.9 1km S of Crockett, CA
  7. 1.8 3km NNW of Emeryville, CA
  8. 2.1 1km N of El Cerrito, CA
  9. 1.9 1km SSE of Crockett, CA
  10. 1.5 0km W of Kensington, CA
  11. 1.6 2km S of Oakland, CA
  12. 2.0 2km ESE of Berkeley, CA
  13. 1.7 5km SE of Point Reyes Station, CA
  14. 2.2 4km WSW of Colma, CA
  15. 1.8 5km WSW of Colma, 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.