QuakeIndex

Earthquake · automatic estimate, may change

M 1.7md

Earthquake near San Rafael, CA

No earthquake was likely felt in San Rafael in the 24 hours to 8:33 pm PST (04:33 UTC). The last one was M 1.6, 7 km (4 mi) ENE, at 11:44 am PST on 10 November 2026, estimated intensity II (weak) in town. Every earthquake near San Rafael

This page: a magnitude 1.7 earthquake was recorded 3 km (2 mi) east-northeast of San Rafael, CA, at 10:41 pm PDT on 20 September 2026 (05:41 UTC), 11 km deep. The magnitude and location are an automatic first estimate and may change.

USGS: 3 km ENE of San Rafael, CA

23 km (15 mi) NNW of San Francisco, CA · in San Rafael, CA

10:41 pm PDT, Sep 20, 2026 · · 11 km deep · released about 10 lb of TNT

Every earthquake near San Rafael Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Marin County 23 kmContra Costa County 49 kmSan Francisco County 55 kmSolano County 59 kmNapa County 61 kmAlameda County 64 kmSan Mateo County 64 kmSonoma County 71 kmYolo County 94 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
10:41 pm PDT on 20 September 2026 ()
Where
3 km (2 mi) east-northeast of San Rafael, CA · earthquakes near San Rafael
Magnitude
M 1.7 (md)
Depth
11 km below the surface
Felt
no reports yet
Nearest
Marin County, 23 km WNW
Nearest mapped fault
San Andreas fault, 16 km from its surface trace — near is not the same as on
Status
Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS · we first saw it 52 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 6 km (4 mi) from the epicentre. In San Rafael, 3 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: San Rafael 3 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 10 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,500,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 92× the energy of this one
  4. This earthquake M 1.7 about 10 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 14,000 times the energy of this one.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

  1. 7.9 The 1906 San Francisco, California Earthquake · 26 km S of this epicentre
  2. 6.0 The 2014 South Napa, California Earthquake · 31 km NNE of this epicentre
  3. 5.3 The 1957 San Francisco, California Earthquake · 35 km S of this epicentre
  4. 5.3 3 km E of Bloomfield, California · 46 km NW of this epicentre
  5. 5.3 Northern California · 47 km NW 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 37.9805, -122.5005. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Marin County, CA 23 km (14 mi) WNW earthquakes near Marin County
Contra Costa County, CA 49 km (30 mi) E earthquakes near Contra Costa County
San Francisco County, CA 55 km (34 mi) WSW earthquakes near San Francisco County
Solano County, CA 59 km (36 mi) ENE earthquakes near Solano County
Napa County, CA 61 km (38 mi) NNE earthquakes near Napa County
Alameda County, CA 64 km (40 mi) SE earthquakes near Alameda County

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

Aftershocks so far

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

  1. 1.8 1 km WNW of Pleasant Hill, CA
  2. 1.8 6 km ENE of Vallejo, CA
  3. 1.2 2 km WSW of Danville, CA
  4. 1.1 5 km WNW of San Francisco Zoo, CA
  5. 2.5 2 km WNW of Concord, CA
  6. 1.6 3 km E of Berkeley, CA
  7. 2.6 3 km ESE of Berkeley, CA
  8. 2.1 3 km W of Concord, CA
  9. 1.6 0 km NW of Diablo, CA
  10. 1.5 3 km WSW of Daly City, CA
  11. 1.0 2 km NE of Pacifica, CA
  12. 2.7 2 km NE of Pacifica, CA
  13. 1.1 2 km SSW of Alamo, CA
  14. 2.0 7 km ENE of Vallejo, CA
  15. 1.0 6 km E of Oakland, 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.