QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4md

Earthquake near San Francisco, CA

No earthquake was likely felt in San Francisco in the 24 hours to 7:22 am PST (15:22 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 2.4 earthquake was recorded 16 km (10 mi) west of San Francisco, CA, at 10:41 am PST on 15 February 2017 (18:41 UTC), 4.8 km deep. 3 people have reported feeling it to USGS.

USGS: 7 km S of Muir Beach, California

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

10:41 am PST, Feb 15, 2017 · · 4.8 km deep · released about 140 lb of TNT

10 km30 km60 km120 km N Marin County 31 kmSan Francisco County 39 kmSan Mateo County 47 kmContra Costa County 58 kmAlameda County 63 kmSolano County 78 kmNapa County 82 kmSonoma County 86 kmSanta Cruz County 102 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 am PST on 15 February 2017 ()
Where
16 km (10 mi) west of San Francisco, CA · earthquakes near San Francisco
Magnitude
M 2.4 (md)
Depth
4.8 km below the surface
Felt
3 reports · strongest reported intensity III
Nearest
Marin County, 31 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 3553 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 21 km (13 mi) from the epicentre. In San Francisco, 16 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 10 km, intensity II · Daly City 16 km, intensity II · San Francisco 16 km, intensity II · San Rafael 20 km, intensity II · Bayview-Hunters Point 21 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 140 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 110,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 78,000× the energy of this one
  3. Around the size people start to feel M 3.0 6.9× the energy of this one
  4. This earthquake M 2.4 about 140 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

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

  1. 7.9 The 1906 San Francisco, California Earthquake · 7 km SE of this epicentre
  2. 5.3 The 1957 San Francisco, California Earthquake · 18 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 37.7982, -122.5973. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Marin County, CA 31 km (19 mi) NNW earthquakes near Marin County
San Francisco County, CA 39 km (24 mi) WSW earthquakes near San Francisco County
San Mateo County, CA 47 km (29 mi) SSE earthquakes near San Mateo County
Contra Costa County, CA 58 km (36 mi) ENE earthquakes near Contra Costa County
Alameda County, CA 63 km (39 mi) ESE earthquakes near Alameda County
Solano County, CA 78 km (48 mi) NE earthquakes near Solano County

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

Aftershocks so far

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

  1. 2.0 2 km SW of Alamo, California
  2. 1.8 1 km NNW of Pleasant Hill, California
  3. 1.7 4 km NNW of Orinda, California
  4. 2.6 2 km ESE of Berkeley, California
  5. 1.9 4 km NNW of Orinda, California
  6. 1.5 Northern California
  7. 1.7 4 km W of Woodside, California
  8. 1.6 4 km SE of Piedmont, California
  9. 1.5 9 km ESE of Black Point-Green Point, California
  10. 2.2 7 km S of Muir Beach, California
  11. 2.9 7 km SSW of Muir Beach, California
  12. 1.9 0 km NNW of Pleasant Hill, California
  13. 2.0 0 km W of Kensington, California
  14. 1.7 0 km W of Kensington, California
  15. 1.8 0 km E of Hayward, California

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.