QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5md

Earthquake near Colma, CA

No earthquake was likely felt in Colma in the 24 hours to 5:25 am PST (13:25 UTC). The last one was M 2.7, 6 km (4 mi) S, at 5:17 pm PDT on 28 October 2026, estimated intensity III (weak) in town; 526 felt reports to USGS. Every earthquake near Colma

This page: a magnitude 1.5 earthquake was recorded 4 km (2 mi) west-southwest of Colma, CA, at 4:29 pm PST on 12 January 2022 (00:29 UTC), 8.9 km deep.

USGS: 4km WSW of Colma, CA

14 km (9 mi) SSW of San Francisco, CA · 5 km (3 mi) SW of Daly City, CA

4:29 pm PST, Jan 12, 2022 · · 8.9 km deep · released about 5.7 lb of TNT

10 km30 km60 km120 km N San Mateo County 30 kmSan Francisco County 47 kmMarin County 48 kmAlameda County 52 kmContra Costa County 56 kmSolano County 83 kmSanta Cruz County 85 kmSanta Clara County 87 kmNapa County 95 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
4:29 pm PST on 12 January 2022 ()
Where
4 km (2 mi) west-southwest of Colma, CA · earthquakes near Colma
Magnitude
M 1.5 (md)
Depth
8.9 km below the surface
Felt
no reports yet
Nearest
San Mateo County, 30 km SSE
Nearest mapped fault
San Andreas fault, 2 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 1757 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 5 km (3 mi) from the epicentre. In Colma, 4 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.

Earthquakes near other towns within 30 km: Broadmoor, Daly City, Pacifica, South San Francisco, San Bruno, Brisbane.

How big was it?

This earthquake released about 5.7 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,900,000× the energy of this one
  3. Around the size people start to feel M 3.0 170× the energy of this one
  4. This earthquake M 1.5 about 5.7 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 26,000 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 · 10 km NNW of this epicentre
  2. 5.3 The 1957 San Francisco, California Earthquake · 2 km E 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 37.6665, -122.5007. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Mateo County, CA 30 km (19 mi) SSE earthquakes near San Mateo County
San Francisco County, CA 47 km (29 mi) W earthquakes near San Francisco County
Marin County, CA 48 km (30 mi) NNW earthquakes near Marin County
Alameda County, CA 52 km (32 mi) E earthquakes near Alameda County
Contra Costa County, CA 56 km (35 mi) ENE earthquakes near Contra Costa County
Solano County, CA 83 km (52 mi) NE earthquakes near Solano County

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

Aftershocks so far

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

  1. 1.5 2km NE of San Ramon, CA
  2. 1.8 2km SE of Danville, CA
  3. 2.1 1km E of Piedmont, CA
  4. 1.8 3km NNE of San Ramon, CA
  5. 2.0 4km SSE of Highlands-Baywood Park, CA
  6. 1.9 2km N of Castro Valley, CA
  7. 1.9 5km ESE of Moraga, CA
  8. 1.6 4km SW of San Ramon, CA
  9. 1.6 4km SW of San Ramon, CA
  10. 1.6 7km S of Muir Beach, CA
  11. 1.8 3km SW of San Francisco Zoo, CA
  12. 2.1 3km NE of Berkeley, CA
  13. 2.0 2km E of Hayward, CA
  14. 1.6 2km E of Hayward, CA
  15. 1.6 2km ESE of Hayward, 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.