Earthquake · reviewed by a seismologist
M 2.2md
Earthquake near Colma, CA
No earthquake was likely felt in Colma in the 24 hours to 12:52 am PST (08:52 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 2.2 earthquake was recorded 4 km (3 mi) west-southwest of Colma, CA, at 3:23 pm PST on 3 February 2023 (23:23 UTC), 5.5 km deep. 36 people have reported feeling it to USGS.
USGS: 4km WSW of Colma, CA
15 km (9 mi) SSW of San Francisco, CA · 5 km (3 mi) SW of Daly City, CA
- When
- 3:23 pm PST on 3 February 2023 ()
- Where
- 4 km (3 mi) west-southwest of Colma, CA · earthquakes near Colma
- Magnitude
- M 2.2 (md)
- Depth
- 5.5 km below the surface
- Felt
- 36 reports · strongest reported intensity III
- 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 1371 days ago
Earthquake alerts for Colma, CA
Get a notification in this browser when USGS records an earthquake near Colma, CA. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
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 18 km (11 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.
Likely felt in: Daly City 6 km, intensity II · Pacifica 6 km, intensity II · South San Francisco 9 km, intensity II · San Bruno 9 km, intensity II · Millbrae 13 km, intensity II · Bayview-Hunters Point 13 km, intensity II · San Francisco 14 km, intensity II · Burlingame 15 km, intensity II. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 69 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.2 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 220,000× the energy of this one
- Magna, Utah 2020 M 5.7 150,000× the energy of this one
- Around the size people start to feel M 3.0 14× the energy of this one
- This earthquake M 2.2 about 69 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 2,100 times the energy of this one.
Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:
- 7.9 The 1906 San Francisco, California Earthquake · 10 km NNW of this epicentre
- 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 37.6667, -122.5068. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction 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 (33 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
52 earthquakes have been recorded within 50 km since this one.
- 1.6 4km E of Berkeley, CA
- 1.6 4km WNW of San Francisco Zoo, CA
- 1.6 7km S of Muir Beach, CA
- 2.0 3km SSW of Port Costa, CA
- 2.1 1km WNW of Kensington, CA
- 1.7 2km ENE of Berkeley, CA
- 2.0 7km SSE of Portola Valley, CA
- 2.0 2km SE of Portola Valley, CA
- 1.9 7km SSE of Portola Valley, CA
- 2.1 7km SSE of Portola Valley, CA
- 2.4 1km N of Pacifica, CA
- 2.1 5km W of Hillsborough, CA
- 1.8 2km N of Lafayette, CA
- 2.2 5km WSW of San Francisco Zoo, CA
- 1.8 4km SSE of Highlands-Baywood Park, 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
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.