QuakeIndex

Earthquake · reviewed by a seismologist

M 2.2md

Earthquake near Alameda, CA

No earthquake was likely felt in Alameda in the 24 hours to 4:59 pm PST (00:59 UTC). The last one was M 2.6, 11 km (7 mi) N, at 6:23 pm PST on 1 November 2026, estimated intensity II (weak) in town; 114 felt reports to USGS. Every earthquake near Alameda

This page: a magnitude 2.2 earthquake was recorded 7 km (4 mi) south of Alameda, CA, at 4:54 am PST on 1 February 2024 (12:54 UTC), 15 km deep. 3 people have reported feeling it to USGS.

USGS: 6 km S of Alameda, CA

7 km (4 mi) SSW of Oakland, CA · in Alameda, CA

4:54 am PST, Feb 1, 2024 · · 15 km deep · released about 56 lb of TNT

10 km30 km60 km120 km N Alameda County 31 kmContra Costa County 35 kmSan Mateo County 35 kmMarin County 58 kmSolano County 67 kmSan Francisco County 69 kmSanta Clara County 74 kmSanta Cruz County 81 kmNapa County 89 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
4:54 am PST on 1 February 2024 ()
Where
7 km (4 mi) south of Alameda, CA · earthquakes near Alameda
Magnitude
M 2.2 (md)
Depth
15 km below the surface
Felt
3 reports · strongest reported intensity III
Nearest
Alameda County, 31 km ESE
Nearest mapped fault
Hayward fault, 9 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 1003 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 10 km (6 mi) from the epicentre. In Alameda, 7 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: Alameda 7 km, intensity II · San Leandro 8 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 56 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.

  1. Mineral, Virginia 2011 M 5.8 270,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 190,000× the energy of this one
  3. Around the size people start to feel M 3.0 17× the energy of this one
  4. This earthquake M 2.2 about 56 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 2,600 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 · 27 km W of this epicentre
  2. 5.8 The 1980 Livermore, California Earthquake · 45 km ENE of this epicentre
  3. 5.4 9 km NE of Livermore, California · 48 km E of this epicentre
  4. 5.3 The 1957 San Francisco, California Earthquake · 21 km WSW of this epicentre
  5. 5.1 11 km E of Blackhawk, California · 43 km ENE 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 37.7132, -122.2490. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Alameda County, CA 31 km (19 mi) ESE earthquakes near Alameda County
Contra Costa County, CA 35 km (22 mi) NE earthquakes near Contra Costa County
San Mateo County, CA 35 km (22 mi) SSW earthquakes near San Mateo County
Marin County, CA 58 km (36 mi) NW earthquakes near Marin County
Solano County, CA 67 km (42 mi) NNE earthquakes near Solano County
San Francisco County, CA 69 km (43 mi) W earthquakes near San Francisco County

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

Aftershocks so far

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

  1. 1.7 3 km E of Alamo, CA
  2. 1.5 4 km WSW of San Francisco Zoo, CA
  3. 2.1 8 km WNW of San Francisco Zoo, CA
  4. 1.7 5 km E of Vallejo, CA
  5. 1.6 2 km N of Livermore, CA
  6. 1.7 1 km NNW of Orinda, CA
  7. 1.8 1 km NNW of Orinda, CA
  8. 1.7 7 km SSW of Muir Beach, CA
  9. 1.6 6 km ENE of Vallejo, CA
  10. 2.1 3 km ESE of Berkeley, CA
  11. 2.2 7 km SSW of Muir Beach, CA
  12. 1.8 10 km ENE of Blackhawk, CA
  13. 1.8 10 km SSW of Brentwood, CA
  14. 1.9 3 km ESE of Berkeley, CA
  15. 1.5 6 km E of Walnut Creek, 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.