QuakeIndex

Earthquake · reviewed by a seismologist

M 2.2md

Earthquake near Alamo, CA

No earthquake was likely felt in Alamo in the 24 hours to 4:00 am PST (12:00 UTC). The last one was M 2.1, 11 km (7 mi) NNW, at 4:05 am PST on 8 November 2026, estimated intensity II (weak) in town; 3 felt reports to USGS. Every earthquake near Alamo

This page: a magnitude 2.2 earthquake was recorded 7 km (4 mi) northeast of Alamo, CA, at 7:22 pm PST on 13 February 2025 (03:22 UTC), 10 km deep. 3 people have reported feeling it to USGS.

USGS: 7 km NE of Alamo, CA

5 km (3 mi) E of Walnut Creek, CA · 40 km (25 mi) ENE of San Francisco, CA

7:22 pm PST, Feb 13, 2025 · · 10 km deep · released about 67 lb of TNT

10 km30 km60 km120 km N Contra Costa County 4 kmAlameda County 28 kmSolano County 42 kmSan Joaquin County 63 kmSan Mateo County 63 kmMarin County 69 kmNapa County 74 kmSanta Clara County 79 kmSacramento County 83 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
7:22 pm PST on 13 February 2025 ()
Where
7 km (4 mi) northeast of Alamo, CA · earthquakes near Alamo
Magnitude
M 2.2 (md)
Depth
10 km below the surface
Felt
3 reports · strongest reported intensity II
Nearest
Contra Costa County, 4 km NE
Nearest mapped fault
Greenville fault, 7 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 632 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 16 km (10 mi) from the epicentre. In Alamo, 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: Alamo 7 km, intensity II · Walnut Creek 7 km, intensity II · Danville 8 km, intensity II · Pleasant Hill 9 km, intensity II · Concord 10 km, intensity II · Lafayette 12 km, intensity II · San Ramon 13 km, intensity II · Pacheco 13 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 67 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 5.8 230,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 160,000× the energy of this one
  3. Around the size people start to feel M 3.0 14× the energy of this one
  4. This earthquake M 2.2 about 67 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 2,200 times the energy of this one.

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

  1. 6.0 The 2014 South Napa, California Earthquake · 46 km NW of this epicentre
  2. 5.8 The 1980 Livermore, California Earthquake · 20 km ESE of this epicentre
  3. 5.4 South of Elmira, California · 46 km N of this epicentre
  4. 5.4 9 km NE of Livermore, California · 29 km ESE of this epicentre
  5. 5.1 11 km E of Blackhawk, California · 20 km ESE 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 37.8943, -121.9830. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Contra Costa County, CA 4 km (2 mi) NE earthquakes near Contra Costa County
Alameda County, CA 28 km (18 mi) SSE earthquakes near Alameda County
Solano County, CA 42 km (26 mi) N earthquakes near Solano County
San Joaquin County, CA 63 km (39 mi) E earthquakes near San Joaquin County
San Mateo County, CA 63 km (39 mi) SSW earthquakes near San Mateo County
Marin County, CA 69 km (43 mi) WNW earthquakes near Marin 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. 1.9 1 km SSE of Walnut Creek, CA
  2. 1.5 8 km NNE of Benicia, CA
  3. 1.7 5 km W of Dublin, CA
  4. 1.9 8 km SW of Mountain House, CA
  5. 1.7 12 km W of Rio Vista, CA
  6. 1.6 12 km NE of Pittsburg, CA
  7. 2.9 13 km NNE of Pittsburg, CA
  8. 2.3 12 km NNE of Pittsburg, CA
  9. 2.1 12 km W of Rio Vista, CA
  10. 1.8 12 km W of Rio Vista, CA
  11. 2.7 3 km W of Orinda, CA
  12. 2.9 5 km WNW of Dublin, CA
  13. 1.7 9 km E of Blackhawk, CA
  14. 1.5 5 km E of Vallejo, CA
  15. 1.7 2 km ENE of Lafayette, 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.