QuakeIndex

Earthquake · reviewed by a seismologist

M 2.6md

Earthquake near San Pablo, CA

No earthquake was likely felt in San Pablo in the 24 hours to 3:33 am PST (11:33 UTC). The last one was M 1.6, 10 km (6 mi) WNW, at 11:44 am PST on 10 November 2026, estimated intensity II (weak) in town. Every earthquake near San Pablo

This page: a magnitude 2.6 earthquake was recorded in San Pablo, CA, at 1:44 am PST on 31 December 2020 (09:44 UTC), 4.9 km deep. 271 people have reported feeling it to USGS.

USGS: 0km E of San Pablo, CA

21 km (13 mi) NNE of San Francisco, CA · in Richmond, CA

1:44 am PST, Dec 31, 2020 · · 4.9 km deep · released about 240 lb of TNT

Every earthquake near San Pablo Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Contra Costa County 35 kmMarin County 37 kmSolano County 49 kmAlameda County 52 kmNapa County 61 kmSan Mateo County 61 kmSan Francisco County 66 kmSonoma County 81 kmYolo 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
1:44 am PST on 31 December 2020 ()
Where
in San Pablo, CA · earthquakes near San Pablo
Magnitude
M 2.6 (md)
Depth
4.9 km below the surface
Felt
271 reports · strongest reported intensity V
Nearest
Contra Costa County, 35 km E
Nearest mapped fault
Hayward fault, 13 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 1473 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 23 km (14 mi) from the epicentre. 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: San Pablo in town, intensity III · Richmond 3 km, intensity III · El Cerrito 6 km, intensity III · Pinole 6 km, intensity III · Hercules 8 km, intensity III · Berkeley 12 km, intensity II · Crockett 15 km, intensity II · San Rafael 17 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 240 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 63,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 45,000× the energy of this one
  3. Around the size people start to feel M 3.0 4× the energy of this one
  4. This earthquake M 2.6 about 240 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 620 times the energy of this one.

Before 2016, the USGS record lists 3 earthquakes of M5 or more within 50 km:

  1. 7.9 The 1906 San Francisco, California Earthquake · 30 km SW of this epicentre
  2. 6.0 The 2014 South Napa, California Earthquake · 28 km N of this epicentre
  3. 5.3 The 1957 San Francisco, California Earthquake · 35 km SSW 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 37.9625, -122.3432. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Contra Costa County, CA 35 km (22 mi) E earthquakes near Contra Costa County
Marin County, CA 37 km (23 mi) WNW earthquakes near Marin County
Solano County, CA 49 km (30 mi) NE earthquakes near Solano County
Alameda County, CA 52 km (32 mi) SE earthquakes near Alameda County
Napa County, CA 61 km (38 mi) N earthquakes near Napa County
San Mateo County, CA 61 km (38 mi) S earthquakes near San Mateo County

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

Aftershocks so far

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

  1. 2.8 2km N of Piedmont, CA
  2. 1.5 4km SW of Glen Ellen, CA
  3. 1.5 5km E of Vallejo, CA
  4. 2.5 2km N of Piedmont, CA
  5. 1.8 3km S of Concord, CA
  6. 2.3 6km WSW of Colma, CA
  7. 2.1 3km WNW of Pacifica, CA
  8. 1.6 6km ESE of Santa Venetia, CA
  9. 1.8 1km SW of East Richmond Heights, CA
  10. 2.4 0km W of Pleasant Hill, CA
  11. 1.6 5km S of Yountville, CA
  12. 2.7 10km WNW of American Canyon, CA
  13. 1.6 2km E of Vallejo, CA
  14. 1.7 6km SSW of Yountville, CA
  15. 1.9 3km ESE of Berkeley, 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.