QuakeIndex

Earthquake · reviewed by a seismologist

M 2.2md

Earthquake near Green Valley, CA

No earthquake was likely felt in Green Valley in the 24 hours to 11:47 pm PST (07:47 UTC). The last one was M 1.8, 13 km (8 mi) S, at 11:09 am PST on 4 November 2026, estimated intensity II (weak) in town. Every earthquake near Green Valley

This page: a magnitude 2.2 earthquake was recorded 3 km (2 mi) southwest of Green Valley, CA, at 4:03 pm PST on 14 February 2021 (00:03 UTC), 11 km deep.

USGS: 3km SW of Green Valley, CA

13 km (8 mi) SE of Napa, CA · 54 km (34 mi) NNE of San Francisco, CA

4:03 pm PST, Feb 14, 2021 · · 11 km deep · released about 69 lb of TNT

10 km30 km60 km120 km N Solano County 22 kmNapa County 33 kmContra Costa County 40 kmMarin County 53 kmYolo County 55 kmAlameda County 69 kmSonoma County 73 kmSacramento County 77 kmSan Joaquin County 86 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
4:03 pm PST on 14 February 2021 ()
Where
3 km (2 mi) southwest of Green Valley, CA · earthquakes near Green Valley
Magnitude
M 2.2 (md)
Depth
11 km below the surface
Felt
no reports yet
Nearest
Solano County, 22 km E
Nearest mapped fault
Green Valley 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 2094 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 15 km (9 mi) from the epicentre. In Green Valley, 3 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: Napa 12 km, intensity II · Suisun 12 km, intensity II · Fairfield 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 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.

  1. Mineral, Virginia 2011 M 5.8 220,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 150,000× 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 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:

  1. 6.0 The 2014 South Napa, California Earthquake · 11 km W of this epicentre
  2. 5.4 South of Elmira, California · 26 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 38.2320, -122.1823. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Solano County, CA 22 km (13 mi) E earthquakes near Solano County
Napa County, CA 33 km (21 mi) NNW earthquakes near Napa County
Contra Costa County, CA 40 km (25 mi) SSE earthquakes near Contra Costa County
Marin County, CA 53 km (33 mi) WSW earthquakes near Marin County
Yolo County, CA 55 km (34 mi) NNE earthquakes near Yolo County
Alameda County, CA 69 km (43 mi) SSE earthquakes near Alameda County

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

Aftershocks so far

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

  1. 2.1 10km ESE of Angwin, CA
  2. 1.6 3km SSW of Clayton, CA
  3. 1.6 1km W of Alamo, CA
  4. 1.7 3km N of Piedmont, CA
  5. 2.4 2km ENE of Pacheco, CA
  6. 1.8 2km ENE of Oakland, CA
  7. 1.6 1km SW of Danville, CA
  8. 1.7 9km NNE of Yountville, CA
  9. 2.1 7km ESE of Roseland, CA
  10. 1.6 6km SE of St. Helena, CA
  11. 1.9 6km SW of Clayton, CA
  12. 1.7 2km ESE of Berkeley, CA
  13. 1.8 2km ESE of Berkeley, CA
  14. 2.0 6km S of Calistoga, CA
  15. 1.9 5km W of Glen Ellen, 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.