QuakeIndex

Earthquake · reviewed by a seismologist

M 2.2md

Earthquake near Calistoga, CA

No earthquake was likely felt in Calistoga in the 24 hours to 10:38 am PST (18:38 UTC). The last one was M 3.0, 33 km (21 mi) NW, at 11:06 pm PDT on 14 October 2026, estimated intensity II (weak) in town; 1 felt report to USGS. Every earthquake near Calistoga

This page: a magnitude 2.2 earthquake was recorded 13 km (8 mi) west-northwest of Calistoga, CA, at 3:13 pm PST on 26 February 2021 (23:13 UTC), 6.5 km deep. 1 person has reported feeling it to USGS.

USGS: 13km WNW of Calistoga, CA

21 km (13 mi) N of Santa Rosa, CA

3:13 pm PST, Feb 26, 2021 · · 6.5 km deep · released about 62 lb of TNT

10 km30 km60 km120 km N Sonoma County 23 kmNapa County 36 kmLake County 53 kmMarin County 65 kmYolo County 70 kmColusa County 73 kmSolano County 78 kmSutter County 97 kmContra Costa County 103 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
3:13 pm PST on 26 February 2021 ()
Where
13 km (8 mi) west-northwest of Calistoga, CA · earthquakes near Calistoga
Magnitude
M 2.2 (md)
Depth
6.5 km below the surface
Felt
1 report · strongest reported intensity III
Nearest
Sonoma County, 23 km WSW
Nearest mapped fault
Maacama fault, 4 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 2086 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 17 km (11 mi) from the epicentre. In Calistoga, 13 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: Calistoga 13 km, intensity II · Windsor 14 km, intensity II · Healdsburg 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 62 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 5.8 240,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 170,000× the energy of this one
  3. Around the size people start to feel M 3.0 15× the energy of this one
  4. This earthquake M 2.2 about 62 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 5.0 on 2016-12-14 — about 16,000 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 5.3 3 km E of Bloomfield, California · 37 km SSW of this epicentre
  2. 5.3 Northern California · 37 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 38.6357, -122.7048. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Sonoma County, CA 23 km (14 mi) WSW earthquakes near Sonoma County
Napa County, CA 36 km (22 mi) ESE earthquakes near Napa County
Lake County, CA 53 km (33 mi) N earthquakes near Lake County
Marin County, CA 65 km (40 mi) S earthquakes near Marin County
Yolo County, CA 70 km (43 mi) E earthquakes near Yolo County
Colusa County, CA 73 km (45 mi) NNE earthquakes near Colusa County

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

Aftershocks so far

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

  1. 2.0 4km SSW of Anderson Springs, CA
  2. 1.9 6km NW of The Geysers, CA
  3. 1.5 4km WNW of The Geysers, CA
  4. 1.7 6km WNW of Cobb, CA
  5. 2.2 6km WNW of Cobb, CA
  6. 1.9 4km SW of Anderson Springs, CA
  7. 1.8 6km WNW of The Geysers, CA
  8. 1.7 5km NW of The Geysers, CA
  9. 1.8 11km ENE of Yountville, CA
  10. 2.8 10km ENE of Yountville, CA
  11. 1.8 4km SSW of Anderson Springs, CA
  12. 2.2 4km SSW of Anderson Springs, CA
  13. 2.2 4km W of Cobb, CA
  14. 2.2 4km W of Cobb, CA
  15. 2.3 9km WNW of The Geysers, 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.