QuakeIndex

Earthquake · reviewed by a seismologist

M 3.3ml

6km S of Calistoga, CA

· 9.1 km deep · released about 1.2 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Napa County 23 kmSonoma County 30 kmMarin County 54 kmYolo County 62 kmSolano County 63 kmLake County 67 kmColusa County 79 kmContra Costa County 87 kmSutter County 95 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
Magnitude
M 3.3 (ml)
Depth
9.1 km below the surface
Felt
262 reports · strongest reported intensity III
Nearest
Napa County, 23 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1860 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 262 people have reported feeling it to USGS.

How big was it?

This earthquake released about 1.2 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.3 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 140,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 6,500× the energy of this one
  3. Magna, Utah 2020 M 5.7 4,600× the energy of this one
  4. This earthquake M 3.3 about 1.2 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 2.5× more

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.

Where

Epicentre 38.5227, -122.5848. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Napa County, CA 23 km (14 mi) W of here earthquakes near Napa County
Sonoma County, CA 30 km (18 mi) E of here earthquakes near Sonoma County
Marin County, CA 54 km (34 mi) NNE of here earthquakes near Marin County
Yolo County, CA 62 km (38 mi) WSW of here earthquakes near Yolo County
Solano County, CA 63 km (39 mi) WNW of here earthquakes near Solano County
Lake County, CA 67 km (41 mi) SSE of here earthquakes near Lake County

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

Aftershocks so far

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

  1. 2.0 5km NNW of The Geysers, CA
  2. 1.6 6km NW of The Geysers, CA
  3. 3.1 2km SSW of Anderson Springs, CA
  4. 1.7 6km NW of The Geysers, CA
  5. 2.3 1km NNW of The Geysers, CA
  6. 1.7 8km NW of The Geysers, CA
  7. 2.6 3km WSW of Anderson Springs, CA
  8. 1.8 6km NNW of The Geysers, CA
  9. 1.5 6km WNW of The Geysers, CA
  10. 1.8 7km NW of The Geysers, CA
  11. 2.8 1km W of Anderson Springs, CA
  12. 1.6 4km W of Kenwood, CA
  13. 1.6 6km WNW of Cobb, CA
  14. 2.4 2km NE of Anderson Springs, CA
  15. 2.5 6km NW 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.

For this area

The largest earthquake within 50 km in our catalogue was M 5.0 on 2016-12-14 — it released about 420 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.