QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4md

2 km N of Middletown, CA

· 4.7 km deep · released about 140 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Napa County 38 kmSonoma County 39 kmLake County 39 kmColusa County 56 kmYolo County 62 kmMarin County 81 kmSolano County 81 kmSutter County 84 kmGlenn County 94 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 2.4 (md)
Depth
4.7 km below the surface
Felt
3 reports · strongest reported intensity III
Nearest
Napa County, 38 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 17 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 3 people have reported feeling it to USGS.

How big was it?

This earthquake released about 140 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 110,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 78,000× the energy of this one
  3. Around the size people start to feel M 3.0 6.9× the energy of this one
  4. This earthquake M 2.4 about 140 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.

Where

Epicentre 38.7700, -122.6122. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Napa County, CA 38 km (24 mi) NW of here earthquakes near Napa County
Sonoma County, CA 39 km (24 mi) NE of here earthquakes near Sonoma County
Lake County, CA 39 km (24 mi) SSE of here earthquakes near Lake County
Colusa County, CA 56 km (35 mi) SW of here earthquakes near Colusa County
Yolo County, CA 62 km (39 mi) W of here earthquakes near Yolo County
Marin County, CA 81 km (50 mi) N of here earthquakes near Marin County

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

Aftershocks so far

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

  1. 1.7 8 km ESE of Cloverdale, CA
  2. 1.8 7 km WNW of Cobb, CA
  3. 1.8 7 km W of Saint Helena, CA
  4. 1.5 4 km W of Cobb, CA
  5. 1.8 8 km W of Saint Helena, CA
  6. 1.9 3 km ENE of The Geysers, CA
  7. 1.9 4 km ESE of Santa Rosa, CA
  8. 1.6 8 km NW of The Geysers, CA
  9. 1.6 3 km W of Anderson Springs, CA
  10. 1.6 4 km ESE of Santa Rosa, CA
  11. 2.7 3 km ESE of Santa Rosa, CA
  12. 1.7 8 km ESE of Cloverdale, CA
  13. 1.7 7 km W of Cobb, CA
  14. 1.6 1 km ESE of The Geysers, CA
  15. 1.6 5 km 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 7,200 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.