QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

6km W of Glen Ellen, CA

· 8.9 km deep · released about 14 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Napa County 28 kmSonoma County 34 kmMarin County 38 kmSolano County 58 kmYolo County 69 kmContra Costa County 75 kmSan Francisco County 81 kmLake County 83 kmColusa 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 1.8 (md)
Depth
8.9 km below the surface
Felt
no reports yet
Nearest
Napa County, 28 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1592 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 14 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 790,000× the energy of this one
  3. Around the size people start to feel M 3.0 70× the energy of this one
  4. This earthquake M 1.8 about 14 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 38.3712, -122.5940. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Napa County, CA 28 km (17 mi) WSW of here earthquakes near Napa County
Sonoma County, CA 34 km (21 mi) ESE of here earthquakes near Sonoma County
Marin County, CA 38 km (24 mi) NNE of here earthquakes near Marin County
Solano County, CA 58 km (36 mi) WNW of here earthquakes near Solano County
Yolo County, CA 69 km (43 mi) WSW of here earthquakes near Yolo County
Contra Costa County, CA 75 km (47 mi) NW of here earthquakes near Contra Costa County

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

Aftershocks so far

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

  1. 1.5 12km E of Yountville, CA
  2. 1.7 2km NNW of The Geysers, CA
  3. 2.2 6km ESE of Penngrove, CA
  4. 2.0 3km ENE of The Geysers, CA
  5. 2.2 2km E of The Geysers, CA
  6. 1.6 9km NNE of Benicia, CA
  7. 1.9 2km ESE of The Geysers, CA
  8. 1.5 1km NW of The Geysers, CA
  9. 1.7 5km SSW of Calistoga, CA
  10. 1.7 2km NNE of The Geysers, CA
  11. 2.1 10km NNE of Larkfield-Wikiup, CA
  12. 2.6 4km SSW of Anderson Springs, CA
  13. 2.7 3km NNW of Middletown, CA
  14. 2.0 2km NNE of The Geysers, CA
  15. 1.9 1km 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 4.2 on 2018-01-18 — it released about 4,700 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.