QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

5km WNW of Angwin, CA

· 4.4 km deep · released about 10 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Napa County 18 kmSonoma County 37 kmYolo County 53 kmLake County 61 kmSolano County 61 kmMarin County 64 kmColusa County 69 kmSutter County 85 kmContra Costa County 89 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 1.7 (md)
Depth
4.4 km below the surface
Felt
no reports yet
Nearest
Napa County, 18 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2031 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 10 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,500,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,100,000× the energy of this one
  3. Around the size people start to feel M 3.0 95× the energy of this one
  4. This earthquake M 1.7 about 10 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 38.5927, -122.5080. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Napa County, CA 18 km (11 mi) WNW of here earthquakes near Napa County
Sonoma County, CA 37 km (23 mi) ENE of here earthquakes near Sonoma County
Yolo County, CA 53 km (33 mi) W of here earthquakes near Yolo County
Lake County, CA 61 km (38 mi) SSE of here earthquakes near Lake County
Solano County, CA 61 km (38 mi) NW of here earthquakes near Solano County
Marin County, CA 64 km (40 mi) NNE 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. 1.5 6km NW of The Geysers, CA
  2. 1.6 6km NNE of Windsor, CA
  3. 2.5 6km S of Calistoga, CA
  4. 2.9 4km WNW of The Geysers, CA
  5. 2.4 4km WNW of The Geysers, CA
  6. 1.5 7km NW of The Geysers, CA
  7. 1.8 7km NW of The Geysers, CA
  8. 1.9 9km WNW of The Geysers, CA
  9. 1.6 5km WNW of The Geysers, CA
  10. 2.5 2km SSW of Cobb, CA
  11. 2.3 3km NE of The Geysers, CA
  12. 1.6 10km WNW of Calistoga, CA
  13. 1.7 8km NW of The Geysers, CA
  14. 1.9 8km WNW of Cobb, CA
  15. 1.6 8km 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 99,000 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.