QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

11km ENE of Hidden Valley Lake, CA

· 10 km deep · released about 20 lb of TNT

10 km30 km60 km120 km N Napa County 39 kmLake County 39 kmColusa County 41 kmYolo County 50 kmSonoma County 55 kmSutter County 67 kmSolano County 78 kmGlenn County 84 kmMarin County 92 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 1.9 (md)
Depth
10 km below the surface
Felt
no reports yet
Nearest
Napa County, 39 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1331 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 20 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 760,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 540,000× the energy of this one
  3. Around the size people start to feel M 3.0 48× the energy of this one
  4. This earthquake M 1.9 about 20 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 38.8438, -122.4442. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Napa County, CA 39 km (24 mi) NNW of here earthquakes near Napa County
Lake County, CA 39 km (24 mi) SE of here earthquakes near Lake County
Colusa County, CA 41 km (26 mi) SSW of here earthquakes near Colusa County
Yolo County, CA 50 km (31 mi) WNW of here earthquakes near Yolo County
Sonoma County, CA 55 km (34 mi) NE of here earthquakes near Sonoma County
Sutter County, CA 67 km (42 mi) WSW of here earthquakes near Sutter County

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

Aftershocks so far

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

  1. 1.9 2km NW of The Geysers, CA
  2. 2.5 2km NW of The Geysers, CA
  3. 1.5 7km NW of The Geysers, CA
  4. 2.1 10km WNW of The Geysers, CA
  5. 1.7 6km NW of The Geysers, CA
  6. 1.5 4km NNW of The Geysers, CA
  7. 2.0 2km NW of The Geysers, CA
  8. 2.6 8km WNW of Cobb, CA
  9. 1.8 2km WNW of The Geysers, CA
  10. 2.5 8km NW of The Geysers, CA
  11. 1.9 7km NW of The Geysers, CA
  12. 1.7 2km N of The Geysers, CA
  13. 1.6 6km NW of The Geysers, CA
  14. 1.6 8km N of Cobb, CA
  15. 1.6 9km W of Cobb, 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 50,000 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.