QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

10km NNE of Larkfield-Wikiup, CA

· 4.9 km deep · released about 18 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Sonoma County 20 kmNapa County 35 kmLake County 57 kmMarin County 61 kmYolo County 71 kmColusa County 76 kmSolano County 76 kmSutter County 100 kmContra Costa County 100 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
4.9 km below the surface
Felt
no reports yet
Nearest
Sonoma County, 20 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1537 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 18 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 5.8 840,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 600,000× the energy of this one
  3. Around the size people start to feel M 3.0 53× the energy of this one
  4. This earthquake M 1.9 about 18 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 38.5972, -122.7098. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Sonoma County, CA 20 km (13 mi) ENE of here earthquakes near Sonoma County
Napa County, CA 35 km (22 mi) WNW of here earthquakes near Napa County
Lake County, CA 57 km (35 mi) S of here earthquakes near Lake County
Marin County, CA 61 km (38 mi) N of here earthquakes near Marin County
Yolo County, CA 71 km (44 mi) W of here earthquakes near Yolo County
Colusa County, CA 76 km (47 mi) SSW of here earthquakes near Colusa 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. 1.7 9km WNW of Cobb, CA
  2. 1.7 8km NW of The Geysers, CA
  3. 1.8 8km NW of The Geysers, CA
  4. 1.7 8km NW of The Geysers, CA
  5. 1.6 4km ESE of Lower Lake, CA
  6. 1.7 3km SE of The Geysers, CA
  7. 2.3 9km NW of The Geysers, CA
  8. 1.6 7km NW of The Geysers, CA
  9. 1.6 6km WNW of Cobb, CA
  10. 1.9 4km N of Clearlake, CA
  11. 1.7 3km SE of The Geysers, CA
  12. 1.5 4km NNW of The Geysers, CA
  13. 2.2 11km W of The Geysers, CA
  14. 1.6 3km SSW of Anderson Springs, CA
  15. 1.7 3km SSW of Anderson Springs, 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 55,000 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.