QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

5 km S of Cobb, California

· 2.2 km deep · released about 10 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Sonoma County 33 kmLake County 37 kmNapa County 45 kmColusa County 61 kmYolo County 71 kmMarin County 80 kmSolano County 88 kmSutter County 92 kmGlenn County 96 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
2.2 km below the surface
Felt
no reports yet
Nearest
Sonoma County, 33 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3414 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 1,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 92× 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 38.7743, -122.7140. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Sonoma County, CA 33 km (21 mi) NNE of here earthquakes near Sonoma County
Lake County, CA 37 km (23 mi) S of here earthquakes near Lake County
Napa County, CA 45 km (28 mi) NW of here earthquakes near Napa County
Colusa County, CA 61 km (38 mi) SW of here earthquakes near Colusa County
Yolo County, CA 71 km (44 mi) W of here earthquakes near Yolo County
Marin County, CA 80 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

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

  1. 1.9 8 km W of Cobb, California
  2. 2.5 7 km S of Calistoga, California
  3. 1.8 6 km WSW of Cobb, California
  4. 1.9 6 km W of Cobb, California
  5. 2.0 3 km WSW of Cobb, California
  6. 1.6 7 km S of Cobb, California
  7. 1.7 6 km SSE of Cobb, California
  8. 1.8 10 km WNW of Cobb, California
  9. 1.9 8 km W of Cobb, California
  10. 1.7 7 km S of Cobb, California
  11. 1.9 8 km W of Cobb, California
  12. 1.7 8 km W of Cobb, California
  13. 1.8 5km WNW of The Geysers, CA
  14. 1.9 Northern California
  15. 1.9 8 km WSW of Cobb, California

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 95,000 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.