QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

17 km ENE of Potter Valley, California

· 7.1 km deep · released about 14 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lake County 37 kmMendocino County 43 kmGlenn County 52 kmColusa County 66 kmSonoma County 98 kmTehama County 101 kmNapa County 113 kmSutter County 115 kmButte County 119 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
7.1 km below the surface
Felt
no reports yet
Nearest
Lake County, 37 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3386 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 39.4058, -122.9475. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lake County, CA 37 km (23 mi) NNW of here earthquakes near Lake County
Mendocino County, CA 43 km (27 mi) E of here earthquakes near Mendocino County
Glenn County, CA 52 km (32 mi) WSW of here earthquakes near Glenn County
Colusa County, CA 66 km (41 mi) WNW of here earthquakes near Colusa County
Sonoma County, CA 98 km (61 mi) N of here earthquakes near Sonoma County
Tehama County, CA 101 km (63 mi) SW of here earthquakes near Tehama County

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

Aftershocks so far

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

  1. 1.8 17 km NE of Upper Lake, California
  2. 1.5 19 km NNE of Upper Lake, California
  3. 1.5 9 km NE of Willits, California
  4. 1.5 15 km NE of Potter Valley, California
  5. 1.7 15 km NE of Potter Valley, California
  6. 1.9 15 km NE of Potter Valley, California
  7. 1.9 17 km NW of Elk Creek, California
  8. 1.6 8 km E of Willits, California
  9. 2.0 6 km ENE of Calpella, California
  10. 1.7 9 km ESE of Willits, California
  11. 1.6 19 km ENE of Potter Valley, California
  12. 1.7 20 km ENE of Potter Valley, California
  13. 1.5 18 km NE of Upper Lake, California
  14. 1.7 1 km N of Talmage, California
  15. 2.2 19 km NE of Upper Lake, 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 5.1 on 2016-08-10 — 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.