QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

5km E of Lake Pillsbury, CA

· 7.4 km deep · released about 10 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lake County 36 kmMendocino County 46 kmGlenn County 49 kmColusa County 63 kmSonoma County 98 kmTehama County 99 kmSutter County 111 kmNapa County 111 kmButte County 115 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
7.4 km below the surface
Felt
no reports yet
Nearest
Lake County, 36 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1676 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 39.4025, -122.9055. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lake County, CA 36 km (22 mi) NNW of here earthquakes near Lake County
Mendocino County, CA 46 km (29 mi) E of here earthquakes near Mendocino County
Glenn County, CA 49 km (30 mi) WSW of here earthquakes near Glenn County
Colusa County, CA 63 km (39 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 99 km (61 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

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

  1. 1.8 9km SE of Talmage, CA
  2. 1.7 6km ESE of Lake Pillsbury, CA
  3. 1.7 4km E of Willits, CA
  4. 1.8 6km ESE of Lake Pillsbury, CA
  5. 1.6 15km NW of Lake Pillsbury, CA
  6. 1.6 5km ENE of Talmage, CA
  7. 1.6 12km W of Ukiah, CA
  8. 1.8 10km SE of Willits, CA
  9. 1.6 10km SE of Willits, CA
  10. 1.6 18km SE of Lake Pillsbury, CA
  11. 1.7 10km SE of Willits, CA
  12. 1.5 10km SE of Willits, CA
  13. 2.1 18km NE of Upper Lake, CA
  14. 1.6 12km ENE of Upper Lake, CA
  15. 1.7 10km SE of Willits, 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 5.1 on 2016-08-10 — it released about 130,000 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.