QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

17km S of Talmage, CA

· -0.6 km deep · released about 44 lb of TNT

10 km30 km60 km120 km N Lake County 36 kmSonoma County 54 kmMendocino County 57 kmColusa County 80 kmNapa County 87 kmGlenn County 94 kmMarin County 108 kmYolo County 112 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 2.1 (md)
Depth
-0.6 km below the surface
Felt
4 reports · strongest reported intensity IV
Nearest
Lake County, 36 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2216 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 4 people have reported feeling it to USGS.

How big was it?

This earthquake released about 44 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 340,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 240,000× the energy of this one
  3. Around the size people start to feel M 3.0 22× the energy of this one
  4. This earthquake M 2.1 about 44 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 38.9788, -123.1330. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lake County, CA 36 km (23 mi) WSW of here earthquakes near Lake County
Sonoma County, CA 54 km (33 mi) NNW of here earthquakes near Sonoma County
Mendocino County, CA 57 km (35 mi) SSE of here earthquakes near Mendocino County
Colusa County, CA 80 km (50 mi) WSW of here earthquakes near Colusa County
Napa County, CA 87 km (54 mi) NW of here earthquakes near Napa County
Glenn County, CA 94 km (58 mi) SW of here earthquakes near Glenn County

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

Aftershocks so far

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

  1. 1.5 10km ESE of Willits, CA
  2. 2.2 3km NW of Anderson Springs, CA
  3. 1.5 7km NW of The Geysers, CA
  4. 3.0 21km NNW of Boonville, CA
  5. 1.5 2km W of Cobb, CA
  6. 1.7 4km NW of The Geysers, CA
  7. 1.8 7km NW of The Geysers, CA
  8. 1.5 5km S of Lake Pillsbury, CA
  9. 1.8 2km NW of The Geysers, CA
  10. 1.7 8km NW of The Geysers, CA
  11. 1.9 10km ESE of Willits, CA
  12. 1.6 11km ESE of Willits, CA
  13. 1.6 11km ESE of Willits, CA
  14. 1.6 10km ESE of Willits, CA
  15. 2.6 11km ESE 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 30,000 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.