QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5md

12km N of Brooktrails, CA

· 8.1 km deep · released about 5.4 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mendocino County 14 kmLake County 74 kmGlenn County 84 kmColusa County 107 kmTehama County 117 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 1.5 (md)
Depth
8.1 km below the surface
Felt
no reports yet
Nearest
Mendocino County, 14 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1993 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 5.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,800,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 2,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 180× the energy of this one
  4. This earthquake M 1.5 about 5.4 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 39.5517, -123.3843. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 14 km (9 mi) NNE of here earthquakes near Mendocino County
Lake County, CA 74 km (46 mi) NW of here earthquakes near Lake County
Glenn County, CA 84 km (52 mi) W of here earthquakes near Glenn County
Colusa County, CA 107 km (66 mi) WNW of here earthquakes near Colusa County
Tehama County, CA 117 km (73 mi) WSW of here earthquakes near Tehama County
Sonoma County, CA 121 km (75 mi) NNW of here earthquakes near Sonoma 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. 2.5 7km ESE of Willits, CA
  2. 1.8 4km NNE of Lake Pillsbury, CA
  3. 1.9 4km NNW of Laytonville, CA
  4. 2.2 12km E of Navarro Head, CA
  5. 1.8 10km SE of Willits, CA
  6. 1.6 8km ENE of Willits, CA
  7. 1.8 6km N of Lake Pillsbury, CA
  8. 2.0 11km W of Alder Springs, CA
  9. 1.5 10km SE of Willits, CA
  10. 1.9 10km SE of Willits, CA
  11. 1.9 5km SSE of Redwood Valley, CA
  12. 1.9 6km SSE of Redwood Valley, CA
  13. 1.5 16km E of Navarro Head, CA
  14. 1.9 8km NNW of Redwood Valley, CA
  15. 2.0 12km WNW of Lake Pillsbury, 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 4.3 on 2019-04-29 — it released about 17,000 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.