QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

12 km N of Brooktrails, CA

· 8.2 km deep · released about 20 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mendocino County 15 kmLake County 72 kmGlenn County 82 kmColusa County 105 kmTehama 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 1.9 (md)
Depth
8.2 km below the surface
Felt
no reports yet
Nearest
Mendocino County, 15 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1073 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 20 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 760,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 540,000× the energy of this one
  3. Around the size people start to feel M 3.0 48× the energy of this one
  4. This earthquake M 1.9 about 20 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 39.5543, -123.3583. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 15 km (10 mi) NNE of here earthquakes near Mendocino County
Lake County, CA 72 km (45 mi) NW of here earthquakes near Lake County
Glenn County, CA 82 km (51 mi) W of here earthquakes near Glenn County
Colusa County, CA 105 km (65 mi) WNW of here earthquakes near Colusa County
Tehama County, CA 115 km (72 mi) WSW of here earthquakes near Tehama County
Sonoma County, CA 120 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

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

  1. 1.8 16 km ESE of Navarro Head, CA
  2. 1.9 11 km NNW of Lake Pillsbury, CA
  3. 1.8 11 km NNW of Laytonville, CA
  4. 1.8 7 km SE of Lake Pillsbury, CA
  5. 2.1 10 km NNW of Laytonville, CA
  6. 1.8 14 km SSW of Laytonville, CA
  7. 2.1 6 km SSE of Redwood Valley, CA
  8. 1.6 10 km ESE of Willits, CA
  9. 1.6 10 km ESE of Rockport, CA
  10. 1.6 9 km NNE of Rockport, CA
  11. 1.9 14 km WNW of Lake Pillsbury, CA
  12. 1.8 14 km WNW of Lake Pillsbury, CA
  13. 1.5 23 km SSW of Willits, CA
  14. 1.8 10 km NNW of Redwood Valley, CA
  15. 1.6 15 km WNW of Ukiah, 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 4,600 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.