QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

25 km NW of Alder Springs, CA

· 8.0 km deep · released about 8.7 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Glenn County 52 kmMendocino County 59 kmTehama County 71 kmLake County 79 kmColusa County 92 kmTrinity County 96 kmButte County 116 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 1.6 (md)
Depth
8.0 km below the surface
Felt
no reports yet
Nearest
Glenn County, 52 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1067 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 8.7 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,700,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,200,000× the energy of this one
  3. Around the size people start to feel M 3.0 110× the energy of this one
  4. This earthquake M 1.6 about 8.7 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 39.7972, -122.9502. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Glenn County, CA 52 km (32 mi) WNW of here earthquakes near Glenn County
Mendocino County, CA 59 km (36 mi) NE of here earthquakes near Mendocino County
Tehama County, CA 71 km (44 mi) WSW of here earthquakes near Tehama County
Lake County, CA 79 km (49 mi) NNW of here earthquakes near Lake County
Colusa County, CA 92 km (57 mi) NW of here earthquakes near Colusa County
Trinity County, CA 96 km (59 mi) S of here earthquakes near Trinity County

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

Aftershocks so far

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

  1. 2.4 41 km NNE of Covelo, CA
  2. 1.8 10 km WNW of Alder Springs, CA
  3. 1.5 13 km WNW of Lake Pillsbury, CA
  4. 1.7 13 km WNW of Lake Pillsbury, CA
  5. 1.7 2 km SW of Lake Pillsbury, CA
  6. 2.1 17 km NNE of Laytonville, CA
  7. 1.6 10 km SSE of Laytonville, CA
  8. 2.2 7 km NNW of Lake Pillsbury, CA
  9. 1.6 19 km WNW of Lake Pillsbury, CA
  10. 1.8 12 km N of Brooktrails, CA
  11. 1.7 6 km N of Laytonville, CA
  12. 1.7 6 km ESE of Lake Pillsbury, CA
  13. 1.7 5 km ESE of Lake Pillsbury, CA
  14. 1.6 8 km ENE of Brooktrails, CA
  15. 2.6 11 km N of Brooktrails, 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 4.1 on 2021-11-04 — 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.