QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

15km N of Alder Springs, CA

· 9.5 km deep · released about 11 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Glenn County 33 kmTehama County 55 kmMendocino County 75 kmLake County 76 kmColusa County 79 kmButte County 95 kmTrinity County 102 kmSutter County 120 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
9.5 km below the surface
Felt
no reports yet
Nearest
Glenn County, 33 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2942 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 11 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 1,400,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 970,000× the energy of this one
  3. Around the size people start to feel M 3.0 86× the energy of this one
  4. This earthquake M 1.7 about 11 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 39.7867, -122.7037. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Glenn County, CA 33 km (20 mi) NW of here earthquakes near Glenn County
Tehama County, CA 55 km (34 mi) SW of here earthquakes near Tehama County
Mendocino County, CA 75 km (46 mi) ENE of here earthquakes near Mendocino County
Lake County, CA 76 km (47 mi) N of here earthquakes near Lake County
Colusa County, CA 79 km (49 mi) NNW of here earthquakes near Colusa County
Butte County, CA 95 km (59 mi) W of here earthquakes near Butte County

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

Aftershocks so far

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

  1. 1.6 21km SE of Covelo, CA
  2. 2.7 21km SE of Covelo, CA
  3. 2.4 21km SE of Covelo, CA
  4. 1.7 6km ESE of Lake Pillsbury, CA
  5. 2.0 11km NE of Alder Springs, CA
  6. 1.6 22km NW of Alder Springs, CA
  7. 2.0 19km W of Rancho Tehama Reserve, CA
  8. 1.8 4km SSE of Lake Pillsbury, CA
  9. 1.6 24km NE of Alder Springs, CA
  10. 1.8 34km ENE of Covelo, CA
  11. 1.8 15km NW of Alder Springs, CA
  12. 2.5 20km NNW of Alder Springs, CA
  13. 1.6 20km NNW of Alder Springs, CA
  14. 2.1 20km NNW of Alder Springs, CA
  15. 1.8 3km NW 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.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.