QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

13km WSW of Chester, CA

· 4.4 km deep · released about 49 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Plumas County 56 kmButte County 70 kmTehama County 75 kmShasta County 79 kmLassen County 80 kmSierra County 106 kmYuba County 111 kmGlenn County 115 kmNevada 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 2.1 (md)
Depth
4.4 km below the surface
Felt
no reports yet
Nearest
Plumas County, 56 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2743 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 49 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 5.8 310,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 220,000× the energy of this one
  3. Around the size people start to feel M 3.0 19× the energy of this one
  4. This earthquake M 2.1 about 49 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 40.2710, -121.3727. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Plumas County, CA 56 km (35 mi) NW of here earthquakes near Plumas County
Butte County, CA 70 km (44 mi) NNE of here earthquakes near Butte County
Tehama County, CA 75 km (46 mi) ENE of here earthquakes near Tehama County
Shasta County, CA 79 km (49 mi) SE of here earthquakes near Shasta County
Lassen County, CA 80 km (50 mi) SW of here earthquakes near Lassen County
Sierra County, CA 106 km (66 mi) NW of here earthquakes near Sierra County

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

Aftershocks so far

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

  1. 2.0 2km W of Almanor, CA
  2. 2.1 3km WSW of Almanor, CA
  3. 1.5 3km ESE of Canyondam, CA
  4. 2.0 3km W of Hamilton Branch, CA
  5. 1.9 4km NNW of Almanor, CA
  6. 2.4 2km ESE of Prattville, CA
  7. 1.7 15km NNW of Chester, CA
  8. 1.8 4km SSE of East Shore, CA
  9. 1.6 22km NW of Storrie, CA
  10. 2.0 11km W of Chester, CA
  11. 2.5 11km W of Chester, CA
  12. 1.9 12km SW of Almanor, CA
  13. 1.8 23km S of Mineral, CA
  14. 1.6 18km SSW of Mineral, CA
  15. 2.1 15km WSW of Chester, 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.