QuakeIndex

Earthquake · reviewed by a seismologist

M 4.1mw

2km NNE of Prattville, CA

· 6.7 km deep · released about 24 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Plumas County 38 kmLassen County 70 kmButte County 74 kmSierra County 90 kmTehama County 93 kmShasta County 96 kmYuba County 108 kmNevada County 108 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 4.1 (mw)
Depth
6.7 km below the surface
Felt
89 reports · strongest reported intensity IV
Measured shaking
intensity IV (ShakeMap)
USGS impact alert
green
Nearest
Plumas County, 38 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1155 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 89 people have reported feeling it to USGS.

How big was it?

This earthquake released about 24 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 7,200× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 320× the energy of this one
  3. Magna, Utah 2020 M 5.7 230× the energy of this one
  4. This earthquake M 4.1 about 24 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 50× more

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 40.2267, -121.1478. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Plumas County, CA 38 km (24 mi) NW of here earthquakes near Plumas County
Lassen County, CA 70 km (44 mi) SW of here earthquakes near Lassen County
Butte County, CA 74 km (46 mi) NNE of here earthquakes near Butte County
Sierra County, CA 90 km (56 mi) NW of here earthquakes near Sierra County
Tehama County, CA 93 km (58 mi) E of here earthquakes near Tehama County
Shasta County, CA 96 km (60 mi) SE of here earthquakes near Shasta 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. 2.1 4 km NNE of Canyondam, CA
  2. 2.1 0 km E of Almanor, CA
  3. 1.8 4 km NW of Spring Garden, California
  4. 1.6 1 km E of Almanor, CA
  5. 1.7 4 km NNE of Canyondam, CA
  6. 1.8 37 km N of Chester, CA
  7. 1.8 1 km ENE of Almanor, CA
  8. 2.4 4 km WSW of Hamilton Branch, CA
  9. 2.1 10 km SW of Almanor, CA
  10. 2.5 2 km NNE of Canyondam, CA
  11. 1.9 4 km NW of Almanor, CA
  12. 2.9 1 km ESE of Almanor, CA
  13. 2.2 1 km N of Almanor, CA
  14. 2.1 1 km NNE of Almanor, CA
  15. 1.9 1 km N of Prattville, 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 5.5 on 2023-05-11 — it released about 110 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.