QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8md

1km WNW of Twain, CA

· 8.4 km deep · released about 550 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Plumas County 20 kmButte County 61 kmSierra County 67 kmNevada County 84 kmLassen County 86 kmYuba County 87 kmTehama County 100 kmPlacer County 111 kmShasta County 117 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 2.8 (md)
Depth
8.4 km below the surface
Felt
2 reports · strongest reported intensity II
Nearest
Plumas County, 20 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2535 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 2 people have reported feeling it to USGS.

How big was it?

This earthquake released about 550 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 28,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 19,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.7× the energy of this one
  4. This earthquake M 2.8 about 550 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 40.0215, -121.0598. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Plumas County, CA 20 km (13 mi) W of here earthquakes near Plumas County
Butte County, CA 61 km (38 mi) NE of here earthquakes near Butte County
Sierra County, CA 67 km (42 mi) NW of here earthquakes near Sierra County
Nevada County, CA 84 km (52 mi) NNW of here earthquakes near Nevada County
Lassen County, CA 86 km (53 mi) SSW of here earthquakes near Lassen County
Yuba County, CA 87 km (54 mi) NNE of here earthquakes near Yuba County

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

Aftershocks so far

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

  1. 1.8 7km N of Greenhorn, CA
  2. 1.6 7km NNW of Greenville, CA
  3. 1.5 8km NE of East Shore, CA
  4. 1.5 8km ENE of Hamilton Branch, CA
  5. 1.5 2km W of Almanor, CA
  6. 1.5 6 km ENE of East Quincy, California
  7. 1.6 3km NE of Canyondam, CA
  8. 2.1 6km NNW of Greenville, CA
  9. 2.0 3km NNE of Spring Garden, CA
  10. 3.1 2km NE of Prattville, CA
  11. 1.6 9 km NNW of Greenhorn, California
  12. 1.8 7km SW of Susanville, CA
  13. 1.6 4km NNE of Belden, CA
  14. 1.5 15km ENE of East Shore, CA
  15. 1.7 5km NE of Canyondam, 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.