QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

18km NW of Viola, CA

· 7.7 km deep · released about 14 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Shasta County 24 kmTehama County 68 kmLassen County 101 kmTrinity County 110 kmButte County 110 kmPlumas County 111 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 1.8 (md)
Depth
7.7 km below the surface
Felt
no reports yet
Nearest
Shasta County, 24 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1472 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 14 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 790,000× the energy of this one
  3. Around the size people start to feel M 3.0 70× the energy of this one
  4. This earthquake M 1.8 about 14 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 40.6422, -121.8115. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Shasta County, CA 24 km (15 mi) SE of here earthquakes near Shasta County
Tehama County, CA 68 km (42 mi) NNE of here earthquakes near Tehama County
Lassen County, CA 101 km (63 mi) W of here earthquakes near Lassen County
Trinity County, CA 110 km (68 mi) E of here earthquakes near Trinity County
Butte County, CA 110 km (68 mi) N of here earthquakes near Butte County
Plumas County, CA 111 km (69 mi) NW of here earthquakes near Plumas 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. 2.0 12km SSW of Manton, CA
  2. 2.2 12km NNE of Bella Vista, CA
  3. 2.1 8km ENE of Montgomery Creek, CA
  4. 2.3 21km SSE of Burney, CA
  5. 1.9 8km ENE of Shasta Lake, CA
  6. 1.8 13km NNE of Bella Vista, CA
  7. 2.1 12km NNE of Bella Vista, CA
  8. 2.0 1km SE of Palo Cedro, CA
  9. 2.5 5km SW of Palo Cedro, CA
  10. 1.7 4km ESE of Redding, CA
  11. 1.7 6km W of Bella Vista, CA
  12. 1.9 12km S of Manton, CA
  13. 2.4 17km SE of Anderson, CA
  14. 1.8 4km SE of Redding, CA
  15. 1.8 18km NW of Viola, 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.