QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

15km E of Viola, CA

· -1.1 km deep · released about 13 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Shasta County 54 kmTehama County 74 kmLassen County 78 kmPlumas County 80 kmButte County 93 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
-1.1 km below the surface
Felt
no reports yet
Nearest
Shasta County, 54 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2872 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 13 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 1,200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 840,000× the energy of this one
  3. Around the size people start to feel M 3.0 75× the energy of this one
  4. This earthquake M 1.8 about 13 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 40.4958, -121.5015. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Shasta County, CA 54 km (34 mi) ESE of here earthquakes near Shasta County
Tehama County, CA 74 km (46 mi) NE of here earthquakes near Tehama County
Lassen County, CA 78 km (49 mi) WSW of here earthquakes near Lassen County
Plumas County, CA 80 km (50 mi) NW of here earthquakes near Plumas County
Butte County, CA 93 km (58 mi) N of here earthquakes near Butte County
Glenn County, CA 125 km (78 mi) NE of here earthquakes near Glenn 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. 1.8 22km SE of Burney, CA
  2. 1.8 24km SE of Burney, CA
  3. 1.6 22km SE of Burney, CA
  4. 1.9 22km SE of Burney, CA
  5. 1.9 9km SSE of Mineral, CA
  6. 2.4 22km SE of Burney, CA
  7. 1.6 22km SE of Burney, CA
  8. 1.7 21km SE of Burney, CA
  9. 1.6 22km SE of Burney, CA
  10. 3.0 21km SE of Burney, CA
  11. 2.4 21km SE of Burney, CA
  12. 1.9 22km SE of Burney, CA
  13. 1.8 18km NW of Viola, CA
  14. 1.6 18km NW of Viola, 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.