QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

18km WNW of Round Mountain, CA

· 15 km deep · released about 13 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Shasta County 14 kmTehama County 82 kmTrinity County 85 kmSiskiyou County 88 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
15 km below the surface
Felt
no reports yet
Nearest
Shasta County, 14 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2738 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 40.8565, -122.1422. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Shasta County, CA 14 km (8 mi) NW of here earthquakes near Shasta County
Tehama County, CA 82 km (51 mi) N of here earthquakes near Tehama County
Trinity County, CA 85 km (53 mi) ENE of here earthquakes near Trinity County
Siskiyou County, CA 88 km (54 mi) SSE of here earthquakes near Siskiyou County
Modoc County, CA 145 km (90 mi) SW of here earthquakes near Modoc County
Plumas County, CA 147 km (91 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

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

  1. 1.6 3km SW of Shasta Lake, CA
  2. 1.6 17km NNW of Shingletown, CA
  3. 1.5 9km SE of Dunsmuir, CA
  4. 1.8 5km N of McCloud, CA
  5. 2.0 8km WSW of Dunsmuir, CA
  6. 1.6 14km NNE of French Gulch, CA
  7. 1.7 13km NNE of French Gulch, CA
  8. 1.8 9km NNE of Shasta Lake, CA
  9. 1.8 18km NW of Viola, CA
  10. 1.8 17km NNE of Bella Vista, CA
  11. 1.6 18km NW of Viola, CA
  12. 1.8 18km NW of Viola, CA
  13. 1.6 26km NNE of Shasta Lake, CA
  14. 1.6 18km NW of Viola, CA
  15. 2.2 18km NNE of Shingletown, 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.