QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

5km SW of Big Bend, CA

· 12 km deep · released about 16 lb of TNT

10 km30 km60 km120 km N Shasta County 26 kmSiskiyou County 83 kmTehama County 98 kmTrinity County 105 kmLassen County 115 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
12 km below the surface
Felt
no reports yet
Nearest
Shasta County, 26 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2686 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 16 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 5.8 930,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 660,000× the energy of this one
  3. Around the size people start to feel M 3.0 59× the energy of this one
  4. This earthquake M 1.8 about 16 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 40.9840, -121.9458. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Shasta County, CA 26 km (16 mi) NNE of here earthquakes near Shasta County
Siskiyou County, CA 83 km (52 mi) SE of here earthquakes near Siskiyou County
Tehama County, CA 98 km (61 mi) NNE of here earthquakes near Tehama County
Trinity County, CA 105 km (65 mi) ENE of here earthquakes near Trinity County
Lassen County, CA 115 km (72 mi) WNW of here earthquakes near Lassen County
Modoc County, CA 123 km (76 mi) WSW of here earthquakes near Modoc County

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

Aftershocks so far

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

  1. 1.8 13km N of McCloud, CA
  2. 1.5 13km N of McCloud, CA
  3. 1.5 14km N of McCloud, CA
  4. 1.6 13km N of McCloud, CA
  5. 1.5 13km N of McCloud, CA
  6. 2.0 13km N of McCloud, CA
  7. 1.8 13km N of McCloud, CA
  8. 1.8 13km N of McCloud, CA
  9. 2.3 13km N of McCloud, CA
  10. 1.9 14km N of McCloud, CA
  11. 1.8 14km N of McCloud, CA
  12. 2.3 14km N of McCloud, CA
  13. 2.3 13km N of McCloud, CA
  14. 1.5 14km N of McCloud, CA
  15. 1.6 17km NNW 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.