QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1ml

9km NNE of Big Bear City, CA

· 3.5 km deep · released about 41 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Bernardino County 82 kmRiverside County 101 kmOrange 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 2.1 (ml)
Depth
3.5 km below the surface
Felt
no reports yet
Nearest
San Bernardino County, 82 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1505 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 41 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 370,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 260,000× the energy of this one
  3. Around the size people start to feel M 3.0 23× the energy of this one
  4. This earthquake M 2.1 about 41 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 34.3408, -116.8185. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
San Bernardino County, CA 82 km (51 mi) SW of here earthquakes near San Bernardino County
Riverside County, CA 101 km (63 mi) NW of here earthquakes near Riverside County
Orange County, CA 115 km (72 mi) NE of here earthquakes near Orange County

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

Aftershocks so far

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

  1. 1.8 2km NW of Cabazon, CA
  2. 1.7 39km WSW of Ludlow, CA
  3. 1.6 9km N of Cabazon, CA
  4. 1.9 9km NNW of Big Bear City, CA
  5. 2.0 6km S of Big Bear City, CA
  6. 1.8 7km ESE of Yucaipa, CA
  7. 2.1 3km WNW of Beaumont, CA
  8. 1.6 10km NNW of Big Bear City, CA
  9. 1.9 4km SSW of Calimesa, CA
  10. 3.0 4km W of Banning, CA
  11. 2.1 8km NE of Cabazon, CA
  12. 1.9 11km SE of Lucerne Valley, CA
  13. 1.6 8km SSE of Big Bear City, CA
  14. 2.5 9km ENE of Yucaipa, CA
  15. 2.3 39km WSW of Ludlow, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.5 on 2018-05-08 — it released about 4,000 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.