QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

3km NW of Glen Avon, CA

· 2.8 km deep · released about 17 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 47 kmLos Angeles County 72 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 (ml)
Depth
2.8 km below the surface
Felt
3 reports · strongest reported intensity III
Nearest
Orange County, 47 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2644 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 3 people have reported feeling it to USGS.

How big was it?

This earthquake released about 17 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 5.8 870,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 620,000× the energy of this one
  3. Around the size people start to feel M 3.0 55× the energy of this one
  4. This earthquake M 1.8 about 17 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 34.0352, -117.5087. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Orange County, CA 47 km (29 mi) NNE of here earthquakes near Orange County
Los Angeles County, CA 72 km (45 mi) ESE of here earthquakes near Los Angeles County
San Diego County, CA 131 km (82 mi) NNW of here earthquakes near San Diego 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. 1.9 6km SW of Fontana, CA
  2. 2.6 7km NNW of Fontana, CA
  3. 2.8 5km SE of Loma Linda, CA
  4. 1.6 6km SW of Fontana, CA
  5. 1.7 5km SE of Home Gardens, CA
  6. 1.5 8km ENE of North Tustin, CA
  7. 1.7 3km S of Redlands, CA
  8. 1.9 5km NNW of Glen Avon, CA
  9. 2.1 5km SW of Fontana, CA
  10. 1.6 5km NNW of Glen Avon, CA
  11. 1.6 5km SW of Fontana, CA
  12. 1.6 5km SW of Fontana, CA
  13. 1.6 6km SW of Fontana, CA
  14. 2.0 5km SW of Fontana, CA
  15. 1.6 1km SSW of San Dimas, 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 4.4 on 2018-08-29 — it released about 6,500 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.