QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9ml

3 km S of Mentone, CA

· 8.1 km deep · released about 650 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 73 kmLos Angeles County 106 kmRiverside County 110 kmSan Diego County 118 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 2.9 (ml)
Depth
8.1 km below the surface
Felt
94 reports · strongest reported intensity III
Measured shaking
intensity III (ShakeMap)
Nearest
Orange County, 73 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 547 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 94 people have reported feeling it to USGS.

How big was it?

This earthquake released about 650 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 23,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 16,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.5× the energy of this one
  4. This earthquake M 2.9 about 650 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 34.0458, -117.1297. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Orange County, CA 73 km (45 mi) NE of here earthquakes near Orange County
Los Angeles County, CA 106 km (66 mi) E of here earthquakes near Los Angeles County
Riverside County, CA 110 km (68 mi) WNW of here earthquakes near Riverside County
San Diego County, CA 118 km (74 mi) NNW of here earthquakes near San Diego County
San Bernardino County, CA 125 km (78 mi) SW of here earthquakes near San Bernardino County

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

Aftershocks so far

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

  1. 1.6 6 km N of Moreno Valley, CA
  2. 1.8 7 km NNW of Banning, CA
  3. 1.8 3 km NNE of Home Gardens, CA
  4. 1.9 0 km SW of Loma Linda, CA
  5. 1.7 6 km SSE of Lytle Creek, CA
  6. 1.5 6 km WNW of Fontana, CA
  7. 3.3 18 km N of Cabazon, CA
  8. 1.7 8 km SE of Valle Vista, CA
  9. 1.9 10 km NNW of Idyllwild, CA
  10. 1.6 5 km NNW of Big Bear Lake, CA
  11. 1.6 8 km NNE of Banning, CA
  12. 2.0 6 km SE of Ontario, CA
  13. 1.6 4 km SE of Home Gardens, CA
  14. 2.6 5 km NNE of San Bernardino, CA
  15. 1.8 15 km N of Cabazon, 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 250 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.