QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

4km NNE of Fontana, CA

· 6.9 km deep · released about 6.4 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 59 kmLos Angeles County 76 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 1.6 (ml)
Depth
6.9 km below the surface
Felt
no reports yet
Nearest
Orange County, 59 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3518 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 6.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,400,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,700,000× the energy of this one
  3. Around the size people start to feel M 3.0 150× the energy of this one
  4. This earthquake M 1.6 about 6.4 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 34.1278, -117.4422. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Orange County, CA 59 km (37 mi) NNE of here earthquakes near Orange County
Los Angeles County, CA 76 km (47 mi) E of here earthquakes near Los Angeles County
San Bernardino County, CA 141 km (88 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

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

  1. 1.5 3km NE of Fontana, CA
  2. 1.8 4km SE of Loma Linda, CA
  3. 1.9 11km NE of Running Springs, CA
  4. 1.7 4km SE of Yucaipa, CA
  5. 2.1 6km N of Lytle Creek, CA
  6. 1.5 2km NNE of Colton, CA
  7. 1.6 3km NNE of Colton, CA
  8. 2.3 6km WNW of Lytle Creek, CA
  9. 1.7 10km WNW of Corona, CA
  10. 1.8 2km NNW of San Bernardino, CA
  11. 2.2 1km NNW of Lake Arrowhead, CA
  12. 1.8 6km E of Calimesa, CA
  13. 1.5 10km NNW of Banning, CA
  14. 3.0 5km SE of Lytle Creek, CA
  15. 2.5 6km S of Redlands, 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.