QuakeIndex

Earthquake · reviewed by a seismologist

M 4.2mw

1 km W of Lytle Creek, CA

· 9.1 km deep · released about 25 tons of TNT

10 km30 km60 km120 km N Orange County 69 kmLos Angeles County 70 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 4.2 (mw)
Depth
9.1 km below the surface
Felt
12827 reports · strongest reported intensity V
Measured shaking
intensity V (ShakeMap)
USGS impact alert
green
Nearest
Orange County, 69 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 280 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 12827 people have reported feeling it to USGS.

How big was it?

This earthquake released about 25 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 6,700× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 300× the energy of this one
  3. Magna, Utah 2020 M 5.7 210× the energy of this one
  4. This earthquake M 4.2 about 25 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 53× more

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 34.2583, -117.5088. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Orange County, CA 69 km (43 mi) NNE of here earthquakes near Orange County
Los Angeles County, CA 70 km (43 mi) E of here earthquakes near Los Angeles County

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

Aftershocks so far

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

  1. 3.1 3 km SW of San Bernardino, CA
  2. 1.5 2 km SE of Loma Linda, CA
  3. 1.6 5 km ESE of Yorba Linda, CA
  4. 1.6 4 km SE of Home Gardens, CA
  5. 2.3 8 km SSE of Wrightwood, CA
  6. 1.5 6 km SSW of Devore, CA
  7. 1.6 1 km S of Colton, CA
  8. 1.5 9 km W of Calimesa, CA
  9. 1.9 9 km W of Calimesa, CA
  10. 1.6 6 km N of Moreno Valley, CA
  11. 1.6 5 km SSE of Home Gardens, CA
  12. 2.4 2 km SSE of Loma Linda, CA
  13. 1.5 4 km SE of Loma Linda, CA
  14. 1.5 6 km S of Lytle Creek, CA
  15. 2.0 6 km ENE of Running Springs, 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 2.2 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.