QuakeIndex

Earthquake · reviewed by a seismologist

M 3.6mw

7km S of Lytle Creek, CA

· 5.0 km deep · released about 4.1 tons of TNT

10 km30 km60 km120 km N Orange County 63 kmLos Angeles County 69 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 3.6 (mw)
Depth
5.0 km below the surface
Felt
994 reports · strongest reported intensity IV
Measured shaking
intensity IV (ShakeMap)
Nearest
Orange County, 63 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 977 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 994 people have reported feeling it to USGS.

How big was it?

This earthquake released about 4.1 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.6 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 42,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 1,900× the energy of this one
  3. Magna, Utah 2020 M 5.7 1,300× the energy of this one
  4. This earthquake M 3.6 about 4.1 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 8.5× 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 34.2005, -117.5068. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Orange County, CA 63 km (39 mi) NNE of here earthquakes near Orange County
Los Angeles County, CA 69 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

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

  1. 1.5 2km NW of Loma Linda, CA
  2. 1.8 3km SSW of San Bernardino, CA
  3. 1.6 10km NE of Lake Arrowhead, CA
  4. 1.5 3km ESE of Loma Linda, CA
  5. 2.0 7km NE of Lake Arrowhead, CA
  6. 1.7 10km WNW of Big Bear Lake, CA
  7. 1.7 10km WNW of Big Bear Lake, CA
  8. 1.8 8km N of Glendora, CA
  9. 2.6 2km S of Redlands, CA
  10. 1.5 4km SSW of Redlands, CA
  11. 1.6 2km NNW of Fontana, CA
  12. 1.5 2km E of Home Gardens, CA
  13. 1.5 4km SE of Home Gardens, CA
  14. 1.7 6km WNW of Fontana, CA
  15. 1.6 3km E of Yucaipa, 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 14 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.