QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

3km NNE of Yorba Linda, CA

· 15 km deep · released about 1,500 lb of TNT

10 km30 km60 km120 km N Orange County 27 kmLos Angeles County 53 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 3.1 (ml)
Depth
15 km below the surface
Felt
426 reports · strongest reported intensity III
Measured shaking
intensity IV (ShakeMap)
Nearest
Orange County, 27 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2465 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 426 people have reported feeling it to USGS.

How big was it?

This earthquake released about 1,500 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 220,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 9,800× the energy of this one
  3. Magna, Utah 2020 M 5.7 6,900× the energy of this one
  4. This earthquake M 3.1 about 1,500 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.6× 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 33.9162, -117.7992. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Orange County, CA 27 km (17 mi) N of here earthquakes near Orange County
Los Angeles County, CA 53 km (33 mi) SE of here earthquakes near Los Angeles County
San Diego County, CA 137 km (85 mi) NW 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

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

  1. 1.7 4km SW of San Bernardino, CA
  2. 1.9 3km WSW of Pedley, CA
  3. 3.4 3km SW of San Bernardino, CA
  4. 1.7 4km SE of Home Gardens, CA
  5. 2.3 3km N of Colton, CA
  6. 1.5 2km WNW of Willowbrook, CA
  7. 1.7 4km SE of Home Gardens, CA
  8. 1.8 8km ESE of Yorba Linda, CA
  9. 2.2 8km ESE of Yorba Linda, CA
  10. 3.6 8km ESE of Yorba Linda, CA
  11. 2.2 7km SSW of Lytle Creek, CA
  12. 1.6 7km SSW of Lytle Creek, CA
  13. 1.8 3km NNW of Orange, CA
  14. 1.5 4km SW of Fontana, CA
  15. 1.8 4km SW of Fontana, 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 72 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.