QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5ml

5km WSW of Norco, CA

· 13 km deep · released about 160 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 31 kmLos Angeles County 68 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 2.5 (ml)
Depth
13 km below the surface
Felt
5 reports · strongest reported intensity III
Nearest
Orange County, 31 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3702 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 5 people have reported feeling it to USGS.

How big was it?

This earthquake released about 160 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 95,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 68,000× the energy of this one
  3. Around the size people start to feel M 3.0 6× the energy of this one
  4. This earthquake M 2.5 about 160 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 33.9173, -117.6040. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Orange County, CA 31 km (19 mi) NNE of here earthquakes near Orange County
Los Angeles County, CA 68 km (42 mi) ESE of here earthquakes near Los Angeles County
San Diego County, CA 126 km (78 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

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

  1. 1.5 7km SSE of Home Gardens, CA
  2. 2.0 2km ESE of Rowland Heights, CA
  3. 2.1 4km W of Costa Mesa, CA
  4. 2.9 1km E of Loma Linda, CA
  5. 1.5 3km SE of Brea, CA
  6. 2.4 1km SSE of Loma Linda, CA
  7. 2.0 2km E of Loma Linda, CA
  8. 1.6 4km SE of Home Gardens, CA
  9. 1.6 7km SSE of Home Gardens, CA
  10. 1.6 5km SE of Home Gardens, CA
  11. 2.4 4km N of Loma Linda, CA
  12. 1.6 2km N of Bradbury, CA
  13. 1.9 1km ENE of Brea, CA
  14. 1.9 3km NNW of Baldwin Park, CA
  15. 2.3 2km SSE of Mentone, 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.