QuakeIndex

quarry blast · reviewed by a seismologist

M 1.5ml

4km SE of Home Gardens, CA

· 0.5 km deep · released about 5.7 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 32 kmLos Angeles County 80 kmSan Diego County 114 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 1.5 (ml)
Depth
0.5 km below the surface
Felt
no reports yet
Nearest
Orange County, 32 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3768 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

USGS catalogues this as quarry blast, not an earthquake.

How big was it?

This earthquake released about 5.7 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 2,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,900,000× the energy of this one
  3. Around the size people start to feel M 3.0 170× the energy of this one
  4. This earthquake M 1.5 about 5.7 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 33.8500, -117.4982. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Orange County, CA 32 km (20 mi) NE of here earthquakes near Orange County
Los Angeles County, CA 80 km (50 mi) ESE of here earthquakes near Los Angeles County
San Diego County, CA 114 km (71 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

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

  1. 2.3 2km NNE of Costa Mesa, CA
  2. 2.1 2km N of Costa Mesa, CA
  3. 1.5 8km SSW of Lytle Creek, CA
  4. 2.1 4km NNW of San Jacinto, CA
  5. 1.8 2km SW of Mira Loma, CA
  6. 2.0 7km SSW of Devore, CA
  7. 1.7 7km SSW of Devore, CA
  8. 1.6 2km SSE of Loma Linda, CA
  9. 2.4 2km NE of Colton, CA
  10. 2.1 8km WNW of San Jacinto, CA
  11. 1.6 4km NNW of Glen Avon, CA
  12. 1.7 1km S of Ontario, CA
  13. 2.9 3km WNW of Yorba Linda, CA
  14. 1.6 2km NE of Placentia, CA
  15. 1.5 2km SW of Mira Loma, 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.