QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

8km N of Rancho Cucamonga, CA

· 11 km deep · released about 13 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 60 kmLos Angeles County 62 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 1.8 (ml)
Depth
11 km below the surface
Felt
no reports yet
Nearest
Orange County, 60 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3421 days ago

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

How big was it?

This earthquake released about 13 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 840,000× the energy of this one
  3. Around the size people start to feel M 3.0 75× the energy of this one
  4. This earthquake M 1.8 about 13 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 34.1968, -117.5898. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Orange County, CA 60 km (38 mi) NNE of here earthquakes near Orange County
Los Angeles County, CA 62 km (38 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 6km E of Running Springs, CA
  2. 2.2 8km N of Rancho Cucamonga, CA
  3. 1.5 6km E of Running Springs, CA
  4. 1.5 5km SE of Home Gardens, CA
  5. 2.8 2km SE of Loma Linda, CA
  6. 1.6 2km ESE of Loma Linda, CA
  7. 1.8 5km SSE of Lytle Creek, CA
  8. 1.6 1 km ESE of Loma Linda, California
  9. 1.5 6 km SSE of Lytle Creek, California
  10. 2.0 8 km ENE of San Antonio Heights, California
  11. 1.6 3 km ENE of El Cerrito Corona, California
  12. 1.7 3 km NNE of Fontana, California
  13. 2.0 5 km NW of Fontana, California
  14. 1.7 5 km E of Running Springs, California
  15. 1.6 4 km SSE of Placentia, California

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.