QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

3km NE of San Dimas, CA

· 5.5 km deep · released about 5.9 lb of TNT

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10 km30 km60 km120 km N Los Angeles County 45 kmOrange County 50 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
5.5 km below the surface
Felt
no reports yet
Nearest
Los Angeles County, 45 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2896 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 5.9 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 2,500,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,800,000× the energy of this one
  3. Around the size people start to feel M 3.0 160× the energy of this one
  4. This earthquake M 1.5 about 5.9 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 34.1213, -117.7845. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Los Angeles County, CA 45 km (28 mi) E of here earthquakes near Los Angeles County
Orange County, CA 50 km (31 mi) N of here earthquakes near Orange 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. 1.5 4km WNW of Lytle Creek, CA
  2. 1.9 2km SSE of Loma Linda, CA
  3. 2.1 11km NE of Trabuco Canyon, CA
  4. 1.7 3km SE of Lytle Creek, CA
  5. 1.5 6km SSW of Lytle Creek, CA
  6. 1.5 4km NNW of La Verne, CA
  7. 1.6 6km WSW of Devore, CA
  8. 1.8 4km SE of Home Gardens, CA
  9. 1.6 7km SE of Home Gardens, CA
  10. 1.7 4km N of La Verne, CA
  11. 1.6 7km NW of Rancho Cucamonga, CA
  12. 1.5 4km SE of Home Gardens, CA
  13. 1.9 7km S of Lytle Creek, CA
  14. 1.6 0km SSW of Loma Linda, CA
  15. 2.1 4km ENE of Lytle Creek, 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 19,000 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.